title: Prevalence of macrolide-resistance genes in Staphylococcus aureus and Enterococcus faecium isolates from 24 European university hospitals.
abstract: The polymerase chain reaction (PCR) was used to study the prevalence of the macrolide resistance genes ermA, ermB, ermC, msrA/msrB, ereA and ereB, in 851 clinical isolates of Staphylococcus aureus and 75 clinical isolates of Enterococcus faecium that were erythromycin resistant. The isolates were from 24 European university hospitals. In S. aureus, the ermA gene was more common in methicillin-resistant S. aureus (MRSA) isolates (88%) than in methicillin-susceptible S. aureus (MSSA) isolates (38%), and occurred mainly in strains with constitutive MLS(B) expression. In contrast, ermC was more common in MSSA (47%) than in MRSA (5%), occurring mainly in strains with inducible expression. The ereB gene was only found in MRSA isolates expressing a constitutive MLS(B) phenotype (1%). The ereA gene was not detected. Macrolide resistance by efflux due to the msrA/msrB gene was only detected in MSSA isolates (13%). In contrast to S. aureus, erythromycin resistance in E. faecium was almost exclusively due to the presence of the ermB gene (93%).
authors.affiliation: Institute for Medical Microbiology and Virology, Heinrich-Heine Universität Düsseldorf, Universitätsstrabetae 1, Geb. 22.21, 40225 Düsseldorf, Germany. schmitfj@uni-duesseldorf.de
authors.forename: F J
authors.initials: FJ
authors.lastname: Schmitz
authors.forename: R
authors.initials: R
authors.lastname: Sadurski
authors.forename: A
authors.initials: A
authors.lastname: Kray
authors.forename: M
authors.initials: M
authors.lastname: Boos
authors.forename: R
authors.initials: R
authors.lastname: Geisel
authors.forename: K
authors.initials: K
authors.lastname: Köhrer
authors.forename: J
authors.initials: J
authors.lastname: Verhoef
authors.forename: A C
authors.initials: AC
authors.lastname: Fluit
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003428:Cross Infection / Q000382:microbiology; D017931:DNA Primers; D004352:Drug Resistance, Microbial; D016984:Enterococcus faecium / Q000187:drug effects* / Q000235:genetics*; D004917:Erythromycin / Q000494:pharmacology; D005060:Europe / Q000453:epidemiology; D005798:Genes, Bacterial / Q000235:genetics*; D016680:Genome, Bacterial; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D006785:Hospitals, University; D006801:Humans; D016133:Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D017931:DNA Primers; D004917:Erythromycin