Resistance to Tetracycline and Vancomycin of Staphylococcus aureus Isolates from Sanandaj Patients by Molecular Genotyping

Abstract

Introduction: Studying antibiotic resistance of Staphylococcus aureus is very important and it has a main role in preventing creation of resistant strains. This study was done to determine the prevalence and genetic basis of tetracycline and vancomycin resistance in Staphylococcus aureus in Sanandaj. Materials and methods: One hundred and fifty clinical isolates of Staphylococcus aureus were collected from Sanandaj Hospital. Susceptibility to antibiotics (tetracycline and vancomycin) were determined by disk agar diffusion method with minimal inhibitory concentration (MIC) evaluated on Muller-Hinton agar as described by the Clinical and Laboratory Standards Institute (CLSI). The tetracycline and vancomycin strains were screened by polymerase chain reaction (PCR) for the presence of five common vancomycin and tetracycline resistance determinants, respectively, van A, tet K, tet M, tet L and tet O. Results: Using the DAD method, 12% of the Staphylococcus aureus isolates were resistant to vancomycin and 61/33% to tetracycline. For more, the tet (K) gene was found in 71 isolates, tet (L) in 5 isolates, tet (M) in 30 isolates and tet (O) were detected in one isolates and van A didn’t see in any isolate by PCR technique. Conclusion: This study indicates that resistance to tetracycline is mainly by efflux pumps mediated by tet (K) in Staphylococcus aureus in Sanandaj.