Meningitis (NHS Article)

Introduction

The meninges are the membranes that line the brain and spinal cord (central nervous system). They act as a barrier between the central nervous system and the rest of the body, acting as an extra barrier to infection. Meningitis is infection of the meninges. It can be caused by bacteria or viruses. There are approximately 3500-4000 reported cases per year in the UK.

• Bacterial meningitis is less common but always a serious and severe illness.
• Viral meningitis is more common and normally less serious.

Bacterial meningitis is caused by several different types of germs which live naturally at the back of the nose and throat in one in ten people and can be spread by close prolonged contact, coughing, sneezing and kissing. Only in some do the germs overwhelm the bodies defences and cause meningitis. The bacteria cannot live long outside the body so cannot be picked up from water supplies, swimming pools, buildings or factories and only certain types of bacteria (meningococcal C) spread more rapidly rapidly in crowded areas. Incubation for bacterial meningitis is between 2 and 10 days.

Viral meningitis is a less severe illness but can still be very debilitating, and very rarely, can progress through headache, fever and drowsiness to deep coma. The incubation period for viral meningitis can be up to 3 weeks.

Symptoms

Symptoms may not be easy to identify as meningitis because initially, they can be similar to those of flu. The symptoms below may appear in any order over 1-2 days or in a matter for hours and some of them may not appear at all. It is also possible that there may be additional symptoms.

In adults and older children;

• high temperature, vomiting, sometimes diarrhoea, severe headache, neck stiffness (unable to touch chin to chest), aversion to bright light, sore throat, drowsiness, joint or muscle pains, stomach cramps, fits, confusion, disorientation

In babies and infants;

• high temperature, fever (possibly with cold hands and feet), vomiting and refusing feeds, high pitched moaning, whimpering cry, blank staring expression, pale blotchy complexion, floppiness, dislike of being handled, fretful, neck retraction with arching of back, convulsions, difficult to wake, lethargic, tense or bulging fontanelle (soft spot on head)

Meningitis is very serious, in babies and young children death can occur in a matter of hours if left untreated. In some cases, the acute illness subsides into a persistent (chronic) state, which may lead to serious brain damage. If you suspect meningitis you must seek urgent medical assistance.

Sometimes, but not always, the bacteria which cause meningitis can cause septicaemia (blood poisoning) which is a medical emergency needing urgent treatment with antibiotics. A rash of purple-red spots can appear starting anywhere as a cluster of tiny blood spots which join to give the appearance of fresh bruises. If you suspect meningitis you should not wait for the rash to appear.

The glass (tumbler) test can be used to determine if a rash might be septicaemia by pressing the side of a clear drinking glass onto the rash or bruises and checking that they fade. If they don't fade suspect septicaemia. In a small number of cases the rash may fade at first but may later change into one that doesn't fade.

Viral meningitis is a less severe illness but, very rarely, can progress through headache, fever and drowsiness to deep coma. In severe cases there may be weakness of the muscles, paralysis, speech disturbances, double vision or partial loss of the field of vision, and epileptic fits. Most people make a full recovery within one to two weeks, occasionally there maybe long term problems such as hearing or memory impairment.

Causes

Any bacteria or virus has the potential to cause meningitis.

Bacterial meningitis is caused by several different types of germs which live naturally at the back of the nose and throat and can be spread by close prolonged contact, coughing, sneezing and kissing.

In the UK the most common cause of bacterial meningitis is infection with the meningococcal or pneumococcal bacteria, but Hib, TB, E.Coli, and Group B streptococcal bacteria can also cause meningitis.

Viral meningitis may be caused by viruses such as coxsackie, herpes simplex, mumps, the varicella zoster virus of chickenpox and shingles, poliovirus, echoviruses (including enterovisuses). Germs can be spread through coughing, sneezing, poor hygiene or sewage polluted water.

Meningitis can also be a feature of other diseases, including Lyme disease, Leptospirosis, Typhus, Tuberculosis and other infections.

Diagnosis

This is made on the basis of the symptoms and clinical signs, the culture of the germs from the blood, and analysis of cerebrospinal fluid through lumbar puncture (see article on Lumbar puncture). Stiff neck is an important sign. If meningitis is suspected, antibiotics must be given immediately without waiting for confirmation from germ culture.

Prevention

There is no known way to prevent meningitis, it is therefore important to be aware of the danger signs. If someone becomes unwell they may deteriorate quickly so medical advice must be sought if you suspect meningitis or septicaemia.

Vaccines are available against meningococci groups A and C and against Haemophilus influenzae (HiB), which can also cause meningitis. Meningococcal C and HiB now form part of the routine national immunisation schedule for child health.

Treatment

Urgent treatment with antibiotics and appropriate hospital management is essential for someone with bacterial meningitis. The sooner they are diagnosed and treated, the greater chance there is they will make a full recovery. Anyone who has been in direct, close, prolonged contact with the infected person (normally family members and those deemed to be at an increased risk) should be given appropriate protective antibiotics if necessary.

Viral meningitis cannot be helped by antibiotics and treatment is based on good nursing care. Recovery is normally complete, but headaches, tiredness and depression may persist for weeks or even months.