Category Archive Neurology

Charlie horse is a popular colloquial term used for painful involuntary spasms or cramps in the leg muscles, typically lasting anywhere from a few seconds to about a day. It is a sudden and involuntary contraction of one or more of your muscles. If you’ve ever been awakened in the night or stopped in your tracks by a sudden charley horse, you know that muscle cramps can cause severe pain.

Painful involuntary skeletal muscle contractions, or cramps, are common patient complaints and may be classified as examples of true cramp, tetany, contracture, or dystonia. The pathophysiologic and clinical features of each of these diagnoses are described. The approach to the patient with cramps should emphasize the history, physical examination, and, if the diagnosis is unclear, minimal routine laboratory data. Although many therapies have been proposed for ordinary cramps, the best evidence supports stretching exercises and quinine. Areas for future study of this common symptom are proposed.

Muscle cramps are a common problem characterized by a sudden, painful, involuntary contraction of the muscle. These true cramps, which originate from peripheral nerves, may be distinguished from other muscle pain or spasm. Medical history, physical examination, and a limited laboratory screen help to determine the various causes of muscle cramps. Despite the “benign” nature of cramps, many patients find the symptom very uncomfortable. Treatment options are guided both by experience and by a limited number of therapeutic trials. Quinine sulfate is an effective medication, but the side-effect profile is worrisome, and other membrane-stabilizing drugs are probably just as effective. Patients will benefit from further studies to better define the pathophysiology of muscle cramps and to find more effective medications with fewer side-effects.

A muscle  cramp is a sudden, involuntary muscle contraction or over-shortening; while generally temporary and non-damaging, they can cause mild-to-excruciating pain, and a paralysis-like immobility of the affected muscle(s). Onset is usually sudden, and it resolves on its own over a period of several seconds, minutes, or hours. Cramps may occur in a skeletal muscle or smooth muscle. Skeletal muscle cramps may be caused by muscle fatigue or a lack of electrolytes (e.g., low sodium, low potassium, or low magnesium, although the evidence has been mixed). Cramps of smooth muscle may be due to menstruation or gastroenteritis.

Types of Charley Horse

 Praphysiologic muscle cramps

Paraphysiologic muscle cramps are commonly experienced, but they have no underlying medical condition. This includes cramps associated with:

• Pregnancy – Up to 30% of pregnant women will experience leg cramps during their pregnancy, most frequently during the last trimester;
• Exercise-The cause of exercise-associated muscle cramps (EAMC) is still largely unknown. It is believed to be highly related to physiological stress such as

Most people at some time of their life will experience an idiopathic muscle cramp. These cramps usually occur at night in the leg and foot muscles and can be triggered by even the slightest shortening of skeletal muscle.

Idiopathic muscle cramps can be classified into the following

• Nocturnal cramps – Cramps that occur at night when in bed;
• Autosomal dominant cramping disease – An inherited disease involving recurrent muscle cramping;
• Continuous muscle fiber activity syndromes – Including Isaac’s syndrome, Stiff-man syndrome and cramp fasciculation syndrome (the uncontrollable twitching of muscles beneath the skin);
• Sathoyoshi’s syndrome – Syndrome of progressive muscle spasm which includes diarrhea and alopecia;
• Myokymia – Spontaneous muscle quivering;
• Myokymia-hyperhidrosis syndrome – Myokymia paired with excessive perspiration;
• Familial insulin resistance with acanthocytosis (spiky red blood cells) and acral hypertrophy – A rare syndrome characterized by enlarged hands and feet, velvety skin and muscle cramps;
• Cancer-induced cramps 
• Natural muscle atrophy – (muscle wasting): that occurs in people over 65 predisposes them to muscle cramps. 

Symptomatic Charley Horse

Symptomatic muscle cramps constitute the majority of muscle cramps and are related to underlying disease in a number of different body systems.

Central and peripheral nervous system

• Motor neuron disease including amyotrophic lateral scoliosis;
• Parkinson’s disease;
• Multiple sclerosis (MS);
• Tetanus (lockjaw);
• Radiculopathy; and
• Peripheral neuropathies.

Muscular system

• Some myopathies (diseases that affect skeletal muscles); and
• Myotonia (temporary muscle stiffness or contraction).

Cardiovascular system

• Venous disease (disease of the veins);
• Peripheral arterial disease (arteriosclerosis); and
• Hypertension (high blood pressure).

