Gram-negative bacillary meningitis in Egypt

Abstract

Gram-negative bacillary meningitis (GNBM) is a rare disease with a high rate of mortality. The aim of this study was to describe the clinical presentation and outcome of primary and secondary GNBM and to evaluate the efficacy of ceftriaxone (a third-generation cephalosporin) in the treatment of this disease. A retrospective study was conducted including 95 patients with GNBM admitted to the Abbassia and Imbaba fever hospitals' meningitis wards in Egypt during the period from 1993 to the end of the year 2009. Their cerebrospinal fluid samples were subjected to conventional bacteriological methods for isolation of the causative Gram-negative bacilli. Forty-nine patients had primary GNBM (no predisposing cause of meningitis was detected) and 46 patients had secondary GNBM (with a predisposing cause of meningitis). Primary GNBM was characterized by an abrupt onset and was significantly associated with typical signs of meningeal irritation. The most common infecting organisms were Salmonella typhi in 16 (33%) patients and Escherichia coli in 15 (31%) patients. Of the patients with primary GNBM, 26 (53%) were cured, 11 (22%) developed neurological sequalae, and 12 (24%) patients died. Secondary GNBM was characterized by an insidious onset and significantly associated with unarousable coma. The most common infecting organisms were Proteus mirabilis in 17 (37%) patients and Pseudomonas aeruginosa in 16 (35%) patients. The most common predisposing factor of meningitis was otitis media and occurred in 26 (57%) patients. Of the patients with secondary GNBM, 15 (33%) were cured, 15 (33%) developed neurological sequalae, and 16 (35%) died. Primary GNBM was significantly associated with a higher cure rate than secondary GNBM. The duration of symptoms in patients with secondary GNBM was significantly higher than in those with primary GNBM. Ceftriaxone was the initial drug for treatment of these patients until the antibiotic sensitivity tests were reported. The overall resistance rate to the drug was 4%. GNBM still has a high mortality rate and should be managed as a medical emergency. GNBM should be suspected in patients with otitis media, neurosurgical, and head trauma or who underwent spinal anesthesia and have disturbance in their level of consciousness, even if there are no signs of meningeal irritation. Ceftriaxone is still an effective drug and had a low rate of resistance in our study.