Prevalence and patterns of resistance of Streptococcus pneumoniae strains isolated from carriers attending day care centers in the area of Athens

The prevalence and patterns of Streptococcus pneumoniae resistance to antib iotics was examined in 146 nasopharyngeal carrier strains obtained during A pril and May, 1997, from 382 healthy children attending eight day care cent ers (DCCs) in the area of Athens. Reduced susceptibility to at least one an tibiotic was found in 32.6% as follows: penicillin 11.4% (intermediate), ce fotaxime 0.8% (intermediate), trimethoprimsulfamethoxazole 22.7%, erythromy cin 13.6%, tetracycline 11.4%, chloramphenicol 8.3%, Most of the nonsuscept ible to penicillin isolates belonged to serogroups 23, 9, and 19, Multidrug resistance was detected in 11.4% of S, pneumoniae isolates including five penicillin nonsusceptible serogroup 23 strains. More than half of the multi drug resistant strains were susceptible to penicillin and belonged to serog roups 6 (4), 23 (1), 19 (1), and 1(1), Strains that belonged to the same se rogroup/serotype and had identical resistance patterns appeared to cluster in some DCCs. Antibiotic use in the previous month was associated with redu ced susceptibility to penicillin (p = 0.007) and multidrug resistance (p = 0.012). In conclusion, a moderate prevalence of reduced susceptibility to p enicillin in pneumococcal carrier strains was found in our community. Multi drug resistance was common and was often associated with susceptibility to penicillin. Several distinct patterns of resistance were observed, suggesti ng the spread of resistant clones to our country.