MENINGITIS, a term in medicine applied to inflammation affecting the membranes of the brain (cerebral meningitis) or spinal cord (spinal meningitis) or both.
Tuberculous meningitis (or Acute Hydrocephalus) is a disease due to inflammation of the meninges of the brain produced by B. tuberculosis. It is most common in children under ten years of age, but may affect adults and is a local manifestation, de pendent upon local conditions of a generalized miliary tuberculosis the origin of which is often situated in the bronchial or mesenteric glands.
Certain features characterize the disease in each of its three stages. The premonitory symptoms are mostly nutritive. Wasting and loss of strength often precede the characteristic phenomena of the disease. The patient, if a child, becomes listless, easily fatigued, loses appetite, and is restless at night. There is headache and unusual irritability. These symptoms may persist during many weeks or the disease may come on suddenly. Onset generally begins with vomiting, convulsions or wryneck and with obstinate constipation. Headache is constant, intense and accompanied by a peculiar and characteristic cry especially at night. There is intolerance of light and sound, temperature is yet the pulse is rather slow and irregular ; breathing is irregular. Such symptoms, after one to two weeks, are followed by the stage of depression in which the patient becomes quieter from the existence of partial stupor. Vomiting ceases, there is less fever, pulse and breathing are slower and shallower and there is little suffering. The pupils are often dilated or unequal and scarcely respond to light; there may be squint or drooping of an eyelid. The patient can be roused, but is irritable and otherwise lies in apathy. In the final stage there is generally return of fever, con vulsions, perhaps paralysis of limbs, and coma is profound though swallowing remains. Death is sudden in a fit, or gradual from exhaustion and takes place within three weeks from the onset of symptoms. Though much can be done to avert the onset of the original tuberculous infection (see TUBERCULOSIS) no measure is known whereby tuberculous meningitis, once it has started, can be cured or a fatal event averted.
Pathologically the brain shows a yellow fibrinous inflammatory exudation beneath the pia mater and particularly in the lozenge shaped space at the base and in the Sylvian fissure. On floating some of the membrane in water minute tubercles may of ten be seen along the course of the Sylvian vessels.
In what is known as suppurative, or simple acute meningitis (non-tuberculous), the disease arises from various causes, e.g., middle ear disease, cerebral abscess, and the symptoms are similar to those described above.
In posterior-basic meningitis, inflammation of the membranes investing the posterior basis of the brain and the spinal cord, the chief symptoms are fever, with severe pain in the back or loins shooting downwards into the limbs (which are the seat of frequent painful involuntary startings), accompanied with a feeling of tightness round the body.
The local symptoms bear reference to the portion of the cord the membranes of which are involved. Thus when the inflamma tion is located in the cervical portion the muscles of the arms and chest are spasmodically contracted, and there may be difficulty in swallowing or breathing, or embarrassed heart action, while when the disease is seated in the lower portion, the lower limbs and the bladder and rectum are the parts affected in this way. At first there is excited sensibility (hyperaesthesia) in the parts of the surface of the body in relation with the portion of cord affected. As the disease advances these symptoms give place to those of partial loss of power in the affected muscles, and also partial anaesthesia. These various phenomena may entirely pass away, and the patient after some weeks or months recover; or, on the other hand, they may increase, and end in permanent paralysis.
Cases of posterior basic meningitis are now regarded as sporadic and somewhat peculiar examples of spinal meningitis (q.v.) or cerebrospinal meningitis. Still, William Hunter and George Nuttall isolated an organism similar to the diplococcus intra cellularis (or meningococcus), while Henry Koplik in New York found cases of typical posterior basic meningitis due to the diplococcus intracellularis. The treatment is that for spinal meningitis.