Gram-negative enteric bacillary meningitis: a twenty-one-year experience.

We reviewed our experience with gram-negative enteric bacillary meningitis in neonates and infants from 1969 through 1989. Ninety-eight patients were identified. Their ages were from 1 day to 2 years with a median of 10 days. In 25 patients (26%), predisposing factors were identified, the most common of which were neural tube defects and urinary tract anomalies. The causative agents were Escherichia coli (53%), Klebsiella-Enterobacter species (16%), Citrobacter diversus (9%), Salmonella species (9%), Proteus mirabilis (4%), Serratia marcescens (3%), Bacteroides fragilis (3%), and Aeromonas species (2%). At the time of diagnosis, Gram-stained smears of cerebrospinal fluid revealed gram-negative bacilli in 61% of patients. The causative organism was cultured from blood obtained from 55% of patients, and 21% had positive urine culture results. The cerebrospinal fluid leukocyte counts ranged from 0 to 80,600 cells/mm3, and the cerebrospinal fluid/serum glucose concentration ratio was less than 0.5 in 72% of patients. Antimicrobial regimens varied greatly. After initiation of antibiotic therapy, an average of 3 days was needed for eradication of bacteria from cerebrospinal fluid. The case-fatality rate was 17%, and 61% of survivors had long-term sequelae that included seizure disorders, hydrocephalus, physical disability, developmental delay, and hearing loss.