What is Meningitis?
Meningitis is an infection of the covering of the brain. It is most commonly caused by a germ called the meningococcus. This is frequently present in the throat of many adults, even though it may never cause symptoms. However, if the patient suffers from an upper respiratory tract infection (such as a common cold or bout of the flu), symptoms may set in rapidly. It may also complicate any sort of infection in this general area.
Infected middle ears may be a relatively common cause. Infected sinuses, infections of the face, scalp, eye, or penetrating injuries and wounds are all known causes. Also, in more serious conditions, it may spread to the brain via the bloodstream, and it may complicate more serious diseases such as carcinoma (cancer) and leukemia. Fortunately these are relatively rare. Whatever the basic cause or the causative germ, the symptoms are usually much the same.
Frequently the onset is abrupt, with a high temperature, headache, nausea and vomiting. It may have been preceded by general symptoms for about 48 hours of the causative illness, such as a respiratory or ear infection. The temperature may rise to 102° to 103°F (38.9° – 39.5°C). The headache may become extreme, and neck stiffness is usually characteristic. This is caused by meningeal irritation (the germs produce irritation of the brain coverings, the meninges), and in turn this causes spasm of the muscles of the neck. There may be pains in the neck, abdomen and extremities.
Delirium, stupor and coma appear in severe cases. The headache is commonly worse toward the back. Photophobia, an intense dislike for light, takes place. Typically the patient lies on the side, facing away from the light, resenting any interference, and remaining fairly quiet while left undisturbed. Sometimes there is head retraction, due to the spasm of the neck muscles. In about 40 per cent of cases there is a rash, which is often most prominent on the limbs.
In infants the symptoms are less obvious. Often the attack may commence with a convulsion. Between fits the infant may be irritable and unwilling to take feeds, dislike being disturbed and cry often if picked up. Vomiting may take place, and this may be “projectile,” spurting out in a forceful manner. Dehydration may be a problem, due to the vomiting.
Meningitis is an acute disease that must be treated promptly by the doctor, often in hospital. Symptoms are usually such that a person will call for medical attention, and the symptoms described certainly mean that immediate expert treatment is essential. In epidemics the overall mortality rate is still about 10 percent, but the sooner a diagnosis can be made and the correct therapy instituted, the greater are the chances of a rapid cure.
Special investigation rapidly indicates the most desirable treatment, and the antibiotic of first choice. This is often one of the penicillins, and sulks are used. Isolation is still advocated in some centers to prevent the spread, particularly if epidemics are about.
In recent times vaccines aimed at preventing meningitis have been developed, and these are being used in certain situations where large numbers may he at special risk.
There has been some concern recently because variations of the germ are emerging that appear to be insensitive to the penicillins, the basis of treatment. The full significance of this has not yet become obvious, and so far it seems to be confined to certain areas.
In the overall picture, therapy is good. As one medical authority recently stated: Theoretically no patient should die from meningococcal meningitis, as the organism is always sensitive to sulfonamides or penicillin or related products. Many series have produced mortalities of less than 1 percent. Delay in onset of treatment due to diagnostic errors is the most important factor responsible for the present mortality. A vaccine to protect against meningitis has been produced, but not widely used.
Many variations from the acute and serious form of meningitis occur, a fairly common one being viral meningitis. This may complicate other viral infections, such as mumps, glandular fever or simple respiratory infections, or it may occur on its own. The patient is rarely as sick as with meningococcal meningitis, and the symptoms are much less severe. Often a headache and mild fever may be the only symptoms. It may be preceded by an upper respiratory infection, caused by viral invasion. The outlook is invariably good, and it seldom carries the same risks and prognostic fears of the bacterial forms. On rare occasions convulsions occur and there may be residual mental deterioration, but this is not typical.
Treatment is usually along routine symptomatic lines, for there is no antibiotic that will kill viruses at present. Medical supervision by the doctor is advisable, for sometimes there may be diagnostic difficulties and the symptoms may indicate other serious disorders. But the doctor will most likely order treatment similar to that prescribed for the common cold and general respiratory tract infections. (Refer to that section.)
Other Forms of Meningitis
Various other forms of meningitis may occur, and these are usually caused by bacterial invasion of the brain coverings from a similar form of infection in some other part of the body. So there may be infections due to the pneumococcus, the streptococcus or the tubercle bacillus (the latter now being rare following a general decline of tuberculosis in the community).
The general symptoms are similar to those of meningitis produced by the meningococcus. There may be obvious infections in other places such as in the lungs, the middle ear, sinuses or elsewhere. To determine the cause, cerebrospinal fluid must be examined. This is the fluid that constantly bathes the brain and spinal cord.
This means that a procedure called a lumbar puncture is carried out by the doctor. Fluid is withdrawn from the spinal canal, and germs present in this are “cultured.” This is a process allowing them to grow artificially. They arc then tested with various antibiotics. This first identifies the organism, and second indicates which antibiotic is the most likely one to prove suitable in treating the patient. Diagnosis and treatment of these cases must take place in a hospital fully equipped to handle the necessary procedures.