[Epidemiology of acute bacterial meningitis in adult patients in France]. / Actualisation de l'épidémiologie des méningites bactériennes aiguës chez l'adulte en France.

ABSTRACT

In 2006, the number of bacterial meningitis cases was estimated at 1375 (2.23/100,000). The leading pathogens involved in adult meningitis were, according to frequency, Streptococcus pneumoniae, Neisseria meningitidis, Listeria monocytogenes, Streptococcus agalactiae, and Haemophilus influenzae. The overall mortality rate averaged 20%, higher among patients with pneumococcal meningitis or in individuals over 65 years of age. Sequels were observed in 30% of cases and more frequent after pneumococcal meningitis. A decrease in susceptibility to antibiotics was reported for N. meningitidis, S. pneumoniae and H. influenzae. Generalized vaccination of children less than two years of age with H. influenzae type b conjugate vaccine has lead to a dramatic decrease in adult H. influenza meningitis. The few cases involved almost exclusively non-typeable strains, presenting in 12% of cases, a modified penicillin binding protein leading to a decreased susceptibility to aminopenicillins. Decreased susceptibility to amoxicillin was observed in 30% of meningococcal isolates, but all strains remained susceptible to parenteral third generation cephalosporins. Resistances to rifampicin or to ciprofloxacin, recommended in meningococcal meningitis prophylaxis, were unusual, but had to be documented. Finally, the proportion of pneumococcal strains with decreased susceptibility to beta-lactams has decreased since 2002. In adult meningitis, pneumococcal isolates with decreased susceptibility to penicillin, amoxicillin, and cefotaxime or ceftriaxone accounted for 37, 18, and 4% of cases respectively. It should be noted that for these isolates, no parenteral third generation cephalosporins MIC was above 2mg/l. Resistance to rifampin was very unusual and all pneumococcal isolates were fully susceptible to glycopeptides.