Aseptic meningitis after neurosurgery: a demonstration of bacterial involvement.

OBJECTIVE: To evaluate the presence of bacteria in samples from patients suffering from 'aseptic' meningitis following craniotomy. METHODS: Prospective study in which cerebrospinal fluid (CSF) from patients suffering from post-craniotomy meningitis and negative control patients were submitted to conventional culture and to polymerase chain reaction (PCR) using bacterial 16S rRNA universal primers, followed in some cases by DNA sequencing of the PCR product and phylogenetic analysis. RESULTS: CSF from patients with either culture-positive or culture-negative meningitis yielded positive amplifications, whereas no amplification was obtained with CSF from control patients.