In vitro activities of the oxazolidinone compounds linezolid (PNU-100766) and eperzolid (PNU-100592) against middle ear isolates of Streptococcus pneumoniae

Abstract

Two hundred and sixteen isolates of Streptococcus pneumoniae recovered between 1994 and 1996 from the middle ears of children with acute otitis media were tested for their susceptibility to penicillin, erythromycin, clindamycin and the oxazolidinones, linezolid (PNU-100766) and eperezolid (PNU-100592). There were 116 isolates from the Children’s Hospital of Pittsburgh and 100 isolates from a national collection. Eighty percent of the local strains were susceptible to penicillin (MIC<0.1 mg/l); 20% of the local strains and all of the national strains had reduced susceptibility to penicillin. All strains of S. pneumoniae tested had an MIC<2.0 mg/l for both oxazolidinones. A regional difference was noted in the frequency of resistance to erythromycin with local isolates being more susceptible than isolates from the national collection. This difference was most pronounced among the high-level penicillin-resistant strains of S. pneumoniae.