Activity of telithromycin compared with seven other agents against 1039 Streptococcus pyogenes pediatric isolates from ten centers in central and eastern Europe.

In total, 1039 pediatric Streptococcus pyogenes isolates from Bulgaria, Croatia, the Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia and Slovenia were studied. All strains were susceptible to penicillin G, levofloxacin, and quinupristin-dalfopristin, 91-100% to telithromycin, and 82-100% to erythromycin, azithromycin, and clarithromycin, and 90-100% to clindamycin. Macrolide resistance occurred mainly in Slovakia (25%), the Czech Republic (17.3%), and Croatia (15.8%). Overall, 9.7% of S. pyogenes isolates were erythromycin resistant due to erm(B)- or erm(A)-encoded methylases (72.3%) or to a mef(A)-encoded efflux pump (25.7%). One strain had alterations of both 23S rRNA (A2058G Escherichia coli numbering) and ribosomal protein L22 (G95D).