Evaluation of cerebrospinal fluid (CSF) C-reactive protein in the diagnosis of suspected meningitis.

Cerebrospinal fluid C-reactive protein (CSF-CRP) was studied in 183 consecutive infants and children with suspected meningitis, using a nephelometric technique. Cerebrospinal fluid C-reactive protein was above an empirically chosen level of 1 mg/1 in seven of 19 children with culture-proven bacterial meningitis, in only one of 15 children with viral meningitis, and three of 139 children with no meningitis. All 10 children with partially treated meningitis had CSF-CRP levels below 1 mg/1. There was good correlation between CSF-CRP and total protein levels in children with bacterial meningitis (R value 0.4999 P less than 0.05). The test was not sensitive enough for early differentiation between bacterial and viral meningitis. The test also did not add extra information regarding aetiology in partially treated meningitis.