Diseases of the endocrine-metabolic system

• Hypothyroidism (under-activity of the thyroid gland) and hyperthyroidism (over-activity of the thyroid gland);
• Hyperparathyroidism (disease of the parathyroid gland); and
• Deficiency of corticotropin (a hormone secreted by the pituitary gland).

Muscle cramps are also associated with

• Liver cirrhosis and other liver dysfunction;
• Bartter syndrome (disorder defect in the loop of Henle of the kidney);
• Gitelman’s syndrome (an inherited defect in the distal convoluted tubule of the kidney);
• Conn’s syndrome (disease of the adrenal gland);
• Addison’s disease (disease of the adrenal gland);
• Uraemia (an illness that accompanies kidney failure) and dialysis;
• Heat cramps (cramps due to dehydration and electrolyte depletion);
• Toxic.

Risk Factors for Charley Horse

The exact cause of muscle cramp is not known, but risk factors may include:

• Tight, inflexible muscles
• Poor physical condition
• Poor muscle tone
• Inadequate diet
• Physical overexertion
• The physical exertion of cold muscles
• Muscle injury
• Muscle fatigue
• Excessive perspiration
• Dehydration – caused by, for example, about of gastroenteritis
• Reduced blood supply (ischemia)
• Wearing high-heeled shoes for lengthy periods.

Causes  of Charley Horse

The cause of muscle cramps isn’t always known. Muscle cramps may be brought on by many conditions or activities, such as:

• Exercising – injury, or overuse of muscles.
• Pregnancy – Cramps may occur because of decreased amounts of minerals, such as calcium and magnesium, especially in the later months of pregnancy.
• Exposure to cold temperatures – especially to cold water.
• Other medical conditions – such as blood flow problems (peripheral arterial disease), kidney disease, thyroid disease, and multiple sclerosis.
• Standing on a hard surface for a long time – sitting for a long time, or putting your legs in awkward positions while you sleep.
• Not having enough potassium – calcium, and other minerals in your blood.
• Being dehydrated – which means that your body has lost too much fluid.
• Taking certain medicines – such as antipsychotics, birth control pills, diuretics, statins, and steroids.
• Straining or overusing a muscle – This is the most common cause.
• Compression of your nerves – from problems such as a spinal cord injury or a pinched nerve in the neck or back
• Dehydration
• Low levels of electrolytes such as magnesium, potassium, or calcium
• Not enough blood getting to your muscles
• Pregnancy
• Certain medicines
• Getting dialysis

Possible Causes of Charley Horse

Muscle cramps can have many possible causes. They include

• Poor blood circulation in the legs
• Overexertion of the calf muscles while exercising
• Insufficient stretching before exercise
• Exercising in the heat
• Muscle fatigue
• Dehydration
• Magnesium and/or potassium deficiency
• Calcium deficiency in pregnant women
• Malfunctioning nerves, which could be caused by a problem such as a spinal cord injury or pinched nerve in the neck or back
• Calcium deficiency (in expectant mothers)
• Dehydration
• Inadequate/insufficient stretching before starting your workout
• Malfunctioning nerves as a result of such problems as pinched nerves in the back or the neck, or spinal cord injury
• Muscle fatigue

Drugs causing Charley Horse

Always exclude a medicine-related cause. Implicated drugs include

• Salbutamol and terbutaline
• Raloxifene
• Opiate withdrawal
• Diuretics cause electrolyte loss
• Nifedipine
• Phenothiazines
• Penicillamine
• Nicotinic acid
• Statin

Medications that can cause muscle cramps include

• Lasix (furosemide), Microzide (hydrochlorothiazide), and other diuretics (“water pills”) used to remove fluid from the body
• Aricept (donepezil), used to treat Alzheimer’s disease
• Prostigmine (neostigmine), used for myasthenia gravis
• Procardia (nifedipine), a treatment for angina and high blood pressure
• Evista (raloxifene), an osteoporosis treatment
• Brethine (terbutaline), Proventil and Ventolin (albuterol), asthma medications
• Tasmar (tolcapone), a medication used to treat Parkinson’s disease
• Statin medications for cholesterol such as Crestor (rosuvastatin), Lescol (fluvastatin), Lipitor (atorvastatin), Mevacor (lovastatin), Pravachol (pravastatin), or Zocor (simvastatin)

Symptoms of Charley Horse

Cramps may also occur in association with metabolic disturbance, including:

• Hyponatremia
• Hypokalemia and hyperkalemia
• Hypocalcemia
• Hypomagnesaemia
• Hypoglycemia

One or more of these may be the underlying etiology in many of the causes listed below. Blood tests measure the extracellular environment but do not reflect the intracellular fluid which is probably more important.

