White blood cell count, erythrocyte sedimentation rate and serum C-reactive protein in meningitis: magnitude of the response related to bacterial species.

White blood cell count (WBC), erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP) were determined upon diagnosis of 61 children with bacterial meningitis in order to compare the responses evoked by different bacteria. The age of the patients and the duration of their symptoms were similar in all groups. WBC and ESR corresponded significantly with the bacterial species. The mean WBC in Haemophilus influenzae (n = 44), meningococcal (n = 11) and pneumococcal (n = 6) infection were 14,605/microliters 19,391/microliters and 23,833/microliters, respectively (for H. influenzae and pneumococci p less than 0.001). The mean ESR varied from 58 mm/h (meningococci) to 100 mm/h (pneumococci) (p less than 0.025). CRP was the test least influenced by the nature of the bacteria. The characteristics of CRP suggest its superiority over WBC and ESR as a detector of bacteremic infections. WBC is unsuitable for screening of systemic H. influenzae disease.