Category Archive Neurology

Bacterial Meningitis/Meningitis is inflammation of the meninges covering the brain. It is a pathological definition. The cerebrospinal fluid (CSF) typically exhibits an elevated number of leucocytes (or a pleocytosis). In adults, >5 leucocytes/μL is defined as elevated. Bacterial or viral meningitis is confirmed by the detection of a pathogen in the CSF. Bacterial meningitis may also be suggested by symptoms of meningism and appropriate bacteria in the blood.[rx]

Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

Types of Meningitis

Bacterial

Meningitis caused by bacteria can be deadly and requires immediate medical attention. Vaccines are available to help protect against some kinds of bacterial meningitis. Streptococcus pneumoniae- A causative bacteria of meningitis.

The types of bacteria that cause bacterial meningitis vary according to the infected individual’s age group.

• In premature babies and newborns up to three months old – common causes are group B streptococci (subtypes III which normally inhabit the vagina and are mainly a cause during the first week of life) and bacteria that normally inhabit the digestive tract such as Escherichia coli (carrying the K1 antigen). Listeria monocytogenes (serotype IVb) is transmitted by the mother before birth and may cause meningitis in the newborn.
• Older children are more commonly affected by – Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (serotypes 6, 9, 14, 18 and 23) and those under five by Haemophilus influenzae type B (in countries that do not offer vaccination).
• In adults –  Neisseria meningitidis and Streptococcus pneumoniae together cause 80% of bacterial meningitis cases. Risk of infection with Listeria monocytogenes is increased in persons over 50 years old. The introduction of the pneumococcal vaccine has lowered rates of pneumococcal meningitis in both children and adults.
• Recent skull trauma potentially – allows nasal cavity bacteria to enter the meningeal space. Similarly, devices in the brain and meninges, such as cerebral shunts, extraventricular drains or Ommaya reservoirs, carry an increased risk of meningitis. In these cases, the persons are more likely to be infected with Staphylococci, Pseudomonas, and other Gram-negative bacteria. These pathogens are also associated with meningitis in people with an impaired immune system.
• Tuberculous meningitis – which is meningitis caused by Mycobacterium tuberculosis, is more common in people from countries in which tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS.

Viral

• Meningitis caused by viruses is serious but often is less severe than bacterial meningitis. People with normal immune systems who get viral meningitis usually get better on their own. There are vaccines to prevent some kinds of viral meningitis.
• Viruses that cause meningitis include enteroviruses, herpes simplex virus (generally type 2, which produces most genital sores; less commonly type 1), varicella zoster virus (known for causing chickenpox and shingles), mumps virus, HIV, and LCMV. Mollaret’s meningitis is a chronic recurrent form of herpes meningitis; it is thought to be caused by herpes simplex virus type 2.

Fungal

• Meningitis caused by fungi is rare, but people can get it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
• There are a number of risk factors for fungal meningitis, including the use of immunosuppressants (such as after organ transplantation), HIV/AIDS, and the loss of immunity associated with aging. It is uncommon in those with a normal immune system but has occurred with medication contamination.
• Symptom onset is typically more gradual, with headaches and fever being present for at least a couple of weeks before diagnosis. The most common fungal meningitis is cryptococcal meningitis due to Cryptococcus neoformans.
• In Africa, cryptococcal meningitis is now the most common cause of meningitis in multiple studies, and it accounts for 20–25% of AIDS-related deaths in Africa. Other less common fungal pathogens which can cause meningitis include: Coccidioides immitis, Histoplasma capsulatum, Blastomyces dermatitidis, and Candidaspecies.

Parasitic

• Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Overall, parasitic meningitis is much less common than viral and bacterial meningitis.
• A parasitic cause is often assumed when there is a predominance of eosinophils (a type of white blood cell) in the CSF. The most common parasites implicated are Angiostrongylus cantonensis, Gnathostoma spinigerum, Schistosoma, as well as the conditions cysticercosis, toxocariasis, baylisascariasis, paragonimiasis, and a number of rarer infections and noninfective conditions.

Aseptic meningitis

Aseptic meningitis is a term referring to the broad category of meningitis that is not caused by bacteria. Approximately 50% of aseptic meningitis is due to viral infections. Other less common causes include

• drug reactions or allergies, and
• inflammatory diseases like lupus.

Non-infectious

• Meningitis may occur as the result of several non-infectious causes: the spread of cancer to the meninges (malignant or neoplastic meningitis) and certain drugs (mainly non-steroidal anti-inflammatory drugs, antibiotics and intravenous immunoglobulins).
• It may also be caused by several inflammatory conditions, such as sarcoidosis (which is then called neurosarcoidosis), connective tissue disorders such as systemic lupus erythematosus, and certain forms of vasculitis (inflammatory conditions of the blood vessel wall), such as Behçet’s disease. Epidermoid cysts and dermoid cysts may cause meningitis by releasing irritant matter into the subarachnoid space.

Pathophysiology

Meningitis typically occurs through two routes of inoculation:

Hematogenous Seeding

• Bacterial droplets colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.

Direct Contiguous Spread

• Organisms can enter the cerebrospinal fluid (CSF) via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma) or during operative procedures.

Viruses can penetrate the central nervous system (CNS) via retrograde transmission along neuronal pathways or by hematogenous seeding.

Causes of Meningitis

Several strains of bacteria can cause acute bacterial meningitis, most commonly

• Streptococcus pneumoniae (pneumococcus) – This bacterium is the most common cause of bacterial meningitis in infants, young children, and adults in the United States. It more commonly causes pneumonia or ear or sinus infections. A vaccine can help prevent this infection.
• Neisseria meningitidis (meningococcus) – This bacterium is another leading cause of bacterial meningitis. These bacteria commonly cause an upper respiratory infection but can cause meningococcal meningitis when they enter the bloodstream. This is a highly contagious infection that affects mainly teenagers and young adults. It may cause local epidemics in college dormitories, boarding schools, and military bases. A vaccine can help prevent infection.
• Haemophilus influenzae (Haemophilus) – Haemophilus influenza type b (Hib) bacterium was once the leading cause of bacterial meningitis in children. But new Hib vaccines have greatly reduced the number of cases of this type of meningitis.
• Listeria monocytogenes (listeria) – These bacteria can be found in unpasteurized cheeses, hot dogs and luncheon meats. Pregnant women, newborns, older adults and people with weakened immune systems are most susceptible.
• Fungal infection
• Syphilis
• Tuberculosis
• Autoimmune disorders
• Cancer medications
• Adults older than 60 years of age
• Children younger than 5 years of age
• People with alcoholism
• People with sickle cell anemia
• People with cancer, especially those receiving chemotherapy
• People who have received transplants and are taking drugs that suppress the immune system
• People with diabetes
• Those recently exposed to meningitis at home
• People living in close quarters (military barracks, dormitories)
• IV drug users
• People with shunts in place for hydrocephalus

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

• sneezing
• coughing
• kissing
• sharing utensils, such as cutlery
• sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases).

• a boarding school
• a university campus
• a military base
• student housing

Symptoms of Meningitis

Possible signs and symptoms in anyone older than the age of 2 include

• Sudden high fever
• Severe headache that seems different than normal
• Headache with nausea or vomiting
• Confusion or difficulty concentrating
• Stiff neck occurs in a majority of people with meningitis
• Fever and chills occur in most people with meningitis
• Vomiting occurs in many of people with meningitis
• Extreme sensitivity to bright lights (photophobia)
• Confusion
• Seizures
• History of a recent upper respiratory infection (for example, cold, sore throat)
• Drowsiness
• Sleepiness or difficulty waking
• Sensitivity to light
• No appetite or thirst
• Skin rash (sometimes, such as in meningococcal meningitis)

Signs of Meningitis in newborns 

Newborns and infants may show these signs

• High fever
• Constant crying
• Be agitated and not want to be picked up
• Have a bulging soft spot on their head (fontanelle)
• Be floppy or unresponsive
• Have an unusually high-pitched cry
• Excessive sleepiness or irritability
• Inactivity or sluggishness
• Poor feeding
• A bulge in the soft spot on top of a baby’s head (fontanel)
• Stiffness in a baby’s body and neck

Diagnosis of Meningitis

Laboratory Investigations

• Initial blood tests – should be performed for full blood count, coagulation studies, and electrolytes to assess for complications of sepsis and to guide fluid management. Serum glucose should be routinely measured as it may be low in the child with meningitis, contributing to seizures. Its measurement is also needed to accurately interpret the CSF glucose.
• Blood cultures – should be performed in all patients with suspected bacterial meningitis. They may be of particular value if a lumbar puncture is contraindicated. The likelihood of a positive blood culture result varies with the infecting organism; 40% of children with meningococcal meningitis will have a positive blood culture, whereas 50–90% of H. influenzae and 75% of S. pneumonia meningitis patients will have a positive culture result [rx].
• Both CRP and procalcitonin – have been evaluated to distinguish between viral and bacterial meningitis. Several studies have shown procalcitonin to have better diagnostic accuracy than CRP in differentiating between aseptic and bacterial meningitis [rx, rx]. Procalcitonin levels in combination with other clinical scoring systems have also been studied to evaluate the risk of bacterial meningitis [rx, rx]. Although potentially increasing the sensitivity of scoring systems, the use of procalcitonin in association with clinical scores to exclude the diagnosis of bacterial meningitis is not currently recommended

Cerebrospinal fluid biochemistry

• Cerebrospinal fluid glucose is normally approximately two-thirds of the blood (plasma) concentration. It is often lower in bacterial and tuberculous meningitis. As CSF glucose is influenced by the plasma glucose, it is essential to measure blood glucose at LP, to obtain an accurate CSF – blood glucose ratio. A CSF – blood glucose ratio <0.36 is an accurate (93%) marker for distinguishing bacterial from viral meningitis.[rx]
• Cerebrospinal fluid protein is normally <0.4 g/L. Elevated protein suggests inflammation. A CSF protein < 0.6 g/L largely rules out bacterial infection.[rx]

Common Tests Include The Following

• Chest X-rays –  can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
• A CT scan  – of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
• MRI – to be oversure about meningitis

Treatment

Immediate treatment

• Antibiotics – These are usually given intravenously.
• Corticosteroids – These may be given if inflammation is causing pressure in the brain, but studies show conflicting results.
• Acetaminophen, or paracetamol –Together with cool sponge baths, cooling pads, fluids, and room ventilation, these reduce fever.
• Anticonvulsants – If the patient has seizures, an anticonvulsant, such as phenobarbital or Dilantin, may be used.
• Oxygen therapy – Oxygen will be administered to assist with breathing.
• Fluids – Intravenous fluids can prevent dehydration, especially if the patient is vomiting or cannot drink.
• Sedatives – These will calm the patient if they are irritable or restless.

Blood tests may be used to monitor the patient’s levels of blood sugar, sodium, and other vital chemicals.

Treatment / Management

Antibiotics and supportive care are critical in all infectious resuscitations.[rx][rx][rx]

Managing the airway, maintaining oxygenation, giving sufficient intra-venous fluids while providing fever control are parts of the foundation of sepsis management.

The type of antibiotic is based on the presumed organism causing the infection. The clinician must take into account patient demographics and past medical history in order to provide the best antimicrobial coverage.

Current Empiric Therapy

Neonates – Up to 1 month old

• Ampicillin 100 mg/kg intravenously (IV) and
• Cefotaxime 75 mg/kg IV or Gentamicin 2.5 mg/kg IV and
• Acyclovir IV 40 mg/kg

More than 1 month old

• Ampicillin 50 mg/kg IV and
• Ceftriaxone 2 g IV  and
• Acyclovir IV 40 mg/kg

Adults (18 to 49 years old)

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV

Adults older than 50 years old and the immunocompromised

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV and
• Ampicillin 2 g IV

Meningitis associated with a foreign body (post-procedure, penetrating trauma)

• Cefepime 2 g IV or Ceftazidime 2 g IV or Meropenem 2 g IV and
• Vancomycin 20 mg/kg IV

Meningitis with severe penicillin allergy

• Chloramphenicol 1 g IV and
• Vancomycin 20 mg/kg IV

Fungal (Cryptococcal) meningitis

• Amphotericin B 1 mg/kg IV and
• Flucytosine 25 mg/kg by mouth

Antibiotics

Ceftriaxone

• Third-generation cephalosporin
• Gram-negative coverage
• Very effective against S. pneumoniae and N. meningitides
• Better CNS penetration than Piperacillin-Tazobactam (typically used in gram-negative sepsis coverage)

Vancomycin

• Gram-positive coverage (MRSA)
• Also used for resistant pneumococcus

Ampicillin

• Listeria coverage (gram-positive bacilli)
• Is an aminopenicillin

Cefepime

• Fourth generation cephalosporin
• Increased activity against pseudomonas

Cefotaxime

• Third generation Cephalosporin
• Safe for neonates

Steroid Therapy

Administration of dexamethasone 10 mg IV before or with the first dose of antibiotics has been shown to reduce the risk of morbidity and mortality, especially in the setting of S. pneumoniae infection.

It is important to note; the Infectious Disease Society of America recommends against dexamethasone if the patient has already received antibiotics.

Increased Intracranial Pressure

If the patient develops clinical signs of increased intracranial pressure, interventions to maintain cerebral perfusion include:

• Elevating the head of the bed to 30 degrees
• Inducing mild hyperventilation in the intubated patient
• Osmotic diuretics such as 25% mannitol or 3% saline

Chemoprophylaxis

The transmission rate of N. meningitidis is 5% for close contacts, but chemoprophylaxis within 24 hours decreases that by 89%. Thus, chemoprophylaxis is indicated for close contacts of a patient suspected of having bacterial meningitis.