• Arterial insufficiency.
• Acute or chronic diarrhea.
• Excessive heat and sweating causing Na⁺ depletion.
• Hypothyroidism (associated with weakness, enlarged muscles, and painful muscle spasms).
• Hyperthyroidism (associated with myopathy).
• Lead poisoning.
• Sarcoidosis.
• Hyperparathyroidism (hypercalcemia).
• Heavy alcohol ingestion and cirrhosis.
• Hyperventilation-induced respiratory alkalosis.
• Haemodialysis.
• Parenteral nutrition.
• Lower motor neuron disorders including amyotrophic lateral sclerosis, polyneuropathies, recovered poliomyelitis, peripheral nerve injury, and nerve root compression.

Diagnosis of Charley Horse

Many patients who complain of “cramps” actually have some other related phenomenon. What characteristics, then, can be helpful in making the correct diagnosis?

• Quality – It is useful to find out about onset (abrupt or slow?), sensation (painful? stiff?), and appearance (if an abnormal posture is described, have the patient demonstrate it). With true cramps, the onset is sudden, the muscle feels taut and painful, and usually, it is visibly and palpably knotted (although this may not be readily apparent if only part of the muscle is involved).
• Location – Determine if muscles are involved singly or in groups if certain muscles are consistently involved, and if the cramps remain limited or spread. While ordinary cramps often affect the leg (especially calf) muscles, other locations may point to a specific syndrome such as carpopedal spasms in tetany or unilateral facial involvement in hemifacial spasms.
• Duration – Ordinary cramps last from seconds to several minutes if severe. Fleeting twitches or prolonged contractions suggest another type of disorder.
• Precipitating or relieving maneuvers –  Attempt to uncover any relation to exercise; specifically, find out not only if the occurrence is at rest or during or after exercise but also the duration and intensity of exercise that may initiate cramps. Moreover, clarify if the cramps appear only sporadically or can be predictably expected at a certain level of exertion. One may also want to ask about other potential triggers such as movement, sensory or emotional stimuli, hyperventilation, cold, or fasting. Assess if anything alleviates the cramps.
• The course of symptoms – A relatively recent onset suggests the possibility of acquired intercurrent illness, whereas affliction since youth may point to an inherited disorder.

Includes

• Restless legs (Ekbom’s syndrome).
• Intermittent claudication and ischaemic rest pain.
• Muscle injury or strain.
• Hypnagogic muscle jerking (when falling asleep).
• Lumbar nerve root entrapment.
• Ruptured Baker’s cyst.
• Deep vein thrombosis or thrombophlebitis.
• Peripheral neuropathy.
• Occupational cramps – eg, writer’s cramp or musician’s cramp (focal dystonias, usually affecting the upper limb).
• Causes of generalized muscle pain – eg, polymyositis, toxoplasmosis, alcohol-related myopathy, Guillain-Barré syndrome, polymyalgia rheumatic, Parkinsonism, fibromyalgia.

Potential investigations include:

• U&Es
• LFTs
• TFTs
• Serum calcium or magnesium
• Creatine kinase
• Lead levels

Treatment of Charley Horse

Limited evidence supports treating nocturnal leg cramps with exercise and stretching, or with medications such as magnesium, calcium-channel blockers, vitamin B or vitamin C. Quinine is no longer recommended to treat leg cramps.

General

• In most cases the aetiology is benign and the patient needs to be reassured of this whilst steps are taken to help alleviate the problem. Exclude known causes of muscle cramps without excessive and unnecessary investigation.
• Management depends upon the cause of the problem. Review drugs. Address any correctable problems – eg, use of diuretics and electrolyte imbalance.
• The severity of symptoms and their impact on sleep, mood and quality of life will determine whether treatment is required. Asking patients to keep a sleep and cramp diary may be helpful to assess progress.
• The evidence base for management of this common but usually benign condition is not strong.

