title: Macrolide-lincosamide-streptogramin B resistant phenotypes and genotypes for methicillin-resistant Staphylococcus aureus in Turkey, from 2003 to 2006.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) strains with inducible macrolide-lincosamide-streptogramin B (iMLS(B)) resistance phenotype may lead to clinical failure during clindamycin (CLI) therapy. The aim of this study was to determine the incidence of MLS(B) phenotypes by using D-test method and genotypes by using multiplex real-time PCR method in MRSA strains. A total of 265 MRSA strains were obtained from clinical samples from hospitalized and outpatients. Of the MRSA isolates, 225 (84.9%) were resistant to erythromycin (ERT), and 170 (64.1%) to CLI. Among the 225 ERT-resistant MRSA strains, the constitutive MLS(B) (cMLS(B)) rate was found in 49.3%, iMLS(B) in 39.1% and the M phenotype in 11.5%. Overall, ermA, ermC, ermA+ermC, msrA, ermC+msrA, and ermA+ermC+msrA genes were detected in 85 (37.7%), 60 (26.6%), 42 (18.6%), 26 (11.5%), 11 (4.8%), and 1 (0.4%) isolates, respectively. Most prevalent resistance determinant in MRSA strains was ermA, which was detected in 37.7% of the isolates. The 26 MRSA strains with M phenotype harboured only msrA gene. In conclusion, due to aware of the potential of CLI treatment failure, D-test should be performed and reported in MRSA strains in clinical laboratories. The multiplex real-time PCR method is easy to perform, fast and reliable method for the detection of MLS(B) resistance genotypes.
authors.affiliation: Department of Infectious Diseases, Gulhane Military Medical Academy and School of Medicine, 06018 Etlik, Ankara, Turkey.
authors.forename: H Cem
authors.initials: HC
authors.lastname: Gul
authors.forename: Abdullah
authors.initials: A
authors.lastname: Kilic
authors.forename: Aylin Uskudar
authors.initials: AU
authors.lastname: Guclu
authors.forename: Orhan
authors.initials: O
authors.lastname: Bedir
authors.forename: Mustafa
authors.initials: M
authors.lastname: Orhon
authors.forename: A Celal
authors.initials: AC
authors.lastname: Basustaoglu
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D002648:Child; D002981:Clindamycin / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial; D004917:Erythromycin / Q000494:pharmacology; D005260:Female; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D055231:Lincosamides / Q000494:pharmacology; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics*; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D016133:Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology*; D025381:Streptogramin B / Q000494:pharmacology; D014421:Turkey
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D055231:Lincosamides; D026901:Membrane Transport Proteins; C066202:msrA protein, Staphylococcus epidermidis; D025381:Streptogramin B; D002981:Clindamycin; D004917:Erythromycin; D008780:Methyltransferases; C431709:ErmA protein, Bacteria; C035181:rRNA (adenosine-O-2'-)methyltransferase