Close contacts include housemates, significant others, those who have shared utensils and health care providers in proximity to secretions (providing mouth-to-mouth resuscitation, intubating without a facemask).

Antibiotic chemoprophylaxis options include:

• Rifampin 10 mg/kg (max 200 mg/dose) every 12 hours for 4 doses or
• Ciprofloxacin 500 g orally once, or
• Ceftriaxone 250 mg intramuscularly once

Prevention of Meningitis

As several types of bacteria can cause bacterial meningitis, so a range of vaccines is necessary to prevent infection.

• Haemophilus influenzae type b – can be prevented with Hib immunisation, which is available in combination vaccines free on the National Immunisation Program Schedule. It is routinely offered tor babies and needs to be purchased on prescription for some groups at high risk of bacterial disease.
• Meningococcal group A, B, C, W135 and Y – can be prevented with a range of vaccines. Some immunisation is available free on the National Immunisation Program Schedule routinely for 12 month old babies or childhood catch-up and some vaccine needs to be purchased with prescription for some groups at high risk of bacterial disease or some travellers
• Pneumococcal – can be prevented with two types of pneumococcal vaccine.. They are available free on the National Immunisation Schedule to all babies and adults 50 years of age, if the person is an Aboriginal or Torres Strait Islander, or at 65 years of age and over. They need to be purchased on prescription for some groups at high risk of bacterial disease.
• A survey of 17 million people in the U.S. found that the incidence of all types of meningitis fell by 31 percent from 1998 to 2007, after the introduction of routine vaccinations against meningitis-causing bacteria.
• The meningococcal vaccine is the primary vaccine in the U.S. All children should have this at the age of 11 to 12 years and again at 16 years, when the risk of infection is higher.
• The Hib vaccine protects children against H. Influenzae. Before its introduction in the U.S. in 1985, H. Influenzae infected over 20,000 children under 5 years annually, with a 3 to 6 percent mortality rate. Widespread vaccination has reduced the incidence of bacterial meningitis by over 99 percent.
• The Hib vaccine is given in four doses at the ages of 2, 4, 6, and 12 to 15 months.

Complication

For patients treated promptly, the prognosis is good. However, patients who present with an altered state of consciousness have a high morbidity and mortality. Some patients may develop seizures during the illness, which are very difficult to control or are prolonged. Any patient with a residual neurological deficit after meningitis treatment is also left with a disability. Patients art the greatest risk for death usually have the following features:

• Advanced aged
• Low GCS
• CSF WBC count which is low
• Tachycardia
• Gram-positive cocci in the CSF

Serious complications in survivors include:

• Ataxia
• Hearing loss
• Cranial nerve palsies
• Cognitive dysfunction
• Cortical blindness
• Hydrocephalus
• Seizures
• Focal paralysis

References

[wpedon id=”117664″ align=”center”][wpedon id=”117664″ align=”center”]

People Also Reading

Meningitis Causes Symptoms, Treatment Meningitis Symptoms, Diagnosis, Treatment Viral Meningitis, Causes, Symptoms, Treatment Parasitic Meningitis, Symptoms, Treatment Child Meningitis; Causes, Symptoms, Treatment Meningitis; Causes, Symptoms, Diagnosis, Treatment Bacterial Tracheitis – Causes, Symptoms, Treatment Typical Bacterial Pneumonia – Causes, Symptoms, Treatment Meningitis Diagnosis, Treatment, Prevention Meningitis Treatment, Prevention, Complication Fungal Meningitis, Causes, Diagnosis, Treatment Meningitis Types, Causes, Treatment, Home Tips

Meningitis Types/Meningitis is inflammation of the meninges covering the brain. It is a pathological definition. The cerebrospinal fluid (CSF) typically exhibits an elevated number of leucocytes (or a pleocytosis). In adults, >5 leucocytes/μL is defined as elevated. Bacterial or viral meningitis is confirmed by the detection of a pathogen in the CSF. Bacterial meningitis may also be suggested by symptoms of meningism and appropriate bacteria in the blood.[rx]

Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

Types of Meningitis

Bacterial

Meningitis caused by bacteria can be deadly and requires immediate medical attention. Vaccines are available to help protect against some kinds of bacterial meningitis. Streptococcus pneumoniae- A causative bacteria of meningitis.

The types of bacteria that cause bacterial meningitis vary according to the infected individual’s age group.

• In premature babies and newborns up to three months old – common causes are group B streptococci (subtypes III which normally inhabit the vagina and are mainly a cause during the first week of life) and bacteria that normally inhabit the digestive tract such as Escherichia coli (carrying the K1 antigen). Listeria monocytogenes (serotype IVb) is transmitted by the mother before birth and may cause meningitis in the newborn.
• Older children are more commonly affected by – Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (serotypes 6, 9, 14, 18 and 23) and those under five by Haemophilus influenzae type B (in countries that do not offer vaccination).
• In adults –  Neisseria meningitidis and Streptococcus pneumoniae together cause 80% of bacterial meningitis cases. Risk of infection with Listeria monocytogenes is increased in persons over 50 years old. The introduction of the pneumococcal vaccine has lowered rates of pneumococcal meningitis in both children and adults.
• Recent skull trauma potentially – allows nasal cavity bacteria to enter the meningeal space. Similarly, devices in the brain and meninges, such as cerebral shunts, extraventricular drains or Ommaya reservoirs, carry an increased risk of meningitis. In these cases, the persons are more likely to be infected with Staphylococci, Pseudomonas, and other Gram-negative bacteria. These pathogens are also associated with meningitis in people with an impaired immune system.
• Tuberculous meningitis – which is meningitis caused by Mycobacterium tuberculosis, is more common in people from countries in which tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS.

Viral

• Meningitis caused by viruses is serious but often is less severe than bacterial meningitis. People with normal immune systems who get viral meningitis usually get better on their own. There are vaccines to prevent some kinds of viral meningitis.
• Viruses that cause meningitis include enteroviruses, herpes simplex virus (generally type 2, which produces most genital sores; less commonly type 1), varicella zoster virus (known for causing chickenpox and shingles), mumps virus, HIV, and LCMV. Mollaret’s meningitis is a chronic recurrent form of herpes meningitis; it is thought to be caused by herpes simplex virus type 2.

Fungal

• Meningitis caused by fungi is rare, but people can get it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
• There are a number of risk factors for fungal meningitis, including the use of immunosuppressants (such as after organ transplantation), HIV/AIDS, and the loss of immunity associated with aging. It is uncommon in those with a normal immune system but has occurred with medication contamination.
• Symptom onset is typically more gradual, with headaches and fever being present for at least a couple of weeks before diagnosis. The most common fungal meningitis is cryptococcal meningitis due to Cryptococcus neoformans.
• In Africa, cryptococcal meningitis is now the most common cause of meningitis in multiple studies, and it accounts for 20–25% of AIDS-related deaths in Africa. Other less common fungal pathogens which can cause meningitis include: Coccidioides immitis, Histoplasma capsulatum, Blastomyces dermatitidis, and Candidaspecies.

Parasitic

• Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Overall, parasitic meningitis is much less common than viral and bacterial meningitis.
• A parasitic cause is often assumed when there is a predominance of eosinophils (a type of white blood cell) in the CSF. The most common parasites implicated are Angiostrongylus cantonensis, Gnathostoma spinigerum, Schistosoma, as well as the conditions cysticercosis, toxocariasis, baylisascariasis, paragonimiasis, and a number of rarer infections and noninfective conditions.

Aseptic meningitis

Aseptic meningitis is a term referring to the broad category of meningitis that is not caused by bacteria. Approximately 50% of aseptic meningitis is due to viral infections. Other less common causes include

• drug reactions or allergies, and
• inflammatory diseases like lupus.

Non-infectious

• Meningitis may occur as the result of several non-infectious causes: the spread of cancer to the meninges (malignant or neoplastic meningitis) and certain drugs (mainly non-steroidal anti-inflammatory drugs, antibiotics and intravenous immunoglobulins).
• It may also be caused by several inflammatory conditions, such as sarcoidosis (which is then called neurosarcoidosis), connective tissue disorders such as systemic lupus erythematosus, and certain forms of vasculitis (inflammatory conditions of the blood vessel wall), such as Behçet’s disease. Epidermoid cysts and dermoid cysts may cause meningitis by releasing irritant matter into the subarachnoid space.

Pathophysiology

Meningitis typically occurs through two routes of inoculation:

Hematogenous Seeding

• Bacterial droplets colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.

Direct Contiguous Spread

• Organisms can enter the cerebrospinal fluid (CSF) via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma) or during operative procedures.

Viruses can penetrate the central nervous system (CNS) via retrograde transmission along neuronal pathways or by hematogenous seeding.

Causes of Meningitis

Several strains of bacteria can cause acute bacterial meningitis, most commonly

• Streptococcus pneumoniae (pneumococcus) – This bacterium is the most common cause of bacterial meningitis in infants, young children, and adults in the United States. It more commonly causes pneumonia or ear or sinus infections. A vaccine can help prevent this infection.
• Neisseria meningitidis (meningococcus) – This bacterium is another leading cause of bacterial meningitis. These bacteria commonly cause an upper respiratory infection but can cause meningococcal meningitis when they enter the bloodstream. This is a highly contagious infection that affects mainly teenagers and young adults. It may cause local epidemics in college dormitories, boarding schools, and military bases. A vaccine can help prevent infection.
• Haemophilus influenzae (Haemophilus) – Haemophilus influenza type b (Hib) bacterium was once the leading cause of bacterial meningitis in children. But new Hib vaccines have greatly reduced the number of cases of this type of meningitis.
• Listeria monocytogenes (listeria) – These bacteria can be found in unpasteurized cheeses, hot dogs and luncheon meats. Pregnant women, newborns, older adults and people with weakened immune systems are most susceptible.
• Fungal infection
• Syphilis
• Tuberculosis
• Autoimmune disorders
• Cancer medications
• Adults older than 60 years of age
• Children younger than 5 years of age
• People with alcoholism
• People with sickle cell anemia
• People with cancer, especially those receiving chemotherapy
• People who have received transplants and are taking drugs that suppress the immune system
• People with diabetes
• Those recently exposed to meningitis at home
• People living in close quarters (military barracks, dormitories)
• IV drug users
• People with shunts in place for hydrocephalus

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

• sneezing
• coughing
• kissing
• sharing utensils, such as cutlery
• sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases).

• a boarding school
• a university campus
• a military base
• student housing

Symptoms of Meningitis

Possible signs and symptoms in anyone older than the age of 2 include

• Sudden high fever
• Severe headache that seems different than normal
• Headache with nausea or vomiting
• Confusion or difficulty concentrating
• Stiff neck occurs in a majority of people with meningitis
• Fever and chills occur in most people with meningitis
• Vomiting occurs in many of people with meningitis
• Extreme sensitivity to bright lights (photophobia)
• Confusion
• Seizures
• History of a recent upper respiratory infection (for example, cold, sore throat)
• Drowsiness
• Sleepiness or difficulty waking
• Sensitivity to light
• No appetite or thirst
• Skin rash (sometimes, such as in meningococcal meningitis)

Signs of Meningitis in newborns 

Newborns and infants may show these signs

• High fever
• Constant crying
• Be agitated and not want to be picked up
• Have a bulging soft spot on their head (fontanelle)
• Be floppy or unresponsive
• Have an unusually high-pitched cry
• Excessive sleepiness or irritability
• Inactivity or sluggishness
• Poor feeding
• A bulge in the soft spot on top of a baby’s head (fontanel)
• Stiffness in a baby’s body and neck

Diagnosis of Meningitis

Laboratory Investigations

• Initial blood tests – should be performed for full blood count, coagulation studies, and electrolytes to assess for complications of sepsis and to guide fluid management. Serum glucose should be routinely measured as it may be low in the child with meningitis, contributing to seizures. Its measurement is also needed to accurately interpret the CSF glucose.
• Blood cultures – should be performed in all patients with suspected bacterial meningitis. They may be of particular value if a lumbar puncture is contraindicated. The likelihood of a positive blood culture result varies with the infecting organism; 40% of children with meningococcal meningitis will have a positive blood culture, whereas 50–90% of H. influenzae and 75% of S. pneumonia meningitis patients will have a positive culture result [rx].
• Both CRP and procalcitonin – have been evaluated to distinguish between viral and bacterial meningitis. Several studies have shown procalcitonin to have better diagnostic accuracy than CRP in differentiating between aseptic and bacterial meningitis [rx, rx]. Procalcitonin levels in combination with other clinical scoring systems have also been studied to evaluate the risk of bacterial meningitis [rx, rx]. Although potentially increasing the sensitivity of scoring systems, the use of procalcitonin in association with clinical scores to exclude the diagnosis of bacterial meningitis is not currently recommended

Cerebrospinal fluid biochemistry

• Cerebrospinal fluid glucose is normally approximately two-thirds of the blood (plasma) concentration. It is often lower in bacterial and tuberculous meningitis. As CSF glucose is influenced by the plasma glucose, it is essential to measure blood glucose at LP, to obtain an accurate CSF – blood glucose ratio. A CSF – blood glucose ratio <0.36 is an accurate (93%) marker for distinguishing bacterial from viral meningitis.[rx]
• Cerebrospinal fluid protein is normally <0.4 g/L. Elevated protein suggests inflammation. A CSF protein < 0.6 g/L largely rules out bacterial infection.[rx]

Common Tests Include The Following

• Chest X-rays –  can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
• A CT scan  – of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
• MRI – to be oversure about meningitis

Treatment

Immediate treatment

• Antibiotics – These are usually given intravenously.
• Corticosteroids – These may be given if inflammation is causing pressure in the brain, but studies show conflicting results.
• Acetaminophen, or paracetamol –Together with cool sponge baths, cooling pads, fluids, and room ventilation, these reduce fever.
• Anticonvulsants – If the patient has seizures, an anticonvulsant, such as phenobarbital or Dilantin, may be used.
• Oxygen therapy – Oxygen will be administered to assist with breathing.
• Fluids – Intravenous fluids can prevent dehydration, especially if the patient is vomiting or cannot drink.
• Sedatives – These will calm the patient if they are irritable or restless.

