Epidemiological data on antimicrobial resistance in pneumococcal meningitis

Between 1987 and 1994, 1,023 strains of S. pneumoniae isolated from CSF were sent to the National Reference Center. 185 (18.1%) were penicillin-resistant pneumococci (PRP) and among them 49.7% were strains with high-level resistance to penicillin (MIC >1 mg/l), 58.9% strains with multi-resistance. The annual rate of PRP increased from 5.7% in 1989 to 14.1% in 1991 and 27.1% in 1994 (adults 25.4%, children 36.4%). MIC50/MIC90 of penicillin, amoxycillin, cefotaxime, imipenem, vancomycin, rifampicin, on 221 strains isolated from CSF during 1994, were: 0.016/2; 0.016/1; 0.016/1; 0.008/0.125; 0.25/0.25; 0.064/0.125. Among 60 PRP isolated from CSF in 1994: 51.7% were strains with high-level resistance to penicillin, 61.7% were cefotaxime (CTX) sensitive, 35% CTX intermediate resistant (MIC=1 mg/l), and 3.3% were resistant to CTX (MIC greater than or equal to 2 mg/l). For the 1,023 strains, the most prevalent serogroups or serotypes were: 23 (14.5%), 6 (10.6%), 14 (9.8%), 9 (7.8%), 19 (7.7%), and for 185 PRP strains: 23 (47%), 9 (22.6%), 15 (8.6%), 14 (7.6%), 6 (7%), 19 (3.8%). Pneumococcal polysaccharide vaccine serogroup coverage (%) of PRP was: 99% for adults (23 valent vaccine) and 95% for children (7 valent vaccine: 4, 6B, 9V, 14, 18C, 19F, 23F). Clinical data was collected for 46 patients between 1987 and 1993 and 47 patients in 1994. During: the first period, 16 CSF cultures remained positive 3 to 12 days after initiation of therapy; initial combination of beta-lactam antibiotics with vancomycin or fosfomycin was not used. During the second period, only 1 CSF culture remained positive at day 9, at this time, initial combination of beta-lactam with other antibiotics was used (n=19) and initial mean dosage of beta-lactams was higher.