The concentration of lactic acid in cerebrospinal fluid (CSF) was determined by gas-liquid chromatography in 205 samples of CSF from 97 patients with or without infections of the central nervous system. Patients without infection or those with nonbacterial (presumably viral) meningitis consistently had low concentrations of lactic acid in CSF (i.e., less than or equal to 35 mg/100 ml), whereas patients with bacterial or tuberculosis meningitis consistently had concentrations of lactic acid in CSF of greater than 35 mg/100 ml. There was no overlap in concentrations of lactic acid between these two groups. Further, lactic acid concentrations in CSF from patients partially treated for meningitis were generally greater than 35 mg/100 ml through the third day of therapy and, thereafter, progressively declined to less than 20 mg/100 ml by the seventh to 10th day of therapy. Relapse of bacterial infection was consistently documented by a recurrence of an increased concentration of lactic acid in CSF. Preliminary experience with determination of the concentration of lactic acid in CSF suggests that it may be useful in distinguishing bacterial (with or without positive cultures) and tuberculous meningitis from meningitis due to nonbacterial causes.

Twelve patients, aged 6 months to 62 years, with proven bacterial meningitis, were given a single intravenous dose of cefamandole (33 mg/kg) 75 to 140 min before a routine lumbar puncture. Infecting organisms included Haemophilus influenzae (eight cases), Streptococcus pneumoniae (two cases), and Neisseria meningitidis and (8-hemolytic streptococcus (one each). Cerebrospinal fluid (CSF) was analyzed by microbiological assay for cefamandole. The median concentration was 0.60 ,ug/ml, ranging from undetectable to 7.4 ,ug/ml. CSF cefamandole concentrations correlated with CSF protein: in six patients with CSF protein less than 100 ,ug/dl, the range of drug concentration was 0 to 0.62

A randomized therapeutic trial of carbenicillin (CB)