Blood tests may be used to monitor the patient’s levels of blood sugar, sodium, and other vital chemicals.

Treatment / Management

Antibiotics and supportive care are critical in all infectious resuscitations.[rx][rx][rx]

Managing the airway, maintaining oxygenation, giving sufficient intra-venous fluids while providing fever control are parts of the foundation of sepsis management.

The type of antibiotic is based on the presumed organism causing the infection. The clinician must take into account patient demographics and past medical history in order to provide the best antimicrobial coverage.

Current Empiric Therapy

Neonates – Up to 1 month old

• Ampicillin 100 mg/kg intravenously (IV) and
• Cefotaxime 75 mg/kg IV or Gentamicin 2.5 mg/kg IV and
• Acyclovir IV 40 mg/kg

More than 1 month old

• Ampicillin 50 mg/kg IV and
• Ceftriaxone 2 g IV  and
• Acyclovir IV 40 mg/kg

Adults (18 to 49 years old)

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV

Adults older than 50 years old and the immunocompromised

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV and
• Ampicillin 2 g IV

Meningitis associated with a foreign body (post-procedure, penetrating trauma)

• Cefepime 2 g IV or Ceftazidime 2 g IV or Meropenem 2 g IV and
• Vancomycin 20 mg/kg IV

Meningitis with severe penicillin allergy

• Chloramphenicol 1 g IV and
• Vancomycin 20 mg/kg IV

Fungal (Cryptococcal) meningitis

• Amphotericin B 1 mg/kg IV and
• Flucytosine 25 mg/kg by mouth

Antibiotics

Ceftriaxone

• Third-generation cephalosporin
• Gram-negative coverage
• Very effective against S. pneumoniae and N. meningitides
• Better CNS penetration than Piperacillin-Tazobactam (typically used in gram-negative sepsis coverage)

Vancomycin

• Gram-positive coverage (MRSA)
• Also used for resistant pneumococcus

Ampicillin

• Listeria coverage (gram-positive bacilli)
• Is an aminopenicillin

Cefepime

• Fourth generation cephalosporin
• Increased activity against pseudomonas

Cefotaxime

• Third generation Cephalosporin
• Safe for neonates

Steroid Therapy

Administration of dexamethasone 10 mg IV before or with the first dose of antibiotics has been shown to reduce the risk of morbidity and mortality, especially in the setting of S. pneumoniae infection.

It is important to note; the Infectious Disease Society of America recommends against dexamethasone if the patient has already received antibiotics.

Increased Intracranial Pressure

If the patient develops clinical signs of increased intracranial pressure, interventions to maintain cerebral perfusion include:

• Elevating the head of the bed to 30 degrees
• Inducing mild hyperventilation in the intubated patient
• Osmotic diuretics such as 25% mannitol or 3% saline

Chemoprophylaxis

The transmission rate of N. meningitidis is 5% for close contacts, but chemoprophylaxis within 24 hours decreases that by 89%. Thus, chemoprophylaxis is indicated for close contacts of a patient suspected of having bacterial meningitis.

Close contacts include housemates, significant others, those who have shared utensils and health care providers in proximity to secretions (providing mouth-to-mouth resuscitation, intubating without a facemask).

Antibiotic chemoprophylaxis options include:

• Rifampin 10 mg/kg (max 200 mg/dose) every 12 hours for 4 doses or
• Ciprofloxacin 500 g orally once, or
• Ceftriaxone 250 mg intramuscularly once

Prevention of Meningitis

As several types of bacteria can cause bacterial meningitis, so a range of vaccines is necessary to prevent infection.

• Haemophilus influenzae type b – can be prevented with Hib immunisation, which is available in combination vaccines free on the National Immunisation Program Schedule. It is routinely offered tor babies and needs to be purchased on prescription for some groups at high risk of bacterial disease.
• Meningococcal group A, B, C, W135 and Y – can be prevented with a range of vaccines. Some immunisation is available free on the National Immunisation Program Schedule routinely for 12 month old babies or childhood catch-up and some vaccine needs to be purchased with prescription for some groups at high risk of bacterial disease or some travellers
• Pneumococcal – can be prevented with two types of pneumococcal vaccine.. They are available free on the National Immunisation Schedule to all babies and adults 50 years of age, if the person is an Aboriginal or Torres Strait Islander, or at 65 years of age and over. They need to be purchased on prescription for some groups at high risk of bacterial disease.
• A survey of 17 million people in the U.S. found that the incidence of all types of meningitis fell by 31 percent from 1998 to 2007, after the introduction of routine vaccinations against meningitis-causing bacteria.
• The meningococcal vaccine is the primary vaccine in the U.S. All children should have this at the age of 11 to 12 years and again at 16 years, when the risk of infection is higher.
• The Hib vaccine protects children against H. Influenzae. Before its introduction in the U.S. in 1985, H. Influenzae infected over 20,000 children under 5 years annually, with a 3 to 6 percent mortality rate. Widespread vaccination has reduced the incidence of bacterial meningitis by over 99 percent.
• The Hib vaccine is given in four doses at the ages of 2, 4, 6, and 12 to 15 months.

Complication

For patients treated promptly, the prognosis is good. However, patients who present with an altered state of consciousness have a high morbidity and mortality. Some patients may develop seizures during the illness, which are very difficult to control or are prolonged. Any patient with a residual neurological deficit after meningitis treatment is also left with a disability. Patients art the greatest risk for death usually have the following features:

• Advanced aged
• Low GCS
• CSF WBC count which is low
• Tachycardia
• Gram-positive cocci in the CSF

Serious complications in survivors include:

• Ataxia
• Hearing loss
• Cranial nerve palsies
• Cognitive dysfunction
• Cortical blindness
• Hydrocephalus
• Seizures
• Focal paralysis

References

[wpedon id=”117664″ align=”center”][wpedon id=”117664″ align=”center”]

People Also Reading

Meningitis Causes Symptoms, Treatment Bacterial Meningitis, Causes, Symptoms, Treatment Meningitis Symptoms, Diagnosis, Treatment Meningitis Diagnosis, Treatment, Prevention Meningitis Treatment, Prevention, Complication Fungal Meningitis, Causes, Diagnosis, Treatment Viral Meningitis, Causes, Symptoms, Treatment Parasitic Meningitis, Symptoms, Treatment Treatment of Meningitis, Treatment, Prevention Strep Throat Treatment, Surgery, Home Tips Vitamin E Food Source, Types, Home Tips Child Meningitis; Causes, Symptoms, Treatment

Meningitis Treatment/Meningitis is inflammation of the meninges covering the brain. It is a pathological definition. The cerebrospinal fluid (CSF) typically exhibits an elevated number of leucocytes (or a pleocytosis). In adults, >5 leucocytes/μL is defined as elevated. Bacterial or viral meningitis is confirmed by the detection of a pathogen in the CSF. Bacterial meningitis may also be suggested by symptoms of meningism and appropriate bacteria in the blood.[rx]

Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

Types of Meningitis

Bacterial

Meningitis caused by bacteria can be deadly and requires immediate medical attention. Vaccines are available to help protect against some kinds of bacterial meningitis. Streptococcus pneumoniae- A causative bacteria of meningitis.

The types of bacteria that cause bacterial meningitis vary according to the infected individual’s age group.

• In premature babies and newborns up to three months old – common causes are group B streptococci (subtypes III which normally inhabit the vagina and are mainly a cause during the first week of life) and bacteria that normally inhabit the digestive tract such as Escherichia coli (carrying the K1 antigen). Listeria monocytogenes (serotype IVb) is transmitted by the mother before birth and may cause meningitis in the newborn.
• Older children are more commonly affected by – Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (serotypes 6, 9, 14, 18 and 23) and those under five by Haemophilus influenzae type B (in countries that do not offer vaccination).
• In adults –  Neisseria meningitidis and Streptococcus pneumoniae together cause 80% of bacterial meningitis cases. Risk of infection with Listeria monocytogenes is increased in persons over 50 years old. The introduction of the pneumococcal vaccine has lowered rates of pneumococcal meningitis in both children and adults.
• Recent skull trauma potentially – allows nasal cavity bacteria to enter the meningeal space. Similarly, devices in the brain and meninges, such as cerebral shunts, extraventricular drains or Ommaya reservoirs, carry an increased risk of meningitis. In these cases, the persons are more likely to be infected with Staphylococci, Pseudomonas, and other Gram-negative bacteria. These pathogens are also associated with meningitis in people with an impaired immune system.
• Tuberculous meningitis – which is meningitis caused by Mycobacterium tuberculosis, is more common in people from countries in which tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS.

Viral

• Meningitis caused by viruses is serious but often is less severe than bacterial meningitis. People with normal immune systems who get viral meningitis usually get better on their own. There are vaccines to prevent some kinds of viral meningitis.
• Viruses that cause meningitis include enteroviruses, herpes simplex virus (generally type 2, which produces most genital sores; less commonly type 1), varicella zoster virus (known for causing chickenpox and shingles), mumps virus, HIV, and LCMV. Mollaret’s meningitis is a chronic recurrent form of herpes meningitis; it is thought to be caused by herpes simplex virus type 2.

Fungal

• Meningitis caused by fungi is rare, but people can get it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
• There are a number of risk factors for fungal meningitis, including the use of immunosuppressants (such as after organ transplantation), HIV/AIDS, and the loss of immunity associated with aging. It is uncommon in those with a normal immune system but has occurred with medication contamination.
• Symptom onset is typically more gradual, with headaches and fever being present for at least a couple of weeks before diagnosis. The most common fungal meningitis is cryptococcal meningitis due to Cryptococcus neoformans.
• In Africa, cryptococcal meningitis is now the most common cause of meningitis in multiple studies, and it accounts for 20–25% of AIDS-related deaths in Africa. Other less common fungal pathogens which can cause meningitis include: Coccidioides immitis, Histoplasma capsulatum, Blastomyces dermatitidis, and Candidaspecies.

Parasitic

• Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Overall, parasitic meningitis is much less common than viral and bacterial meningitis.
• A parasitic cause is often assumed when there is a predominance of eosinophils (a type of white blood cell) in the CSF. The most common parasites implicated are Angiostrongylus cantonensis, Gnathostoma spinigerum, Schistosoma, as well as the conditions cysticercosis, toxocariasis, baylisascariasis, paragonimiasis, and a number of rarer infections and noninfective conditions.

Aseptic meningitis

Aseptic meningitis is a term referring to the broad category of meningitis that is not caused by bacteria. Approximately 50% of aseptic meningitis is due to viral infections. Other less common causes include

• drug reactions or allergies, and
• inflammatory diseases like lupus.

Non-infectious

• Meningitis may occur as the result of several non-infectious causes: the spread of cancer to the meninges (malignant or neoplastic meningitis) and certain drugs (mainly non-steroidal anti-inflammatory drugs, antibiotics and intravenous immunoglobulins).
• It may also be caused by several inflammatory conditions, such as sarcoidosis (which is then called neurosarcoidosis), connective tissue disorders such as systemic lupus erythematosus, and certain forms of vasculitis (inflammatory conditions of the blood vessel wall), such as Behçet’s disease. Epidermoid cysts and dermoid cysts may cause meningitis by releasing irritant matter into the subarachnoid space.

Pathophysiology

Meningitis typically occurs through two routes of inoculation:

Hematogenous Seeding

• Bacterial droplets colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.

Direct Contiguous Spread

• Organisms can enter the cerebrospinal fluid (CSF) via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma) or during operative procedures.

Viruses can penetrate the central nervous system (CNS) via retrograde transmission along neuronal pathways or by hematogenous seeding.

Causes of Meningitis

Several strains of bacteria can cause acute bacterial meningitis, most commonly

• Streptococcus pneumoniae (pneumococcus) – This bacterium is the most common cause of bacterial meningitis in infants, young children, and adults in the United States. It more commonly causes pneumonia or ear or sinus infections. A vaccine can help prevent this infection.
• Neisseria meningitidis (meningococcus) – This bacterium is another leading cause of bacterial meningitis. These bacteria commonly cause an upper respiratory infection but can cause meningococcal meningitis when they enter the bloodstream. This is a highly contagious infection that affects mainly teenagers and young adults. It may cause local epidemics in college dormitories, boarding schools, and military bases. A vaccine can help prevent infection.
• Haemophilus influenzae (Haemophilus) – Haemophilus influenza type b (Hib) bacterium was once the leading cause of bacterial meningitis in children. But new Hib vaccines have greatly reduced the number of cases of this type of meningitis.
• Listeria monocytogenes (listeria) – These bacteria can be found in unpasteurized cheeses, hot dogs and luncheon meats. Pregnant women, newborns, older adults and people with weakened immune systems are most susceptible.
• Fungal infection
• Syphilis
• Tuberculosis
• Autoimmune disorders
• Cancer medications
• Adults older than 60 years of age
• Children younger than 5 years of age
• People with alcoholism
• People with sickle cell anemia
• People with cancer, especially those receiving chemotherapy
• People who have received transplants and are taking drugs that suppress the immune system
• People with diabetes
• Those recently exposed to meningitis at home
• People living in close quarters (military barracks, dormitories)
• IV drug users
• People with shunts in place for hydrocephalus

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

• sneezing
• coughing
• kissing
• sharing utensils, such as cutlery
• sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases).

