Bacterial infections of the leptomeninges and subarachnoid space, frequently involving the cerebral cortex, cranial nerves, cerebral blood vessels, spinal cord and nerve roots; causative organism varies with age and clinical status (eg, postoperative, immunodeficient, posttraumatic states); clinical manifestations include the acute onset of fever, stiff neck, altered mentation, seizures, and focal neurologic deficits; death may occur within 24 hours of disease onset; pathologic features include a purulent exudate in the subarachnoid space, and diffuse inflammation of neural and vascular structures.
Bacterial infections of the leptomeninges and subarachnoid space, frequently involving the cerebral cortex, cranial nerves, cerebral blood vessels, spinal cord, and nerve roots.
Bacterial infections of the nervous system caused by haemophilus organisms, and marked by prominent inflammation of the meninges. Haemophilus influenzae type b is the most common causative organism. The condition primarily affects children under 6 years of age but may occur in adults. Clinical manifestations include fever; nuchal rigidity; photophobia; seizures; hearing loss, sensorineural; coma; and cerebrovascular thrombosis. The organism tends to enter the central nervous system following infections of adjacent structures, including the middle ear (see also otitis media), sinuses, and pharynx. (from menkes, textbook of child neurology, 5th ed, pp396-7)