Drug for Charley Horse

Types of prescription medications include

• Analgesics – Prescription-strength drugs that relieve pain but not inflammation.
• Anti-depressants – drugs that block pain messages from your brain and boost the effects of endorphins (your body’s natural painkillers).
• Corticosteroids – Also known as oral steroids, these medications reduce inflammation.
• Muscle Relaxants – These medications provide relief from spinal muscle spasms.
• Neuropathic Agents – Drugs that address neuropathic—or nerve-related—pain. This includes burning, numbness, and tingling.
• NSAIDs – Prescription-strength drugs that reduce both pain and inflammation.
• Opoid  – Also known as narcotics, these medications are intense pain relievers that should only be used under a doctor’s careful supervision.
• Topical Medications – These prescription-strength creams, gels, ointments, patches, and sprays help relieve pain and inflammation through the skin.

Non-drug

There is only limited evidence for the use of non-drug therapies for the treatment of lower-limb muscle cramps.

• Passive stretching and massage of the affected muscle. This will help ease the pain of an acute attack – eg, for calf cramping, straighten the leg with dorsiflexion of the ankle or heel walk until the acute pain resolves.
• Regular stretching of the calf muscles throughout the day. This may help to prevent acute attacks. Some people recommend stretching three times daily whilst others advocate stretching before going to bed.
• Using a pillow to raise the feet through the night or raising the foot of the bed. This may help to prevent attacks in some people.
• Note that whilst stretching exercises are unlikely to do harm, evidence for their efficacy is contradictory. In sport, stretching is widely advocated as likely to reduce injury and cramp but the quality of evidence tends to be poor, with failure to distinguish benefit from that due to improvement in physical fitness from training.
• Avoiding over-training and risky conditions (eg, hot and humid environmental conditions) can be useful in preventing cramps

Quinine –

• some preliminary studies have found that a number of people benefit from taking quinine. There is no information yet about quinine’s safety and long-term effectiveness. Some doctors may recommend quinine if the stretching has not helped, attacks are frequent, and/or the patient’s quality of life is being undermined by the leg cramps. A course of treatment usually lasts from four to six weeks – the patient takes the medication just before going to bed.
• Pregnant women should not take quinine. Individuals who had a previous reaction to quinine, those with previous hemolytic anemia, optic neuritis, and/or glucose 6-phosphate dehydrogenase deficiency should not take quinine.
• As the quinine dosage is very low, side effects are rare. In rare cases the patient may develop a blood disorder. Some patients may develop cinchonism after long-term quinine therapy, which may cause vomiting, nausea, vision and/or hearing problems and dizziness.

How do I Avoid Muscle Cramp

In looking at the above risk factors, you can reduce your risk of cramping by trying the following tips:

• Maintain your fitness.
• Stretch regularly. 5 minutes of gentle stretching on the floor during a TV ad break each evening can be sufficient to drastically improve flexibility. Hold each stretch so that you are straining but not feeling pain, and release after 30 seconds.
• Ensure you are getting the right minerals to maintain proper muscle function. Eating a varied diet is the best way to get a range of minerals. Cacao is a rich natural source of magnesium.
• Try a supplement. Getting your RDI of some minerals is tough to do from food alone (adult women, for example, need 1300mg of calcium each day. That’s more than 4 glasses of milk). If you think you are struggling to get enough nutrients into your diet to stop cramping, you may benefit from taking a multivitamin that contains magnesium and nutrients to aid muscle relaxation or:
•  Incorporate a Magnesium powder sourced from wholefoods (more readily absorbed by the body than tablets) OR Cacao Powder (cacao is rich in magnesium and potassium). It is possible to have too much magnesium, yet the side effects at the upper limit of recommended daily magneisum intake have not been shown to produce toxic effects when ingested as naturally occurring magnesium in food (according to nrv.gov.au) as contrasted against magnesium tablets.
• Try a Calcium Supplement or Chia Seeds (chia seeds are incredibly rich in calcium, critical for muscles).
• Ensure you are drinking enough fluids throughout the day, especially before, during and after periods of physical exertion. Drink a glass of water first thing when you wake up in the morning to top up any fluids lost during sleep.
• Know your exercise boundaries. In hot/humid conditions, take it easy to avoid excessive perspiration.
• If muscle cramps persist despite trying the above, see your doctor. Genetic factors, diseases such as atherosclerosis or sciatica or some prescription medications may be contributing.