• a boarding school
• a university campus
• a military base
• student housing

Symptoms of Meningitis

Possible signs and symptoms in anyone older than the age of 2 include

• Sudden high fever
• Severe headache that seems different than normal
• Headache with nausea or vomiting
• Confusion or difficulty concentrating
• Stiff neck occurs in a majority of people with meningitis
• Fever and chills occur in most people with meningitis
• Vomiting occurs in many of people with meningitis
• Extreme sensitivity to bright lights (photophobia)
• Confusion
• Seizures
• History of a recent upper respiratory infection (for example, cold, sore throat)
• Drowsiness
• Sleepiness or difficulty waking
• Sensitivity to light
• No appetite or thirst
• Skin rash (sometimes, such as in meningococcal meningitis)

Signs of Meningitis in newborns 

Newborns and infants may show these signs

• High fever
• Constant crying
• Be agitated and not want to be picked up
• Have a bulging soft spot on their head (fontanelle)
• Be floppy or unresponsive
• Have an unusually high-pitched cry
• Excessive sleepiness or irritability
• Inactivity or sluggishness
• Poor feeding
• A bulge in the soft spot on top of a baby’s head (fontanel)
• Stiffness in a baby’s body and neck

Diagnosis of Meningitis

Laboratory Investigations

• Initial blood tests – should be performed for full blood count, coagulation studies, and electrolytes to assess for complications of sepsis and to guide fluid management. Serum glucose should be routinely measured as it may be low in the child with meningitis, contributing to seizures. Its measurement is also needed to accurately interpret the CSF glucose.
• Blood cultures – should be performed in all patients with suspected bacterial meningitis. They may be of particular value if a lumbar puncture is contraindicated. The likelihood of a positive blood culture result varies with the infecting organism; 40% of children with meningococcal meningitis will have a positive blood culture, whereas 50–90% of H. influenzae and 75% of S. pneumonia meningitis patients will have a positive culture result [rx].
• Both CRP and procalcitonin – have been evaluated to distinguish between viral and bacterial meningitis. Several studies have shown procalcitonin to have better diagnostic accuracy than CRP in differentiating between aseptic and bacterial meningitis [rx, rx]. Procalcitonin levels in combination with other clinical scoring systems have also been studied to evaluate the risk of bacterial meningitis [rx, rx]. Although potentially increasing the sensitivity of scoring systems, the use of procalcitonin in association with clinical scores to exclude the diagnosis of bacterial meningitis is not currently recommended

Cerebrospinal fluid biochemistry

• Cerebrospinal fluid glucose is normally approximately two-thirds of the blood (plasma) concentration. It is often lower in bacterial and tuberculous meningitis. As CSF glucose is influenced by the plasma glucose, it is essential to measure blood glucose at LP, to obtain an accurate CSF – blood glucose ratio. A CSF – blood glucose ratio <0.36 is an accurate (93%) marker for distinguishing bacterial from viral meningitis.[rx]
• Cerebrospinal fluid protein is normally <0.4 g/L. Elevated protein suggests inflammation. A CSF protein < 0.6 g/L largely rules out bacterial infection.[rx]

Common Tests Include The Following

• Chest X-rays –  can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
• A CT scan  – of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
• MRI – to be oversure about meningitis

Treatment

Immediate treatment

• Antibiotics – These are usually given intravenously.
• Corticosteroids – These may be given if inflammation is causing pressure in the brain, but studies show conflicting results.
• Acetaminophen, or paracetamol –Together with cool sponge baths, cooling pads, fluids, and room ventilation, these reduce fever.
• Anticonvulsants – If the patient has seizures, an anticonvulsant, such as phenobarbital or Dilantin, may be used.
• Oxygen therapy – Oxygen will be administered to assist with breathing.
• Fluids – Intravenous fluids can prevent dehydration, especially if the patient is vomiting or cannot drink.
• Sedatives – These will calm the patient if they are irritable or restless.

Blood tests may be used to monitor the patient’s levels of blood sugar, sodium, and other vital chemicals.

Treatment / Management

Antibiotics and supportive care are critical in all infectious resuscitations.[rx][rx][rx]

Managing the airway, maintaining oxygenation, giving sufficient intra-venous fluids while providing fever control are parts of the foundation of sepsis management.

The type of antibiotic is based on the presumed organism causing the infection. The clinician must take into account patient demographics and past medical history in order to provide the best antimicrobial coverage.

Current Empiric Therapy

Neonates – Up to 1 month old

• Ampicillin 100 mg/kg intravenously (IV) and
• Cefotaxime 75 mg/kg IV or Gentamicin 2.5 mg/kg IV and
• Acyclovir IV 40 mg/kg

More than 1 month old

• Ampicillin 50 mg/kg IV and
• Ceftriaxone 2 g IV  and
• Acyclovir IV 40 mg/kg

Adults (18 to 49 years old)

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV

Adults older than 50 years old and the immunocompromised

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV and
• Ampicillin 2 g IV

Meningitis associated with a foreign body (post-procedure, penetrating trauma)

• Cefepime 2 g IV or Ceftazidime 2 g IV or Meropenem 2 g IV and
• Vancomycin 20 mg/kg IV

Meningitis with severe penicillin allergy

• Chloramphenicol 1 g IV and
• Vancomycin 20 mg/kg IV

Fungal (Cryptococcal) meningitis

• Amphotericin B 1 mg/kg IV and
• Flucytosine 25 mg/kg by mouth

Antibiotics

Ceftriaxone

• Third-generation cephalosporin
• Gram-negative coverage
• Very effective against S. pneumoniae and N. meningitides
• Better CNS penetration than Piperacillin-Tazobactam (typically used in gram-negative sepsis coverage)

Vancomycin

• Gram-positive coverage (MRSA)
• Also used for resistant pneumococcus

Ampicillin

• Listeria coverage (gram-positive bacilli)
• Is an aminopenicillin

Cefepime

• Fourth generation cephalosporin
• Increased activity against pseudomonas

Cefotaxime

• Third generation Cephalosporin
• Safe for neonates

Steroid Therapy

Administration of dexamethasone 10 mg IV before or with the first dose of antibiotics has been shown to reduce the risk of morbidity and mortality, especially in the setting of S. pneumoniae infection.

It is important to note; the Infectious Disease Society of America recommends against dexamethasone if the patient has already received antibiotics.

Increased Intracranial Pressure

If the patient develops clinical signs of increased intracranial pressure, interventions to maintain cerebral perfusion include:

• Elevating the head of the bed to 30 degrees
• Inducing mild hyperventilation in the intubated patient
• Osmotic diuretics such as 25% mannitol or 3% saline

Chemoprophylaxis

The transmission rate of N. meningitidis is 5% for close contacts, but chemoprophylaxis within 24 hours decreases that by 89%. Thus, chemoprophylaxis is indicated for close contacts of a patient suspected of having bacterial meningitis.

Close contacts include housemates, significant others, those who have shared utensils and health care providers in proximity to secretions (providing mouth-to-mouth resuscitation, intubating without a facemask).

Antibiotic chemoprophylaxis options include:

• Rifampin 10 mg/kg (max 200 mg/dose) every 12 hours for 4 doses or
• Ciprofloxacin 500 g orally once, or
• Ceftriaxone 250 mg intramuscularly once

Prevention of Meningitis

As several types of bacteria can cause bacterial meningitis, so a range of vaccines is necessary to prevent infection.

• Haemophilus influenzae type b – can be prevented with Hib immunisation, which is available in combination vaccines free on the National Immunisation Program Schedule. It is routinely offered tor babies and needs to be purchased on prescription for some groups at high risk of bacterial disease.
• Meningococcal group A, B, C, W135 and Y – can be prevented with a range of vaccines. Some immunisation is available free on the National Immunisation Program Schedule routinely for 12 month old babies or childhood catch-up and some vaccine needs to be purchased with prescription for some groups at high risk of bacterial disease or some travellers
• Pneumococcal – can be prevented with two types of pneumococcal vaccine.. They are available free on the National Immunisation Schedule to all babies and adults 50 years of age, if the person is an Aboriginal or Torres Strait Islander, or at 65 years of age and over. They need to be purchased on prescription for some groups at high risk of bacterial disease.
• A survey of 17 million people in the U.S. found that the incidence of all types of meningitis fell by 31 percent from 1998 to 2007, after the introduction of routine vaccinations against meningitis-causing bacteria.
• The meningococcal vaccine is the primary vaccine in the U.S. All children should have this at the age of 11 to 12 years and again at 16 years, when the risk of infection is higher.
• The Hib vaccine protects children against H. Influenzae. Before its introduction in the U.S. in 1985, H. Influenzae infected over 20,000 children under 5 years annually, with a 3 to 6 percent mortality rate. Widespread vaccination has reduced the incidence of bacterial meningitis by over 99 percent.
• The Hib vaccine is given in four doses at the ages of 2, 4, 6, and 12 to 15 months.

Complication

For patients treated promptly, the prognosis is good. However, patients who present with an altered state of consciousness have a high morbidity and mortality. Some patients may develop seizures during the illness, which are very difficult to control or are prolonged. Any patient with a residual neurological deficit after meningitis treatment is also left with a disability. Patients art the greatest risk for death usually have the following features:

• Advanced aged
• Low GCS
• CSF WBC count which is low
• Tachycardia
• Gram-positive cocci in the CSF

Serious complications in survivors include:

• Ataxia
• Hearing loss
• Cranial nerve palsies
• Cognitive dysfunction
• Cortical blindness
• Hydrocephalus
• Seizures
• Focal paralysis

References

[wpedon id=”117664″ align=”center”]

People Also Reading

Meningitis Diagnosis, Treatment, Prevention Treatment of Meningitis, Treatment, Prevention Treatment of Wheezing, Prevention, Complication Meningitis Causes Symptoms, Treatment Bacterial Meningitis, Causes, Symptoms, Treatment Meningitis Symptoms, Diagnosis, Treatment Fungal Meningitis, Causes, Diagnosis, Treatment Viral Meningitis, Causes, Symptoms, Treatment Parasitic Meningitis, Symptoms, Treatment Fluid Retention Treatment, Complication, Prevention Meningitis Types, Causes, Treatment, Home Tips Conjunctivitis Treatment, Complication, Prevention

Meningitis Diagnosis/Meningitis is inflammation of the meninges covering the brain. It is a pathological definition. The cerebrospinal fluid (CSF) typically exhibits an elevated number of leucocytes (or a pleocytosis). In adults, >5 leucocytes/μL is defined as elevated. Bacterial or viral meningitis is confirmed by the detection of a pathogen in the CSF. Bacterial meningitis may also be suggested by symptoms of meningism and appropriate bacteria in the blood.[rx]

Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

Types of Meningitis

Bacterial

Meningitis caused by bacteria can be deadly and requires immediate medical attention. Vaccines are available to help protect against some kinds of bacterial meningitis. Streptococcus pneumoniae- A causative bacteria of meningitis.

The types of bacteria that cause bacterial meningitis vary according to the infected individual’s age group.

• In premature babies and newborns up to three months old – common causes are group B streptococci (subtypes III which normally inhabit the vagina and are mainly a cause during the first week of life) and bacteria that normally inhabit the digestive tract such as Escherichia coli (carrying the K1 antigen). Listeria monocytogenes (serotype IVb) is transmitted by the mother before birth and may cause meningitis in the newborn.
• Older children are more commonly affected by – Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (serotypes 6, 9, 14, 18 and 23) and those under five by Haemophilus influenzae type B (in countries that do not offer vaccination).
• In adults –  Neisseria meningitidis and Streptococcus pneumoniae together cause 80% of bacterial meningitis cases. Risk of infection with Listeria monocytogenes is increased in persons over 50 years old. The introduction of the pneumococcal vaccine has lowered rates of pneumococcal meningitis in both children and adults.
• Recent skull trauma potentially – allows nasal cavity bacteria to enter the meningeal space. Similarly, devices in the brain and meninges, such as cerebral shunts, extraventricular drains or Ommaya reservoirs, carry an increased risk of meningitis. In these cases, the persons are more likely to be infected with Staphylococci, Pseudomonas, and other Gram-negative bacteria. These pathogens are also associated with meningitis in people with an impaired immune system.
• Tuberculous meningitis – which is meningitis caused by Mycobacterium tuberculosis, is more common in people from countries in which tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS.

Viral

• Meningitis caused by viruses is serious but often is less severe than bacterial meningitis. People with normal immune systems who get viral meningitis usually get better on their own. There are vaccines to prevent some kinds of viral meningitis.
• Viruses that cause meningitis include enteroviruses, herpes simplex virus (generally type 2, which produces most genital sores; less commonly type 1), varicella zoster virus (known for causing chickenpox and shingles), mumps virus, HIV, and LCMV. Mollaret’s meningitis is a chronic recurrent form of herpes meningitis; it is thought to be caused by herpes simplex virus type 2.

Fungal

• Meningitis caused by fungi is rare, but people can get it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
• There are a number of risk factors for fungal meningitis, including the use of immunosuppressants (such as after organ transplantation), HIV/AIDS, and the loss of immunity associated with aging. It is uncommon in those with a normal immune system but has occurred with medication contamination.
• Symptom onset is typically more gradual, with headaches and fever being present for at least a couple of weeks before diagnosis. The most common fungal meningitis is cryptococcal meningitis due to Cryptococcus neoformans.
• In Africa, cryptococcal meningitis is now the most common cause of meningitis in multiple studies, and it accounts for 20–25% of AIDS-related deaths in Africa. Other less common fungal pathogens which can cause meningitis include: Coccidioides immitis, Histoplasma capsulatum, Blastomyces dermatitidis, and Candidaspecies.

