Effectiveness of cefotaxime in gram-negative meningitis.

We treated 12 adult patients who had gram-negative bacillary meningitis with cefotaxime administered intravenously at a dose of 2 g every 4 hours. The etiological organisms included Haemophilus influenzae (3 cases), Serratia marcescens (3 cases), Klebsiella pneumoniae (3 cases), Escherichia coli (2 cases), and Enterobacter (1 case). The infection followed a neurosurgical procedure in 6 cases. The mean inhibitory and bactericidal concentrations of cefotaxime for the isolates ranged from 0.125 to 0.25 microgram/ml. The cerebrospinal fluid (CSF) concentrations of cefotaxime ranged from 5.0 to 15.2 micrograms/ml, and the CSF bactericidal titers were 1:64 to 1:128. The CSF in all patients was sterilized within 96 hours. All 12 patients recovered, and there were no relapses.