Retrospective review of clinical and neuroimaging observations in pyomeningitis.

The present study is a review of patients with pyogenic meningitis diagnosed by clinical and laboratory criteria in which CT scan was done to detect acute phase CT abnormalities with respect to post inflammatory hydrocephalus and ventriculomegaly. Fifty-six patients were identified between 1993 and 1996 in the Department of Pediatrics at the All India Institute of Medical Sciences, New Delhi. A CT scan was available in 30. The diagnosis was compatible with a definitive pyogenic meningitis in 17 and probable pyogenic meningitis in 13. The acute stage CT scans performed within the first four weeks of illness revealed ventriculomegaly in 10 out of 30 bacterial meningitis (33%), (41.1% of definitive meningitis compared to only 23% of the probable meningitis group). Follow-up CT scans revealed persistent ventriculomegaly in 2. Both patients with persistent ventriculomegaly had frontal atrophy. None of the patients merited a shunt or any medical measures. Cortical atrophy as an aftermath of acute bacterial meningitis may cause persistent ventriculomegaly. The frontal cortex localization may explain the frequency of seizures and other sequelae observed in pyogenic meningitis. An early recognition may help to prognosticate patient outcome.