Parasitic

• Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Overall, parasitic meningitis is much less common than viral and bacterial meningitis.
• A parasitic cause is often assumed when there is a predominance of eosinophils (a type of white blood cell) in the CSF. The most common parasites implicated are Angiostrongylus cantonensis, Gnathostoma spinigerum, Schistosoma, as well as the conditions cysticercosis, toxocariasis, baylisascariasis, paragonimiasis, and a number of rarer infections and noninfective conditions.

Aseptic meningitis

Aseptic meningitis is a term referring to the broad category of meningitis that is not caused by bacteria. Approximately 50% of aseptic meningitis is due to viral infections. Other less common causes include

• drug reactions or allergies, and
• inflammatory diseases like lupus.

Non-infectious

• Meningitis may occur as the result of several non-infectious causes: the spread of cancer to the meninges (malignant or neoplastic meningitis) and certain drugs (mainly non-steroidal anti-inflammatory drugs, antibiotics and intravenous immunoglobulins).
• It may also be caused by several inflammatory conditions, such as sarcoidosis (which is then called neurosarcoidosis), connective tissue disorders such as systemic lupus erythematosus, and certain forms of vasculitis (inflammatory conditions of the blood vessel wall), such as Behçet’s disease. Epidermoid cysts and dermoid cysts may cause meningitis by releasing irritant matter into the subarachnoid space.

Pathophysiology

Meningitis typically occurs through two routes of inoculation:

Hematogenous Seeding

• Bacterial droplets colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.

Direct Contiguous Spread

• Organisms can enter the cerebrospinal fluid (CSF) via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma) or during operative procedures.

Viruses can penetrate the central nervous system (CNS) via retrograde transmission along neuronal pathways or by hematogenous seeding.

Causes of Meningitis

Several strains of bacteria can cause acute bacterial meningitis, most commonly

• Streptococcus pneumoniae (pneumococcus) – This bacterium is the most common cause of bacterial meningitis in infants, young children, and adults in the United States. It more commonly causes pneumonia or ear or sinus infections. A vaccine can help prevent this infection.
• Neisseria meningitidis (meningococcus) – This bacterium is another leading cause of bacterial meningitis. These bacteria commonly cause an upper respiratory infection but can cause meningococcal meningitis when they enter the bloodstream. This is a highly contagious infection that affects mainly teenagers and young adults. It may cause local epidemics in college dormitories, boarding schools, and military bases. A vaccine can help prevent infection.
• Haemophilus influenzae (Haemophilus) – Haemophilus influenza type b (Hib) bacterium was once the leading cause of bacterial meningitis in children. But new Hib vaccines have greatly reduced the number of cases of this type of meningitis.
• Listeria monocytogenes (listeria) – These bacteria can be found in unpasteurized cheeses, hot dogs and luncheon meats. Pregnant women, newborns, older adults and people with weakened immune systems are most susceptible.
• Fungal infection
• Syphilis
• Tuberculosis
• Autoimmune disorders
• Cancer medications
• Adults older than 60 years of age
• Children younger than 5 years of age
• People with alcoholism
• People with sickle cell anemia
• People with cancer, especially those receiving chemotherapy
• People who have received transplants and are taking drugs that suppress the immune system
• People with diabetes
• Those recently exposed to meningitis at home
• People living in close quarters (military barracks, dormitories)
• IV drug users
• People with shunts in place for hydrocephalus

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

• sneezing
• coughing
• kissing
• sharing utensils, such as cutlery
• sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases).

• a boarding school
• a university campus
• a military base
• student housing

Symptoms of Meningitis

Possible signs and symptoms in anyone older than the age of 2 include

• Sudden high fever
• Severe headache that seems different than normal
• Headache with nausea or vomiting
• Confusion or difficulty concentrating
• Stiff neck occurs in a majority of people with meningitis
• Fever and chills occur in most people with meningitis
• Vomiting occurs in many of people with meningitis
• Extreme sensitivity to bright lights (photophobia)
• Confusion
• Seizures
• History of a recent upper respiratory infection (for example, cold, sore throat)
• Drowsiness
• Sleepiness or difficulty waking
• Sensitivity to light
• No appetite or thirst
• Skin rash (sometimes, such as in meningococcal meningitis)

Signs of Meningitis in newborns 

Newborns and infants may show these signs

• High fever
• Constant crying
• Be agitated and not want to be picked up
• Have a bulging soft spot on their head (fontanelle)
• Be floppy or unresponsive
• Have an unusually high-pitched cry
• Excessive sleepiness or irritability
• Inactivity or sluggishness
• Poor feeding
• A bulge in the soft spot on top of a baby’s head (fontanel)
• Stiffness in a baby’s body and neck

Diagnosis of Meningitis

Laboratory Investigations

• Initial blood tests – should be performed for full blood count, coagulation studies, and electrolytes to assess for complications of sepsis and to guide fluid management. Serum glucose should be routinely measured as it may be low in the child with meningitis, contributing to seizures. Its measurement is also needed to accurately interpret the CSF glucose.
• Blood cultures – should be performed in all patients with suspected bacterial meningitis. They may be of particular value if a lumbar puncture is contraindicated. The likelihood of a positive blood culture result varies with the infecting organism; 40% of children with meningococcal meningitis will have a positive blood culture, whereas 50–90% of H. influenzae and 75% of S. pneumonia meningitis patients will have a positive culture result [rx].
• Both CRP and procalcitonin – have been evaluated to distinguish between viral and bacterial meningitis. Several studies have shown procalcitonin to have better diagnostic accuracy than CRP in differentiating between aseptic and bacterial meningitis [rx, rx]. Procalcitonin levels in combination with other clinical scoring systems have also been studied to evaluate the risk of bacterial meningitis [rx, rx]. Although potentially increasing the sensitivity of scoring systems, the use of procalcitonin in association with clinical scores to exclude the diagnosis of bacterial meningitis is not currently recommended

Cerebrospinal fluid biochemistry

• Cerebrospinal fluid glucose is normally approximately two-thirds of the blood (plasma) concentration. It is often lower in bacterial and tuberculous meningitis. As CSF glucose is influenced by the plasma glucose, it is essential to measure blood glucose at LP, to obtain an accurate CSF – blood glucose ratio. A CSF – blood glucose ratio <0.36 is an accurate (93%) marker for distinguishing bacterial from viral meningitis.[rx]
• Cerebrospinal fluid protein is normally <0.4 g/L. Elevated protein suggests inflammation. A CSF protein < 0.6 g/L largely rules out bacterial infection.[rx]

Common Tests Include The Following

• Chest X-rays –  can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
• A CT scan  – of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
• MRI – to be oversure about meningitis

Treatment

Immediate treatment

• Antibiotics – These are usually given intravenously.
• Corticosteroids – These may be given if inflammation is causing pressure in the brain, but studies show conflicting results.
• Acetaminophen, or paracetamol –Together with cool sponge baths, cooling pads, fluids, and room ventilation, these reduce fever.
• Anticonvulsants – If the patient has seizures, an anticonvulsant, such as phenobarbital or Dilantin, may be used.
• Oxygen therapy – Oxygen will be administered to assist with breathing.
• Fluids – Intravenous fluids can prevent dehydration, especially if the patient is vomiting or cannot drink.
• Sedatives – These will calm the patient if they are irritable or restless.

Blood tests may be used to monitor the patient’s levels of blood sugar, sodium, and other vital chemicals.

Treatment / Management

Antibiotics and supportive care are critical in all infectious resuscitations.[rx][rx][rx]

Managing the airway, maintaining oxygenation, giving sufficient intra-venous fluids while providing fever control are parts of the foundation of sepsis management.

The type of antibiotic is based on the presumed organism causing the infection. The clinician must take into account patient demographics and past medical history in order to provide the best antimicrobial coverage.

Current Empiric Therapy

Neonates – Up to 1 month old

• Ampicillin 100 mg/kg intravenously (IV) and
• Cefotaxime 75 mg/kg IV or Gentamicin 2.5 mg/kg IV and
• Acyclovir IV 40 mg/kg

More than 1 month old

• Ampicillin 50 mg/kg IV and
• Ceftriaxone 2 g IV  and
• Acyclovir IV 40 mg/kg

Adults (18 to 49 years old)

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV

Adults older than 50 years old and the immunocompromised

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV and
• Ampicillin 2 g IV

Meningitis associated with a foreign body (post-procedure, penetrating trauma)

• Cefepime 2 g IV or Ceftazidime 2 g IV or Meropenem 2 g IV and
• Vancomycin 20 mg/kg IV

Meningitis with severe penicillin allergy

• Chloramphenicol 1 g IV and
• Vancomycin 20 mg/kg IV

Fungal (Cryptococcal) meningitis

• Amphotericin B 1 mg/kg IV and
• Flucytosine 25 mg/kg by mouth

Antibiotics

Ceftriaxone

• Third-generation cephalosporin
• Gram-negative coverage
• Very effective against S. pneumoniae and N. meningitides
• Better CNS penetration than Piperacillin-Tazobactam (typically used in gram-negative sepsis coverage)

Vancomycin

• Gram-positive coverage (MRSA)
• Also used for resistant pneumococcus

Ampicillin

• Listeria coverage (gram-positive bacilli)
• Is an aminopenicillin

Cefepime

• Fourth generation cephalosporin
• Increased activity against pseudomonas

Cefotaxime

• Third generation Cephalosporin
• Safe for neonates

Steroid Therapy

Administration of dexamethasone 10 mg IV before or with the first dose of antibiotics has been shown to reduce the risk of morbidity and mortality, especially in the setting of S. pneumoniae infection.

It is important to note; the Infectious Disease Society of America recommends against dexamethasone if the patient has already received antibiotics.

Increased Intracranial Pressure

If the patient develops clinical signs of increased intracranial pressure, interventions to maintain cerebral perfusion include:

• Elevating the head of the bed to 30 degrees
• Inducing mild hyperventilation in the intubated patient
• Osmotic diuretics such as 25% mannitol or 3% saline

Chemoprophylaxis

The transmission rate of N. meningitidis is 5% for close contacts, but chemoprophylaxis within 24 hours decreases that by 89%. Thus, chemoprophylaxis is indicated for close contacts of a patient suspected of having bacterial meningitis.

Close contacts include housemates, significant others, those who have shared utensils and health care providers in proximity to secretions (providing mouth-to-mouth resuscitation, intubating without a facemask).

Antibiotic chemoprophylaxis options include:

• Rifampin 10 mg/kg (max 200 mg/dose) every 12 hours for 4 doses or
• Ciprofloxacin 500 g orally once, or
• Ceftriaxone 250 mg intramuscularly once

Prevention of Meningitis

As several types of bacteria can cause bacterial meningitis, so a range of vaccines is necessary to prevent infection.

• Haemophilus influenzae type b – can be prevented with Hib immunisation, which is available in combination vaccines free on the National Immunisation Program Schedule. It is routinely offered tor babies and needs to be purchased on prescription for some groups at high risk of bacterial disease.
• Meningococcal group A, B, C, W135 and Y – can be prevented with a range of vaccines. Some immunisation is available free on the National Immunisation Program Schedule routinely for 12 month old babies or childhood catch-up and some vaccine needs to be purchased with prescription for some groups at high risk of bacterial disease or some travellers
• Pneumococcal – can be prevented with two types of pneumococcal vaccine.. They are available free on the National Immunisation Schedule to all babies and adults 50 years of age, if the person is an Aboriginal or Torres Strait Islander, or at 65 years of age and over. They need to be purchased on prescription for some groups at high risk of bacterial disease.
• A survey of 17 million people in the U.S. found that the incidence of all types of meningitis fell by 31 percent from 1998 to 2007, after the introduction of routine vaccinations against meningitis-causing bacteria.
• The meningococcal vaccine is the primary vaccine in the U.S. All children should have this at the age of 11 to 12 years and again at 16 years, when the risk of infection is higher.
• The Hib vaccine protects children against H. Influenzae. Before its introduction in the U.S. in 1985, H. Influenzae infected over 20,000 children under 5 years annually, with a 3 to 6 percent mortality rate. Widespread vaccination has reduced the incidence of bacterial meningitis by over 99 percent.
• The Hib vaccine is given in four doses at the ages of 2, 4, 6, and 12 to 15 months.

Complication

For patients treated promptly, the prognosis is good. However, patients who present with an altered state of consciousness have a high morbidity and mortality. Some patients may develop seizures during the illness, which are very difficult to control or are prolonged. Any patient with a residual neurological deficit after meningitis treatment is also left with a disability. Patients art the greatest risk for death usually have the following features:

• Advanced aged
• Low GCS
• CSF WBC count which is low
• Tachycardia
• Gram-positive cocci in the CSF

Serious complications in survivors include:

• Ataxia
• Hearing loss
• Cranial nerve palsies
• Cognitive dysfunction
• Cortical blindness
• Hydrocephalus
• Seizures
• Focal paralysis

References

[wpedon id=”117664″ align=”center”]

People Also Reading

Meningitis Treatment, Prevention, Complication Treatment of Meningitis, Treatment, Prevention Meningitis Symptoms, Diagnosis, Treatment Fungal Meningitis, Causes, Diagnosis, Treatment Meningitis; Causes, Symptoms, Diagnosis, Treatment Meningitis Causes Symptoms, Treatment Bacterial Meningitis, Causes, Symptoms, Treatment Viral Meningitis, Causes, Symptoms, Treatment Parasitic Meningitis, Symptoms, Treatment Meningitis Types, Causes, Treatment, Home Tips Child Meningitis; Causes, Symptoms, Treatment Black Eye Diagnosis, Treatment, Prevention

Meningitis Causes/Meningitis is inflammation of the meninges covering the brain. It is a pathological definition. The cerebrospinal fluid (CSF) typically exhibits an elevated number of leucocytes (or a pleocytosis). In adults, >5 leucocytes/μL is defined as elevated. Bacterial or viral meningitis is confirmed by the detection of a pathogen in the CSF. Bacterial meningitis may also be suggested by symptoms of meningism and appropriate bacteria in the blood.[rx]

Meningitis is an inflammation of the membranes (meninges) surrounding your brain and spinal cord. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

Types of Meningitis

Bacterial

Meningitis caused by bacteria can be deadly and requires immediate medical attention. Vaccines are available to help protect against some kinds of bacterial meningitis. Streptococcus pneumoniae- A causative bacteria of meningitis.

