Telithromycin susceptibility and genomic diversity of macrolide-resistant serotype III group B streptococci isolated in perinatal infections

Abstract

We studied the telithromycin, erythromycin, azithromycin, and clindamycin susceptibilities of serotype III macrolide-resistant group B streptococci, together with genetic mechanisms of resistance and genomic diversity. ermB, ermA, and mefA were found in, respectively, 57, 32, and 9% of isolates. The telithromycin MIC at which 90% of isolates were inhibited was 0.5 micro g/ml. Macrolide resistance was associated with dissemination of resistance determinants among isolates of different genetic backgrounds.