MENINGITIS - Full extract 

Meningitis means an infection of the meninges, the tissues that cover the brain and the spinal cord. 
Viral meningitis is the most common type and may occur by itself or as a complication of some other viral infection like mumps. Usually no specific treatment is required. 
Bacterial meningitis is a much more serious illness and can be life-threatening. In pre-antibiotic days it had a greater than 90% mortality rate, and those that did recover nearly always had permanent disabilities like deafness and blindness. Undiagnosed or untreated it has a similar mortality rate today; hence the vital importance of early diagnosis and treatment.
Other uncommon forms of meningitis can occur, for instance those caused by TB, syphilis, and certain yeasts and fungal infections. Some of these infections are more likely in people whose immune systems are not working properly. Bacterial meningitis can be caused by a variety of bacteria, depending largely on the age of the patient.

Pneumococcal meningitis is the most common form of bacterial meningitis in infants and the elderly. It is also the most severe. Even with modern treatment it has a 10% mortality rate and about 40% incidence of complications such as deafness, blindness, spasticity and learning difficulties. A major concern is the increasing occurrence of penicillin-resistant strains of pneumococcus. This could be as high as 40% in the next few years. A vaccine is currently available for those at risk of pneumococcal infection.

Hamophilus influenza Type b (Hib). Until recently Hib was the major cause of bacterial meningitis in infants up to the age of five. It also causes another very severe condition called epiglottitis where the breathing-passage in the throat can become completely blocked. In the last five years immunization against Hib disease has been added to routine infant immunizations. The rates of Hib infection have fallen dramatically and it is likely that Hib disease will soon be fully eradicated. 

Meningococcal infection causes regular outbreaks of bacterial meningitis in Australia. It is very contagious and usually occurs in children and young adults. Sometimes a fine purply rash is present. If someone develops this infection, close contacts are usually traced and given preventive antibiotics. If a major outbreak occurs, a meningococcal vaccine may also be advised. It is quite common in parts of the world like India, Africa and parts of Asia, and immunization is recommended for people travelling to those areas. 

Several other types of bacterial meningitis can occur. In newborn babies it can be caused by bacteria called E.Coli. 

The main symptoms of meningitis are headache, fever, nausea and vomiting. Light is often very irritating to the eyes, and there may be a degree of neck stiffness. With young children the diagnosis may not be obvious; the signs may be as vague as poor feeding, fever, increasing drowsiness or just looking sick. With meningococcal infection a rash may be evident. In severe cases, convulsions and coma may occur. 

The main diagnostic test for meningitis is a lumbar puncture; a few drops of spinal fluid are collected by inserting a fine needle into the space around the low part of the spine. It is a relatively simple procedure done under local anaesthetic. The fluid is examined under the microscope to see if meningitis is present and whether the infection is bacterial or viral. It is then put on culture media to see if any bacteria will grow for identification. 

As well as the lumbar puncture, blood tests are also arranged. In some cases, a special X-ray of the brain called a CT scan may also be performed. 

Viral meningitis usually resolves completely without specific treatment. In contrast, bacterial meningitis is a medical emergency; high dose intravenous antibiotics are essential, sometimes in an intensive care unit. 

Health Tips:
* Hib meningitis is a disease that is totally preventable with routine childhood immunization. 

* A child who is thought to have a simple infection and then deteriorates should be urgently reviewed by your doctor. Bacterial meningitis may not be obvious initially.

Dr. Andrew Pattison: Common Consultations
North East Valley Division General Practice, Melbourne, Australia.   Disclaimer
  - Last modified: August 18, 2001