The types of bacteria that cause bacterial meningitis vary according to the infected individual’s age group.

• In premature babies and newborns up to three months old – common causes are group B streptococci (subtypes III which normally inhabit the vagina and are mainly a cause during the first week of life) and bacteria that normally inhabit the digestive tract such as Escherichia coli (carrying the K1 antigen). Listeria monocytogenes (serotype IVb) is transmitted by the mother before birth and may cause meningitis in the newborn.
• Older children are more commonly affected by – Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (serotypes 6, 9, 14, 18 and 23) and those under five by Haemophilus influenzae type B (in countries that do not offer vaccination).
• In adults –  Neisseria meningitidis and Streptococcus pneumoniae together cause 80% of bacterial meningitis cases. Risk of infection with Listeria monocytogenes is increased in persons over 50 years old. The introduction of the pneumococcal vaccine has lowered rates of pneumococcal meningitis in both children and adults.
• Recent skull trauma potentially – allows nasal cavity bacteria to enter the meningeal space. Similarly, devices in the brain and meninges, such as cerebral shunts, extraventricular drains or Ommaya reservoirs, carry an increased risk of meningitis. In these cases, the persons are more likely to be infected with Staphylococci, Pseudomonas, and other Gram-negative bacteria. These pathogens are also associated with meningitis in people with an impaired immune system.
• Tuberculous meningitis – which is meningitis caused by Mycobacterium tuberculosis, is more common in people from countries in which tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS.

Viral

• Meningitis caused by viruses is serious but often is less severe than bacterial meningitis. People with normal immune systems who get viral meningitis usually get better on their own. There are vaccines to prevent some kinds of viral meningitis.
• Viruses that cause meningitis include enteroviruses, herpes simplex virus (generally type 2, which produces most genital sores; less commonly type 1), varicella zoster virus (known for causing chickenpox and shingles), mumps virus, HIV, and LCMV. Mollaret’s meningitis is a chronic recurrent form of herpes meningitis; it is thought to be caused by herpes simplex virus type 2.

Fungal

• Meningitis caused by fungi is rare, but people can get it by inhaling fungal spores from the environment. People with certain medical conditions, like diabetes, cancer, or HIV, are at higher risk of fungal meningitis.
• There are a number of risk factors for fungal meningitis, including the use of immunosuppressants (such as after organ transplantation), HIV/AIDS, and the loss of immunity associated with aging. It is uncommon in those with a normal immune system but has occurred with medication contamination.
• Symptom onset is typically more gradual, with headaches and fever being present for at least a couple of weeks before diagnosis. The most common fungal meningitis is cryptococcal meningitis due to Cryptococcus neoformans.
• In Africa, cryptococcal meningitis is now the most common cause of meningitis in multiple studies, and it accounts for 20–25% of AIDS-related deaths in Africa. Other less common fungal pathogens which can cause meningitis include: Coccidioides immitis, Histoplasma capsulatum, Blastomyces dermatitidis, and Candidaspecies.

Parasitic

• Various parasites can cause meningitis or can affect the brain or nervous system in other ways. Overall, parasitic meningitis is much less common than viral and bacterial meningitis.
• A parasitic cause is often assumed when there is a predominance of eosinophils (a type of white blood cell) in the CSF. The most common parasites implicated are Angiostrongylus cantonensis, Gnathostoma spinigerum, Schistosoma, as well as the conditions cysticercosis, toxocariasis, baylisascariasis, paragonimiasis, and a number of rarer infections and noninfective conditions.

Aseptic meningitis

Aseptic meningitis is a term referring to the broad category of meningitis that is not caused by bacteria. Approximately 50% of aseptic meningitis is due to viral infections. Other less common causes include

• drug reactions or allergies, and
• inflammatory diseases like lupus.

Non-infectious

• Meningitis may occur as the result of several non-infectious causes: the spread of cancer to the meninges (malignant or neoplastic meningitis) and certain drugs (mainly non-steroidal anti-inflammatory drugs, antibiotics and intravenous immunoglobulins).
• It may also be caused by several inflammatory conditions, such as sarcoidosis (which is then called neurosarcoidosis), connective tissue disorders such as systemic lupus erythematosus, and certain forms of vasculitis (inflammatory conditions of the blood vessel wall), such as Behçet’s disease. Epidermoid cysts and dermoid cysts may cause meningitis by releasing irritant matter into the subarachnoid space.

Pathophysiology

Meningitis typically occurs through two routes of inoculation:

Hematogenous Seeding

• Bacterial droplets colonize the nasopharynx and enter the bloodstream after the mucosal invasion. Upon making their way to the subarachnoid space, the bacteria cross the blood-brain barrier, causing a direct inflammatory and immune-mediated reaction.

Direct Contiguous Spread

• Organisms can enter the cerebrospinal fluid (CSF) via neighboring anatomic structures (otitis media, sinusitis), foreign objects (medical devices, penetrating trauma) or during operative procedures.

Viruses can penetrate the central nervous system (CNS) via retrograde transmission along neuronal pathways or by hematogenous seeding.

Causes of Meningitis

Several strains of bacteria can cause acute bacterial meningitis, most commonly

• Streptococcus pneumoniae (pneumococcus) – This bacterium is the most common cause of bacterial meningitis in infants, young children, and adults in the United States. It more commonly causes pneumonia or ear or sinus infections. A vaccine can help prevent this infection.
• Neisseria meningitidis (meningococcus) – This bacterium is another leading cause of bacterial meningitis. These bacteria commonly cause an upper respiratory infection but can cause meningococcal meningitis when they enter the bloodstream. This is a highly contagious infection that affects mainly teenagers and young adults. It may cause local epidemics in college dormitories, boarding schools, and military bases. A vaccine can help prevent infection.
• Haemophilus influenzae (Haemophilus) – Haemophilus influenza type b (Hib) bacterium was once the leading cause of bacterial meningitis in children. But new Hib vaccines have greatly reduced the number of cases of this type of meningitis.
• Listeria monocytogenes (listeria) – These bacteria can be found in unpasteurized cheeses, hot dogs and luncheon meats. Pregnant women, newborns, older adults and people with weakened immune systems are most susceptible.
• Fungal infection
• Syphilis
• Tuberculosis
• Autoimmune disorders
• Cancer medications
• Adults older than 60 years of age
• Children younger than 5 years of age
• People with alcoholism
• People with sickle cell anemia
• People with cancer, especially those receiving chemotherapy
• People who have received transplants and are taking drugs that suppress the immune system
• People with diabetes
• Those recently exposed to meningitis at home
• People living in close quarters (military barracks, dormitories)
• IV drug users
• People with shunts in place for hydrocephalus

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

• sneezing
• coughing
• kissing
• sharing utensils, such as cutlery
• sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases).

• a boarding school
• a university campus
• a military base
• student housing

Symptoms of Meningitis

Possible signs and symptoms in anyone older than the age of 2 include

• Sudden high fever
• Severe headache that seems different than normal
• Headache with nausea or vomiting
• Confusion or difficulty concentrating
• Stiff neck occurs in a majority of people with meningitis
• Fever and chills occur in most people with meningitis
• Vomiting occurs in many of people with meningitis
• Extreme sensitivity to bright lights (photophobia)
• Confusion
• Seizures
• History of a recent upper respiratory infection (for example, cold, sore throat)
• Drowsiness
• Sleepiness or difficulty waking
• Sensitivity to light
• No appetite or thirst
• Skin rash (sometimes, such as in meningococcal meningitis)

Signs of Meningitis in newborns 

Newborns and infants may show these signs

• High fever
• Constant crying
• Be agitated and not want to be picked up
• Have a bulging soft spot on their head (fontanelle)
• Be floppy or unresponsive
• Have an unusually high-pitched cry
• Excessive sleepiness or irritability
• Inactivity or sluggishness
• Poor feeding
• A bulge in the soft spot on top of a baby’s head (fontanel)
• Stiffness in a baby’s body and neck

Diagnosis of Meningitis

Laboratory Investigations

• Initial blood tests – should be performed for full blood count, coagulation studies, and electrolytes to assess for complications of sepsis and to guide fluid management. Serum glucose should be routinely measured as it may be low in the child with meningitis, contributing to seizures. Its measurement is also needed to accurately interpret the CSF glucose.
• Blood cultures – should be performed in all patients with suspected bacterial meningitis. They may be of particular value if a lumbar puncture is contraindicated. The likelihood of a positive blood culture result varies with the infecting organism; 40% of children with meningococcal meningitis will have a positive blood culture, whereas 50–90% of H. influenzae and 75% of S. pneumonia meningitis patients will have a positive culture result [rx].
• Both CRP and procalcitonin – have been evaluated to distinguish between viral and bacterial meningitis. Several studies have shown procalcitonin to have better diagnostic accuracy than CRP in differentiating between aseptic and bacterial meningitis [rx, rx]. Procalcitonin levels in combination with other clinical scoring systems have also been studied to evaluate the risk of bacterial meningitis [rx, rx]. Although potentially increasing the sensitivity of scoring systems, the use of procalcitonin in association with clinical scores to exclude the diagnosis of bacterial meningitis is not currently recommended

Cerebrospinal fluid biochemistry

• Cerebrospinal fluid glucose is normally approximately two-thirds of the blood (plasma) concentration. It is often lower in bacterial and tuberculous meningitis. As CSF glucose is influenced by the plasma glucose, it is essential to measure blood glucose at LP, to obtain an accurate CSF – blood glucose ratio. A CSF – blood glucose ratio <0.36 is an accurate (93%) marker for distinguishing bacterial from viral meningitis.[rx]
• Cerebrospinal fluid protein is normally <0.4 g/L. Elevated protein suggests inflammation. A CSF protein < 0.6 g/L largely rules out bacterial infection.[rx]

Common Tests Include The Following

• Chest X-rays –  can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
• A CT scan  – of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
• MRI – to be oversure about meningitis

Treatment

Immediate treatment

• Antibiotics – These are usually given intravenously.
• Corticosteroids – These may be given if inflammation is causing pressure in the brain, but studies show conflicting results.
• Acetaminophen, or paracetamol –Together with cool sponge baths, cooling pads, fluids, and room ventilation, these reduce fever.
• Anticonvulsants – If the patient has seizures, an anticonvulsant, such as phenobarbital or Dilantin, may be used.
• Oxygen therapy – Oxygen will be administered to assist with breathing.
• Fluids – Intravenous fluids can prevent dehydration, especially if the patient is vomiting or cannot drink.
• Sedatives – These will calm the patient if they are irritable or restless.

Blood tests may be used to monitor the patient’s levels of blood sugar, sodium, and other vital chemicals.

Treatment / Management

Antibiotics and supportive care are critical in all infectious resuscitations.[rx][rx][rx]

Managing the airway, maintaining oxygenation, giving sufficient intra-venous fluids while providing fever control are parts of the foundation of sepsis management.

The type of antibiotic is based on the presumed organism causing the infection. The clinician must take into account patient demographics and past medical history in order to provide the best antimicrobial coverage.

Current Empiric Therapy

Neonates – Up to 1 month old

• Ampicillin 100 mg/kg intravenously (IV) and
• Cefotaxime 75 mg/kg IV or Gentamicin 2.5 mg/kg IV and
• Acyclovir IV 40 mg/kg

More than 1 month old

• Ampicillin 50 mg/kg IV and
• Ceftriaxone 2 g IV  and
• Acyclovir IV 40 mg/kg

Adults (18 to 49 years old)

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV

Adults older than 50 years old and the immunocompromised

• Ceftriaxone 2 g IV and
• Vancomycin 20 mg/kg IV and
• Ampicillin 2 g IV

Meningitis associated with a foreign body (post-procedure, penetrating trauma)

• Cefepime 2 g IV or Ceftazidime 2 g IV or Meropenem 2 g IV and
• Vancomycin 20 mg/kg IV

Meningitis with severe penicillin allergy

• Chloramphenicol 1 g IV and
• Vancomycin 20 mg/kg IV

Fungal (Cryptococcal) meningitis

• Amphotericin B 1 mg/kg IV and
• Flucytosine 25 mg/kg by mouth

Antibiotics

Ceftriaxone

• Third-generation cephalosporin
• Gram-negative coverage
• Very effective against S. pneumoniae and N. meningitides
• Better CNS penetration than Piperacillin-Tazobactam (typically used in gram-negative sepsis coverage)

Vancomycin

• Gram-positive coverage (MRSA)
• Also used for resistant pneumococcus

Ampicillin

• Listeria coverage (gram-positive bacilli)
• Is an aminopenicillin

Cefepime

• Fourth generation cephalosporin
• Increased activity against pseudomonas

Cefotaxime

• Third generation Cephalosporin
• Safe for neonates

Steroid Therapy

Administration of dexamethasone 10 mg IV before or with the first dose of antibiotics has been shown to reduce the risk of morbidity and mortality, especially in the setting of S. pneumoniae infection.

It is important to note; the Infectious Disease Society of America recommends against dexamethasone if the patient has already received antibiotics.

Increased Intracranial Pressure

If the patient develops clinical signs of increased intracranial pressure, interventions to maintain cerebral perfusion include:

• Elevating the head of the bed to 30 degrees
• Inducing mild hyperventilation in the intubated patient
• Osmotic diuretics such as 25% mannitol or 3% saline

Chemoprophylaxis

The transmission rate of N. meningitidis is 5% for close contacts, but chemoprophylaxis within 24 hours decreases that by 89%. Thus, chemoprophylaxis is indicated for close contacts of a patient suspected of having bacterial meningitis.