Natural remedies for muscle cramps

• Mix 1 part oil of wintergreen – (available from pharmacies or essential oils suppliers) with 4 parts vegetable oil and massage it into the cramp. Wintergreen contains methyl salicylate (related to aspirin), which relieves pain and stimulates blood flow. You can use this mixture several times a day, but not with a heating pad–it could burn your skin. (Caution: Note that wintergreen is highly toxic when swallowed.)
• Cramp bark has long been used as a muscle relaxant – A medical herbalist can makeup both a tonic to be taken internally and a rubbing lotion from this herb.
• Take a long, warm shower or soak in the bath – For added relief, pour in half a cup of Epsom salts. The magnesium in Epsom salts promotes muscle relaxation.
• Place an electric heating pad or a hot face washer – on the troublesome muscle to relax the cramp and increase blood flow to the affected tissue. Set the pad on low, apply for 20 minutes, then remove it for at least 20 minutes before reapplying.
• Find the central point of the cramp – Press this spot with your thumb, the heel of your hand or a loosely clenched fist. Hold the pressure for 10 seconds, ease off for 10 seconds, then press again. You should feel some discomfort but not excruciating pain. After repeating this action several times, the pain should start to diminish.
• Muscle cramps from dehydration – Cramps are often caused by dehydration, so if you get cramps frequently, drink more water.

If you tend to get cramps during exercise, drink at least 2 cups of water 2 hours before each work-out. Then stop and drink 100–250ml every 10 to 20 minutes during your exercise sessions. If you sweat a lot, consider a sports drink, such as Lucozade Sport, that replaces lost sodium and other electrolytes.

Minerals that prevent muscle cramps

• Low levels of minerals known as electrolytes – which include potassium, sodium, calcium and magnesium, can contribute to cramps. You probably don’t need more sodium (salt) in your diet, but you may need other minerals. Good food sources of magnesium are wholegrain breads and cereals, nuts and beans. Potassium is in most fruits and vegetables, especially bananas, oranges and apricot. And dairy foods supply calcium. If you change your diet and you still get cramps, take 500mg of calcium and 500mg of magnesium twice a day, adding up to 1000mg of each supplement, or as professionally prescribed. Some people who get leg cramps due to a magnesium deficiency obtain rapid relief from supplements. Don’t take magnesium without calcium; the 2 minerals work as a pair.
• If you take diuretics for high blood pressure – your increased need to urinate may be robbing you of potassium. The result is a condition called hypokalemia, which can cause fatigue, muscle weakness and muscle cramps. Ask your doctor if you can switch to a blood-pressure medication that isn’t a diuretic.

Muscle cramps at night

• Drink a glass of tonic water – which contains quinine, before bedtime. Research supports the use of quinine for nocturnal leg cramps, but don’t take it as tablets; they can have serious side effects, such as ringing in the ears and disturbed vision.
• To prevent night-time calf cramps – try not to sleep with your toes pointed. And don’t tuck in your sheets too tightly as this tends to bend your toes downwards, causing cramp.
• Take 250mg of vitamin E a day –  to improve arterial blood flow, thus potentially preventing night-time leg cramps. Muscle cramps are usually temporary and don’t cause permanent damage, but contact your doctor if the cramp or spasm lasts for more than a day, or if it continues to bother you despite trying these home remedies. And call immediately if the spasm occurs in the lower back or neck, accompanied by pain that radiates down your leg or into your arm. Finally, if abdominal cramps occur in the lower right-hand part of your belly, it could signal appendicitis.

References

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Retinal detachment (RD), defined as the separation of the neurosensory retina from the underlying retinal pigment epithelium (RPE), can cause devastating visual loss. With advances in surgical techniques, the anatomical reattachment rate has greatly increased, especially after repeated surgery [rx, rx]. However, the final visual outcome remains, in many cases, disappointing once the retinal detachment involving the macula. Even with total retinal reattachment, long-term post-operative VA may lie anywhere in the range of 0.2 to 0.4 [rx]. Photoreceptor apoptosis has been postulated to be the main reason for such visual loss [rx–rx], alongside other structural changes in the retina such as glial scarring [rx]. Neuroprotection has thus become a focus of research to achieve a better visual outcome by preventing or reducing photoreceptor cell death.

Retinal detachment is a disorder of the eye in which the retina separates from the layer underneath.^[rx] Symptoms include an increase in the number of floaters, flashes of light, and worsening of the outer part of the visual field.^[rx][rx] This may be described as a curtain over part of the field of vision.^[rx] In about 7% of cases, both eyes are affected.^[rx] Without treatment, permanent loss of vision may occur.^[rx]

Types of Retinal Detachment

Retinal detachment (RD) is broadly classified into three types based on clinical appearance and underlying etiology.

