The frequency of qacA/B and smr genes in clinical isolates of methicillin resistance coagulase negative staphylococci

Increasing use of disinfectants biocide cause to appearance of resistant strains of coagulase negative Staphylococcus. Some research confirmed this gene responsible for resistance to methicillin and association with these agents. The aim of this study was to investigate the presence of resistance genes of biocides such as qac A/B and smr in coagulase negative staphylococci. Materials & Methods: In this cross-sectional study, 60 samples of Staphylococcus epidermidis and 49 samples of Staphylococcus saprophyticus were collected over 9 months from clinical samples. After the initial biochemical tests and confirmation of genus and species of isolates, specific primers were used to study aqcA/B and smr genes through polymerase chain reaction (PCR). Data were analyzed using chisquare test. Results: Of 60 isolates of Staphylococcus saprophyticus, 36 isolates (60%) had mecA. Among these, 19 isolates (52.77%) had qacA and 21 isolates (58.33%) had smr. Furthermore, of 49 Staphylococcus epidermidis isolates, 27 isolates (55.1%) had mecA and among those isolates, 11 isolates (22.44%) had qac A/B and 8 isolate (16.32%) had smr. Conclusions: The results of our study showed the widespread presence of qac A/B and smr in clinical isolates of methicillin-resistant coagulase-negative staphylococci. Given the low frequency of qacA/B and smr in the isolates sensitive to the antibiotics, it is necessary to evaluate antibiotic resistance for treatment of microbial infections.