Close contacts include housemates, significant others, those who have shared utensils and health care providers in proximity to secretions (providing mouth-to-mouth resuscitation, intubating without a facemask).

Antibiotic chemoprophylaxis options include:

• Rifampin 10 mg/kg (max 200 mg/dose) every 12 hours for 4 doses or
• Ciprofloxacin 500 g orally once, or
• Ceftriaxone 250 mg intramuscularly once

Prevention of Meningitis

As several types of bacteria can cause bacterial meningitis, so a range of vaccines is necessary to prevent infection.

• Haemophilus influenzae type b – can be prevented with Hib immunisation, which is available in combination vaccines free on the National Immunisation Program Schedule. It is routinely offered tor babies and needs to be purchased on prescription for some groups at high risk of bacterial disease.
• Meningococcal group A, B, C, W135 and Y – can be prevented with a range of vaccines. Some immunisation is available free on the National Immunisation Program Schedule routinely for 12 month old babies or childhood catch-up and some vaccine needs to be purchased with prescription for some groups at high risk of bacterial disease or some travellers
• Pneumococcal – can be prevented with two types of pneumococcal vaccine.. They are available free on the National Immunisation Schedule to all babies and adults 50 years of age, if the person is an Aboriginal or Torres Strait Islander, or at 65 years of age and over. They need to be purchased on prescription for some groups at high risk of bacterial disease.
• A survey of 17 million people in the U.S. found that the incidence of all types of meningitis fell by 31 percent from 1998 to 2007, after the introduction of routine vaccinations against meningitis-causing bacteria.
• The meningococcal vaccine is the primary vaccine in the U.S. All children should have this at the age of 11 to 12 years and again at 16 years, when the risk of infection is higher.
• The Hib vaccine protects children against H. Influenzae. Before its introduction in the U.S. in 1985, H. Influenzae infected over 20,000 children under 5 years annually, with a 3 to 6 percent mortality rate. Widespread vaccination has reduced the incidence of bacterial meningitis by over 99 percent.
• The Hib vaccine is given in four doses at the ages of 2, 4, 6, and 12 to 15 months.

Complication

For patients treated promptly, the prognosis is good. However, patients who present with an altered state of consciousness have a high morbidity and mortality. Some patients may develop seizures during the illness, which are very difficult to control or are prolonged. Any patient with a residual neurological deficit after meningitis treatment is also left with a disability. Patients art the greatest risk for death usually have the following features:

• Advanced aged
• Low GCS
• CSF WBC count which is low
• Tachycardia
• Gram-positive cocci in the CSF

Serious complications in survivors include:

• Ataxia
• Hearing loss
• Cranial nerve palsies
• Cognitive dysfunction
• Cortical blindness
• Hydrocephalus
• Seizures
• Focal paralysis

References

[wpedon id=”117664″ align=”center”]

People Also Reading

Bacterial Meningitis, Causes, Symptoms, Treatment Meningitis Symptoms, Diagnosis, Treatment Viral Meningitis, Causes, Symptoms, Treatment Parasitic Meningitis, Symptoms, Treatment Child Meningitis; Causes, Symptoms, Treatment Meningitis; Causes, Symptoms, Diagnosis, Treatment Meningitis Diagnosis, Treatment, Prevention Meningitis Treatment, Prevention, Complication Fungal Meningitis, Causes, Diagnosis, Treatment Meningitis Types, Causes, Treatment, Home Tips Treatment of Meningitis, Treatment, Prevention What is meningitis? What is encephalitis?

Phantom Pain Treatment/Phantom Pain is clinically defined as the perception of pain or discomfort in a limb that no longer exists.  Although PLP most commonly presents as pathological sequelae in amputee patients, the underlying pathophysiology remains poorly understood. PLP can present along a wide clinical spectrum and varying severity of symptoms.  The condition should be differentiated from other related but separate clinical conditions, including residual limb pain (RLP).  RLP (formerly known as “stump pain”) is pain that originates from the actual site of the amputated limb.  It is most common in the early post-amputation period and tends to resolve with wound healing. Unlike PLP, RLP is often a manifestation of an underlying source, such as nerve entrapment, neuroma formation, surgical trauma, ischemia, skin breakdown, or infection.[rx]

Phantom pain is a perception that an individual experience relating to a limb or an organ that is not physically part of the body. Limb loss is a result of either removal by amputation or congenital limb deficiency.^[rx] However, phantom limb sensations can also occur following nerve avulsion or spinal cord injury.

Mechanisms Phantom Pain

The mechanism responsible for PLP and PLS is still debatable, however, a lot of theories had been given. Following amputation, there may be the formation of neuroma showing abnormal spontaneous activity, and on mechanical and chemical stimulation, which is thought to be due to upregulation of sodium channels. Furthermore, other factors thought to have an influence on the PLP are decreased threshold for PLP, increased c-fiber activity, inverse relationship between pressure pain threshold and phantom limb pain intensity, abnormal activity of dorsal root ganglion, and so on.[rx,rx] The sympathetic nervous system also plays a role in maintaining PLP.[rx,rx] Further, there is spinal plasticity, i.e., increase in the excitability of spinal neurons, more accessibility of Aδ- and c-fibers to other pathways.[rx] N-methyl-D-aspartate receptor systems are also believed to have a role in the “wind-up” phenomenon seen in PLP.[rx] Furthermore, spinal and cerebral reorganization occurs and there is a relationship between the degree of reorganization and pain.[rx,rx]

Types of Phantom Pain

There are various types of sensations that may be felt:

• Sensations related to the phantom limb’s posture –  length and volume e.g. feeling that the phantom limb is behaving just like a normal limb like sitting with the knee bent or feeling that the phantom limb is as heavy as the other limb. Sometimes, an amputee will experience a sensation called telescoping. This is the feeling that the phantom limb is gradually shortening over time.
• Sensations of movement – (e.g. feeling that the phantom foot is moving).
• Sensations of touch, temperature – pressure and itchiness. Many amputees report of feeling heat, tingling, itchiness, and pain.

Causes of Phantom Pain

• Peripheral Nerve Changes – During the amputation, there is a significant amount of trauma that occurs in the nerves and surrounding tissues. This damage disrupts the normal afferent and efferent signals involved with the missing limb. The proximal portions of the severed nerves start to sprout neuromas, and the nerves become hyper-excitable due to an increase in sodium-channels and resulting in spontaneous discharges. [rx]
• Spinal Cord Changes – In the spinal cord, a process called central sensitization occurs. Central sensitization is a process where neural activity increases, the neuronal receptive field expands, and the nerves become hypersensitive. This is due to an increase in the N-methyl-D-aspartate, or NMDA, activity in the dorsal horn of the spinal cord making them more susceptible to activation by substance P, tachykinins, and neurokinins followed by an upregulation of the receptors in that area. This restructuring of the neural components of the spinal cord can cause the descending inhibitory fibers to lose their target sites. The combination of increased activity to nociceptive signals as well as a decrease in the inhibitory activity from the supraspinal centers is thought to be one of the major contributors to phantom limb pain. [rx]
• Brain Changes – Over the past few years, there has been significant research into cortical reorganization and is a commonly cited factor in phantom limb pain.  During this process, the areas of the cortex that represent the amputated area are taken over by the neighboring regions in both the primary somatosensory and the motor cortex. Cortical reorganization partially explains why nociceptive stimulation of the nerves in the residual limb and surrounding area can cause pain and sensation in the missing limb. There is also a correlation between the extent of cortical reorganization and the amount of pain that the patient feels. [rx]
• Psychogenic Factors – Chronic pain has been shown to be multi-factorial with a strong psychological component. Phantom limb pain can often develop into chronic pain syndrome and for treatment to have a higher chance of success the patient’s pain behaviors and pain processing should be addressed. Depression, anxiety, and increased stress are all triggers for phantom limb pain. [rx] As with any other kind of pain, you may find that certain activities or conditions will trigger PLP. Some of these triggers might include-
• Touch
• Urination or defecation
• Sexual intercourse
• Angina
• Cigarette smoking
• Changes in barometric pressure
• Herpes zoster
• Exposure to cold.

Symptoms of Phantom Pain

It onset within the first few days of amputation. Comes and goes or is continuous. Often affects the part of the limb farthest from the body, such as the foot of an amputated leg. May be described as a shooting, stabbing, boring, squeezing, throbbing or burning. Sometimes feels as if the phantom part is forced into an uncomfortable position. May be triggered by pressure on the remaining part of the limb or emotional stress.^[rx]

• Onset within the first week after amputation, though it can be delayed by months or longer
• Pain that comes and goes or is continuous
• Symptoms affecting the part of the limb farthest from the body, such as the foot of an amputated leg
• Pain that may be described as shooting, stabbing, cramping, pins and needles, crushing, throbbing, or burning

Phantom limb sensation – is a nonpainful feeling or sensation in the body part that was amputated. Phantom sensations are more commonly reported than stump pain or phantom limb pain. The sensations feel like the limb felt before the amputation, and are related to the same sense of awareness that helps people distinguish “myself” from others. The sensations occur from the interaction of current sensory inputs from your limb, and the internal “models” of the body in the brain.

• Early on, the phantom limb resembles the limb shape prior to amputation. It may be perceived in a certain position, have feelings of warmth or cold, itching, or tingling.
• Following amputation, it is common to “forget” the limb is absent and to attempt to use it—a sensation that can result in a fall.
• It is also common for people who experienced amputation to feel as though the upper portion of the limb is missing, or has shrunk. This phenomenon, called telescoping, is caused by a change in the internal model of the body in the brain. It also can cause the sensation that the amputated part of the limb is floating, or has even moved up inside the stump.

Stump pain is common in the postoperative period. It is felt only in the remaining body part, or stump. Stump pain may be felt at the incision or deeper into the residual limb. This pain is often described as sharp, burning, stabbing, or “electric.” Stump pain, which normally fades as the surgical scar heals, can coexist with phantom limb pain.

Phantom limb pain is a painful or unpleasant sensation in the lost body part. Sensations can include:

• Tingling, burning, and cramping (the most common pain felt from amputation)
• Shooting, stabbing, boring, squeezing, or throbbing pain
• Pain just like that experienced at the time of the accident or serious injury
• A feeling like the phantom limb is in a forced and uncomfortable position

Since phantom pain is related to the brain and nervous system, it can also be experienced in the nonamputated part of the limb, in the opposite nonamputated limb, or even in the neck or back. Phantom limb pain usually affects the part of the limb farthest from the body. For example, lower-limb phantom pain will usually be experienced in the toes, heel, instep, or top of the foot. The pain may be continuous, or it may come and go during the day. In many cases, it occurs randomly.

Phantom pain may be triggered by

• Pressure on the remaining part of the limb from objects such as clothing
• Emotional stress
• Forgetting the limb’s absence and attempting to use it
• A poorly fitting artificial limb
• Stump pain

Diagnosis of Phantom Limb Pain

There are no medical tests to diagnose phantom limb pain. Diagnosis is made based on your symptoms and the history of what occurred before the pain started. For example, was there illness, trauma, or surgery before the amputation? Reporting clearly and precisely what seems to trigger the phantom pain will help your physical therapist diagnose the problem. The physical therapist may have you complete questionnaires about your symptoms and functional difficulties to help clarify details of your problem and how it is affecting your daily life and activities. All other possible sources of your pain symptoms must be ruled out.

Your physical therapist will

• Perform a careful examination of the bone and soft tissues of your stump to identify possible skin breakdown, infection, or abnormal pressure on weight-bearing contact points.
• Gently tap on the stump to identify possible nerve injury or a neuroma (an overgrowth of nerves in the stump).
• Check the fit of your prosthetic limb. (It is common for the shape of your stump to change over time, affecting the prosthetic’s fit and comfort.)
• Check to make sure that you are using the correct stump socks, and that you are putting your prosthetic on properly.
• Explain how any of the above changes can cause skin breakdown and provoke pain problems.

Your physical therapist will work with your physician to determine the need for additional tests to rule out other conditions, such as poor circulation, and may refer you for X-rays to identify bone spurs or other abnormal bone formations.

Treatment of Phantom Pain

Pharmacotherapy

• NSAIDs/Tylenol – are the most commonly used treatment for phantom limb pain. The mechanism of action is unknown.[rx]
• Opioids – Randomized controlled trials have demonstrated the effectiveness of opioids for neuropathic pain and phantom limb pain. Drugs such as codeine and morphine may ease phantom limb pain for some people, but not everyone. Tell your doctor if you have a history of substance abuse before you take one of these drugs. Should be used in conjunction with antidepressants or neural modulating agents (i.e., gabapentin, pregabalin). [rx]
• Antidepressants – are commonly used for phantom limb pain. Amitryptiline, in particular, is the TCA of choice as it has shown good results, but other studies looking at Nortryptyline and desipramine have shown them to be equally effective. Duloxetine is another medication that has been showing some positive results. [rx]
• Anticonvulsants (Gabapentin, Pregabalin) – have shown mixed results. [rx] These drugs treat seizures, but some can also help with nerve pain. Examples include carbamazepine (Carbatrol, Epitol, Tegretol), gabapentin(Gralise, Neurontin), and pregabalin (Lyrica).
• Calcitonin  – The mechanism of action of calcitonin in treatment of PLP is not clear. Studies relative to its therapeutic role have been mixed [rx, rx].
• NMDA Receptor antagonist–  mechanism is not clear. Memantine has had mixed results.
• Beta-blockers (propranolol) – and calcium channel blocker (nifedipine) show unclear data. A sympathetic block may also help.
• Botulinum toxin type B injections – have been used to treat hyperhidrosis (excessive sweating) in the post-amputation patient.  Hyperhidrosis can not only hinder the use of a prosthetic but can adversely affect the course of phantom limb and residual limb pain. Treatment of the hyperhidrosis with botulinum toxin type B injections has shown in several small studies to reduce residual limb pain, phantom limb pain, and sweating. [rx]  Botulinum toxin type A is also being investigated, but so far has not been shown to decrease pain intensity compared to lidocaine/methylprednisolone. [rx]
• Capsaicin – have been shown in some small studies to reduce hypersensitivity and phantom limb pain, but the evidence is still weak and requires more investigation. [rx][rx]
• Tricyclic antidepressants – Drugs such as amitriptyline (Elavil), nortriptyline(Pamelor), and tramadol (Conzip, Ultram) can ease nerve pain by changing chemicals in your body that send pain signals.
• Biofeedback, Integrative, and Behavioral Methods – Although there are earlier reports suggesting temperature biofeedback to be helpful for burning sensation of PLP, there is no specific evidence to match specific types of PLP with specific biofeedback techniques [rx]. There is also a case report of visual feedback helpful in reduction of phantom pain [rx].