• Rhegmatogenous retinal detachment (RRD) – where the RD develops due to a retinal break (‘rhegma’, meaning rent or a fissure) [rx]. Fluid, from the vitreous cavity, passes through the retinal break into the potential space under the retina, leading to separation of the retina from the underlying choroid. This requires surgical treatment.
• Tractional retinal detachment (TRD) – which occurs due to pre-retinal membrane formation and scarring that pulls the retina from its attachment. This may require surgery depending on the extent of the RD. The commonest causes of TRD are diabetes, Eales’s disease, sickle cell retinopathy, and trauma.
• Exudative and serous retinal detachments – occur due to abnormalities in water transport across the bed of the retina (retinal pigment epithelium) or in its blood supply.

Tractional and exudative/serous retinal detachments are less common and will not be discussed in this paper.

Causes of Retinal Detachment

Rhegmatogenous

Symptoms of Retinal Detachment

A rhegmatogenous retinal detachment is commonly preceded by a posterior vitreous detachment which gives rise to these symptoms

• The detachment is visible as a grey, mobile membrane inside the eye.
• Intraocular pressure may be reduced
• The red reflex is usually pale, or grey, rather than the normal orange
• When examining the eye using a slit lamp, you may see pigment cells in the vitreous.
• Very brief flashes of light (photopsia) in the extreme peripheral (outside of center) part of a vision
• A sudden dramatic increase in the number of floaters
• A ring of floaters or hairs just to the temporal (skull) side of the central vision

Although most posterior vitreous detachments do not progress to retinal detachments, those that do produce the following symptoms

• The sudden appearance of many floaters — tiny specks that seem to drift through your field of vision
• Flashes of light in one or both eyes (photopsia)
• Blurred vision
• Gradually reduced side (peripheral) vision
• A curtain-like shadow over your visual field
• The dense shadow that starts in the peripheral vision and slowly progresses towards the central vision
• The impression that a veil or curtain was drawn over the field of vision
• Straight lines (scale, the edge of the wall, road, etc.) that suddenly appear curved (positive Amsler grid test)
• Central visual loss.

In the event of an appearance of sudden flashes of light or floaters, an eye doctor needs to be consulted immediately.^[rx] Any loss of vision is also a medical emergency.

Diagnosis of Retinal Detachment

• A retinal examination – The doctor may use an instrument with a bright light and special lenses to examine the back of your eye, including the retina. This type of device provides a highly detailed view of your whole eye, allowing the doctor to see any retinal holes, tears or detachments.
• Retinal detachment can be examined – by fundus photography or ophthalmoscopy. Fundus photography generally needs a considerably larger instrument than the ophthalmoscopy but has the advantage of availing the image to be examined by a specialist at another location and/or time, as well as providing photo documentation for future reference.
• Modern fundus photographs – generally recreate considerably larger areas of the fundus than what can be seen at any one time with handheld ophthalmoscopes.
• Ultrasound – has diagnostic accuracy similar to that of examination by an ophthalmologist.^[rx] The recent meta-analysis shows the diagnostic accuracy of emergency department (ED) ocular ultrasonography is high. The sensitivity and specificity ranged from 97% to 100% and 83% to 100%.^[rx]
• The typical feature of retinal detachment – when viewed on ultrasound, is “flying angel sign”. It shows the detached retina moving with a fixed point under the B mode, linear probe 10 MHz.^[rx]

Treatment of Retinal Detachment

There are several methods of treating a detached retina, each of which depends on finding and closing the breaks that have formed in the retina. All three of the procedures follow the same three general principles:

