The prognostic factors of adult gram-negative bacillary meningitis

Seventy-seven patients with Gram-negative bacillary meningitis (GNBM), 57 males and 20 females, aged 17-86 years, were identified at Kaohsiung Chang Gung Memorial Hospital, over an 11-year period. Fifty-four infections were community-acquired, and 23 were nosocomial; 49 were spontaneous and 28 occurred after head surgery or neurosurgery. The organisms most frequently involved were Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Acinetobacter. Rarer pathogens included Citrobacter species, Serratia marcescens, Enterobacter cloacae, and Proteus mirabilis. All patients who did not receive appropriate antibiotic therapy died. The mortality in those treated with appropriate antibiotics was 28%. Other statistically significant prognostic factors included septic shock, initial level of consciousness, hyperosmolar hyperglycemic nonketotic coma, disseminated intravascular coagulation, high cerebrospinal fluid lactate levels and leucocytosis. In the multiple logistic regression analysis, only appropriate antimicrobial therapy and septic shock were strongly associated with mortality even after adjusting for other potentially confounding factors. Despite the high mortality, management can be improved by early diagnosis, early use of appropriate antibiotics, and correction of underlying and associated medical derangement.