Other painkillers – A few other types may help with phantom limb pain, including:

• NMDA receptor antagonists, such asketamine and dextromethorphan
• Over-the-counter medicine, such as aspirin and acetaminophen
• A shot of a pain-blocking drug in the area where you got the amputation

References

People Also Reading

Phantom Pain Causes, Symptoms, Treatment Phantom Pain Symptoms, Diagnosis, Treatment Phantom Limb Pain, Causes, Symptoms, Diagnosis, Treatment Phantom Limb Pain Causes, Symptoms, Treatment Phantom Pain, Causes, Symptoms, Diagnosis, Treatment Phantom Limb Pain Symptoms, Diagnosis, Treatment Phantom Limb Pain Treatment, Types, Complication Phantom Limb Pain Diagnosis, Treatment, Complication Phantom Leg Syndrome Treatment, Causes, Symptoms What Does Phantom Pain/ Sensation Feel Like Phantom Leg Syndrome, Causes, Symptoms, Treatment Amputation Causes, Symptoms, Treatment, Rehabilitation

Phantom Pain Causes/Phantom Pain is clinically defined as the perception of pain or discomfort in a limb that no longer exists.  Although PLP most commonly presents as a pathological sequelae in amputee patients, the underlying pathophysiology remains poorly understood. PLP can present along a wide clinical spectrum and varying severity of symptoms.  The condition should be differentiated from other related but separate clinical conditions, including residual limb pain (RLP).  RLP (formerly known as “stump pain”) is pain that originates from the actual site of the amputated limb.  It is most common in the early post-amputation period and tends to resolve with wound healing. Unlike PLP, RLP is often a manifestation of an underlying source, such as nerve entrapment, neuroma formation, surgical trauma, ischemia, skin breakdown, or infection.[rx]

Phantom pain is a perception that an individual experiences relating to a limb or an organ that is not physically part of the body. Limb loss is a result of either removal by amputation or congenital limb deficiency.^[rx] However, phantom limb sensations can also occur following nerve avulsion or spinal cord injury.

Mechanisms Phantom Pain

The mechanism responsible for PLP and PLS is still debatable, however a lot of theories had been given. Following amputation, there may be formation of neuroma showing abnormal spontaneous activity, and on mechanical and chemical stimulation, which is thought to be due to upregulation of sodium channels. Furthermore, other factors though to have an influence on the PLP are decreased threshold for PLP, increased c-fiber activity, inverse relationship between pressure pain threshold and phantom limb pain intensity, abnormal activity of dorsal root ganglion, and so on.[rx,rx] Sympathetic nervous system also plays a role in maintaining PLP.[rx,rx] Further, there is spinal plasticity, i.e., increase in the excitability of spinal neurons, more accessibility of Aδ- and c-fibers to other pathways.[rx] N-methyl-D-aspartate receptor systems are also believed to have a role in “wind-up” phenomenon seen in PLP.[rx] Furthermore, spinal and cerebral reorganization occurs and there is a relationship between degree of reorganization and pain.[rx,rx]

Types of Phantom Pain

There are various types of sensations that may be felt:

• Sensations related to the phantom limb’s posture –  length and volume e.g. feeling that the phantom limb is behaving just like a normal limb like sitting with the knee bent or feeling that the phantom limb is as heavy as the other limb. Sometimes, an amputee will experience a sensation called telescoping. This is the feeling that the phantom limb is gradually shortening over time.
• Sensations of movement – (e.g. feeling that the phantom foot is moving).
• Sensations of touch, temperature – pressure and itchiness. Many amputees report of feeling heat, tingling, itchiness, and pain.

Causes of Phantom Pain

• Peripheral Nerve Changes – During the amputation, there is a significant amount of trauma that occurs in the nerves and surrounding tissues. This damage disrupts the normal afferent and efferent signals involved with the missing limb. The proximal portions of the severed nerves start to sprout neuromas, and the nerves become hyper-excitable due to an increase in sodium-channels and resulting spontaneous discharges. [rx]
• Spinal Cord Changes – In the spinal cord, a process called central sensitization occurs. Central sensitization is a process where neural activity increases, the neuronal receptive field expands, and the nerves become hypersensitive. This is due to an increase in the N-methyl-D-aspartate, or NMDA, activity in the dorsal horn of the spinal cord making them more susceptible to activation by substance P, tachykinins, and neurokinins followed by an upregulation of the receptors in that area. This restructuring of the neural components of the spinal cord can cause the descending inhibitory fibers to lose their target sites. The combination of increased activity to nociceptive signals as well as a decrease in the inhibitory activity from the supraspinal centers is thought to be one of the major contributors to phantom limb pain. [rx]
• Brain Changes – Over the past few years, there has been significant research into cortical reorganization and is a commonly cited factor in phantom limb pain.  During this process, the areas of the cortex that represent the amputated area are taken over by the neighboring regions in both the primary somatosensory and the motor cortex. Cortical reorganization partially explains why nociceptive stimulation of the nerves in the residual limb and surrounding area can cause pain and sensation in the missing limb. There is also a correlation between the extent of cortical reorganization and the amount of pain that the patient feels. [rx]
• Psychogenic Factors – Chronic pain has been shown to be multi-factorial with a strong psychological component. Phantom limb pain can often develop into chronic pain syndrome and for treatment to have a higher chance of success the patient’s pain behaviors and pain processing should be addressed. Depression, anxiety, and increased stress are all triggers for phantom limb pain. [rx] As with any other kind of pain, you may find that certain activities or conditions will trigger PLP. Some of these triggers might include-
• Touch
• Urination or defecation
• Sexual intercourse
• Angina
• Cigarette smoking
• Changes in barometric pressure
• Herpes zoster
• Exposure to cold.

Symptoms of Phantom Pain

It onset within the first few days of amputation. Comes and goes or is continuous. Often affects the part of the limb farthest from the body, such as the foot of an amputated leg. May be described as shooting, stabbing, boring, squeezing, throbbing or burning. Sometimes feels as if the phantom part is forced into an uncomfortable position. May be triggered by pressure on the remaining part of the limb or emotional stress.^[rx]

• Onset within the first week after amputation, though it can be delayed by months or longer
• Pain that comes and goes or is continuous
• Symptoms affecting the part of the limb farthest from the body, such as the foot of an amputated leg
• Pain that may be described as shooting, stabbing, cramping, pins and needles, crushing, throbbing, or burning

Phantom limb sensation – is a nonpainful feeling or sensation in the body part that was amputated. Phantom sensations are more commonly reported than stump pain or phantom limb pain. The sensations feel like the limb felt before the amputation, and are related to the same sense of awareness that helps people distinguish “myself” from others. The sensations occur from the interaction of current sensory inputs from your limb, and the internal “models” of the body in the brain.

• Early on, the phantom limb resembles the limb shape prior to amputation. It may be perceived in a certain position, have feelings of warmth or cold, itching, or tingling.
• Following amputation, it is common to “forget” the limb is absent and to attempt to use it—a sensation that can result in a fall.
• It is also common for people who experienced amputation to feel as though the upper portion of the limb is missing, or has shrunk. This phenomenon, called telescoping, is caused by a change in the internal model of the body in the brain. It also can cause the sensation that the amputated part of the limb is floating, or has even moved up inside the stump.

Stump pain is common in the postoperative period. It is felt only in the remaining body part, or stump. Stump pain may be felt at the incision or deeper into the residual limb. This pain is often described as sharp, burning, stabbing, or “electric.” Stump pain, which normally fades as the surgical scar heals, can coexist with phantom limb pain.

Phantom limb pain is a painful or unpleasant sensation in the lost body part. Sensations can include:

• Tingling, burning, and cramping (the most common pain felt from amputation)
• Shooting, stabbing, boring, squeezing, or throbbing pain
• Pain just like that experienced at the time of the accident or serious injury
• A feeling like the phantom limb is in a forced and uncomfortable position

Since phantom pain is related to the brain and nervous system, it can also be experienced in the nonamputated part of the limb, in the opposite nonamputated limb, or even in the neck or back. Phantom limb pain usually affects the part of the limb farthest from the body. For example, lower-limb phantom pain will usually be experienced in the toes, heel, instep, or top of the foot. The pain may be continuous, or it may come and go during the day. In many cases it occurs randomly.

Phantom pain may be triggered by

• Pressure on the remaining part of the limb from objects such as clothing
• Emotional stress
• Forgetting the limb’s absence and attempting to use it
• A poorly fitting artificial limb
• Stump pain

Diagnosis of Phantom Limb Pain

There are no medical tests to diagnose phantom limb pain. Diagnosis is made based on your symptoms and the history of what occurred before the pain started. For example, was there illness, trauma, or surgery before the amputation? Reporting clearly and precisely what seems to trigger the phantom pain will help your physical therapist diagnose the problem. The physical therapist may have you complete questionnaires about your symptoms and functional difficulties to help clarify details of your problem and how it is affecting your daily life and activities. All other possible sources of your pain symptoms must be ruled out.

Your physical therapist will

• Perform a careful examination of the bone and soft tissues of your stump to identify possible skin breakdown, infection, or abnormal pressure on weight-bearing contact points.
• Gently tap on the stump to identify possible nerve injury or a neuroma (an overgrowth of nerves in the stump).
• Check the fit of your prosthetic limb. (It is common for the shape of your stump to change over time, affecting the prosthetic’s fit and comfort.)
• Check to make sure that you are using the correct stump socks, and that you are putting your prosthetic on properly.
• Explain how any of the above changes can cause skin breakdown and provoke pain problems.

Your physical therapist will work with your physician to determine the need for additional tests to rule out other conditions, such as poor circulation, and may refer you for X-rays to identify bone spurs or other abnormal bone formations.

Treatment of Phantom Pain

Pharmacotherapy

• NSAIDs/Tylenol – are the most commonly used treatment for phantom limb pain. The mechanism of action is unknown.[rx]
• Opioids – Randomized controlled trials have demonstrated the effectiveness of opioids for neuropathic pain and phantom limb pain. Drugs such as codeine and morphine may ease phantom limb pain for some people, but not everyone. Tell your doctor if you have a history of substance abuse before you take one of these drugs. Should be used in conjunction with antidepressants or neural modulating agents (i.e., gabapentin, pregabalin). [rx]
• Antidepressants – are commonly used for phantom limb pain. Amitryptiline, in particular, is the TCA of choice as it has shown good results, but other studies looking at Nortryptyline and desipramine have shown them to be equally effective. Duloxetine is another medication that has been showing some positive results. [rx]
• Anticonvulsants (Gabapentin, Pregabalin) – have shown mixed results. [rx] These drugs treat seizures, but some can also help with nerve pain. Examples include carbamazepine (Carbatrol, Epitol, Tegretol), gabapentin(Gralise, Neurontin), and pregabalin (Lyrica).
• Calcitonin  – The mechanism of action of calcitonin in treatment of PLP is not clear. Studies relative to its therapeutic role have been mixed [rx, rx].
• NMDA Receptor antagonist–  mechanism is not clear. Memantine has had mixed results.
• Beta-blockers (propranolol) – and calcium channel blocker (nifedipine) show unclear data. A sympathetic block may also help.
• Botulinum toxin type B injections – have been used to treat hyperhidrosis (excessive sweating) in the post-amputation patient.  Hyperhidrosis can not only hinder the use of a prosthetic but can adversely affect the course of phantom limb and residual limb pain. Treatment of the hyperhidrosis with botulinum toxin type B injections has shown in several small studies to reduce residual limb pain, phantom limb pain, and sweating. [rx]  Botulinum toxin type A is also being investigated, but so far has not been shown to decrease pain intensity compared to lidocaine/methylprednisolone. [rx]
• Capsaicin – have been shown in some small studies to reduce hypersensitivity and phantom limb pain, but the evidence is still weak and requires more investigation. [rx][rx]
• Tricyclic antidepressants – Drugs such as amitriptyline (Elavil), nortriptyline(Pamelor), and tramadol (Conzip, Ultram) can ease nerve pain by changing chemicals in your body that send pain signals.
• Biofeedback, Integrative, and Behavioral Methods – Although there are earlier reports suggesting temperature biofeedback to be helpful for burning sensation of PLP, there is no specific evidence to match specific types of PLP with specific biofeedback techniques [rx]. There is also a case report of visual feedback helpful in reduction of phantom pain [rx].

Other painkillers – A few other types may help with phantom limb pain, including:

• NMDA receptor antagonists, such asketamine and dextromethorphan
• Over-the-counter medicine, such as aspirin and acetaminophen
• A shot of a pain-blocking drug in the area where you got the amputation