• Find all retinal breaks
• Seal all retinal breaks
• Relieve present (and future) vitreoretinal traction
• Laser coagulation – the laser light enters the eye via the pupil. The laser energy is absorbed in the retinal pigment epithelium, leading to heat (ca. 60 °C) and coagulation necrosis [rx, rx]. Cryocoagulation involves freezing of the eyeball all the way from the outside to the retina by application of a cryoprobe (ca. –80 °C). Both procedures are followed after a few days by the formation of a scar, but only if the retina is in contact with the underlying retinal pigment epithelium. Therefore, scar induction by either laser coagulation or cryocoagulation is effective only for prevention of detachment in a still-attached retina; both forms of coagulation are pointless if detachment has already occurred.
• Funduscopy – A detachment is recognized by the dune-like appearance and mobility of the retina, and the hole responsible for the detachment can often be discerned. The procedures employed for surgical management of retinal detachment are scleral buckling and vitrectomy. Here too laser coagulation or cryocoagulation is used for hole closure, but only after surgery to repair the detachment. Data for both of these surgical options are available from recent prospective randomized clinical trials.
• Scleral buckling – After precise localization of all retinal breaks and marking of the sclera, the holes are treated with cryopexy for scar induction. The traction exerted on the holes by the vitreous body is then reduced by a foam sponge sutured to the sclera [rx]
• Scleral buckle surgery – is an established treatment in which the eye surgeon sews one or more silicone bands (or tires) to the sclera (the white outer coat of the eyeball). The bands push the wall of the eye inward against the retinal hole, closing the break or reducing fluid flow through it and reducing the effect of vitreous traction thereby allowing the retina to re-attach. Cryotherapy (freezing) is applied around retinal breaks prior to placing the buckle. Often subretinal fluid is drained as part of the buckling procedure
• Pneumatic retinopexy – This operation is generally performed in the doctor’s office under local anesthesia. It is another method of repairing a retinal detachment in which a gas bubble (SF_6[rx] or C₃F_8[rx] gas) is injected into the eye after which laser or freezing treatment is applied to the retinal hole. The patient’s head is then positioned so that the bubble rests against the retinal hole. Patients may have to keep their heads tilted for several days to keep the gas bubble in contact with the retinal hole. The surface tension of the gas/water interface seals the hole in the retina, and allows the retinal pigment epithelium to pump the subretinal space dry and “suck the retina back into place”.
• Vitrectomy – Vitrectomy begins with the removal of the vitreous humor causing the retinal detachment, followed by displacement of the subretinal fluid by means of a heavy tamponade (perfluorodecalin or perfluorocarbon) and scarring of the retina by laser coagulation or cryocoagulation. The vitreous is then replaced by a tamponade[rx], which holds the retina against the underlying retinal pigment epithelium until a firm scar has formed around the retinal hole. A mixture of air and gas or a silicone oil tamponade can be chosen for this purpose. The air/gas mixture is usually chosen in simpler situations (e.g., when the hole is at the top of the eyeball). The advantage of the air/gas tamponade is that it is absorbed and thus does not require removal.
• Injecting air or gas into your eye – In this procedure, called pneumatic retinopexy, the surgeon injects a bubble of air or gas into the center part of the eye (the vitreous cavity). If positioned properly, the bubble pushes the area of the retina containing the hole or holes against the wall of the eye, stopping the flow of fluid into space behind the retina. Your doctor also uses cryopexy during the procedure to repair the retinal break.
• Indenting the surface of your eye – This procedure, called scleral (SKLAIR-ul) buckling, involves the surgeon sewing (suturing) a piece of silicone material to the white of your eye (sclera) over the affected area. This procedure indents the wall of the eye and relieves some of the force caused by the vitreous tugging on the retina. If you have several tears or holes or an extensive detachment, your surgeon may create a scleral buckle that encircles your entire eye like a belt. The buckle is placed in a way that doesn’t block your vision, and it usually remains in place permanently.
• Draining and replacing the fluid in the eye – In this procedure, called vitrectomy, the surgeon removes the vitreous along with any tissue that is tugging on the retina. Air, gas or silicone oil is then injected into the vitreous space to help flatten the retina.

Health Tips  for Home Treatment

Retinal detachment may cause you to lose vision. Depending on your degree of vision loss, your lifestyle might change significantly.

You may find the following ideas useful as you learn to live with impaired vision:

• Get glasses – Optimize the vision you have with glasses that are specifically tailored for your eyes. Request safety lenses to protect your better-seeing eye.
• Brighten your home – Have proper light in your home for reading and other activities.
• Make your home safer – Eliminate throw rugs and place colored tape on the edges of steps. Consider installing motion-activated lights.
• Enlist the help of others – Tell friends and family members about your vision problems so they can help you.
• Get help from technology – Digital talking books and computer screen readers can help with reading, and another new technology continues to advance.
• Check into transportation – Investigate vans and shuttles, volunteer driving networks, or ride shares available in your area for people with impaired vision.
• Talk to others with impaired vision – Take advantage of online networks, support groups, and resources for people with impaired vision.

References

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Parasitic 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”]

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Fungal 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”]

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

Viral Meningitis, Causes, Symptoms, 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”][wpedon id=”117664″ align=”center”]

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