Macrolide-lincosamide-streptogramin B resistant phenotypes and genotypes for methicillin-resistant Staphylococcus aureus in Turkey, from 2003 to 2006

Pol J Microbiol. 2008;57(4):307-12.

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.

MeSH terms

  • Adult
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics
  • Child
  • Clindamycin / pharmacology
  • Drug Resistance, Multiple, Bacterial*
  • Erythromycin / pharmacology
  • Female
  • Genes, Bacterial*
  • Genotype
  • Humans
  • Lincosamides / pharmacology
  • Male
  • Membrane Transport Proteins / genetics
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Methicillin-Resistant Staphylococcus aureus / genetics*
  • Methyltransferases / genetics
  • Microbial Sensitivity Tests
  • Phenotype
  • Polymerase Chain Reaction
  • Staphylococcal Infections / drug therapy*
  • Staphylococcal Infections / microbiology*
  • Streptogramin B / pharmacology
  • Turkey

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Lincosamides
  • Membrane Transport Proteins
  • msrA protein, Staphylococcus epidermidis
  • Streptogramin B
  • Clindamycin
  • Erythromycin
  • Methyltransferases
  • ErmA protein, Bacteria
  • rRNA (adenosine-O-2'-)methyltransferase