[Acquired bacterial meningitis in Monastir region, Tunisia (1999-2006): bacteriological aspects and susceptibility patterns]

Abstract

The aim of this study was to analyze the distribution of bacteria responsible for purulent meningitis and the pattern of resistance of common species in the University Hospital of Monastir (Tunisia). All bacteriologically confirmed cases of bacterial meningitis were recorded between 1999 and 2006, and have been analyzed by classic bacterial methods advocate for meningitis. Two hundred fifty three strains have been isolated. The most frequent species were Streptococcus pneumoniae, Haemophilus influenzae, and Klebsiella pneumoniae, followed by Escherichia coli and Neisseria meningitides with 19.4, 13.8, 13.8, 7.1, and 6.3% of cases, respectively. Their distribution with regard to age was in accordance with literature data. The yearly distribution of these bacteria did not show any epidemic peak. Enterobacteriaceae and group B Streptococcus were the most frequently identified pathogens in neonatal meningitis. H. Influenzae was the predominant microorganism in children between three month and five years of age (36.3%), followed by S. Pneumoniae (28.8%). S. Pneumoniae was the predominant bacteria responsible for 47% of the cases over five years of age. 38.8% of S. Pneumoniae strains were less susceptible to penicillin. Resistance rates for amoxicillin and cefotaxime were 4.1%, respectively. Only one strain of N. meningitidis (6.2%) presented a decreased susceptibility to penicillin. 22.9% of H. Influenzae strains produced β-lactamase. The resistance rates of Enterobacteriaceae to third generation cephalosporins were 25%. In our study, nosocomial meningitis have shown a rate of 24.4%. The most affected service was neurosurgery, pediatrics, and intensive care units. The increasing prevalence of pneumococci meningitis with reduced sensitivity to penicillin G strains isolated from meningitis makes adequate therapeutic management difficult.