Frequency of antiseptic resistance genes in clinical staphycocci and enterococci isolates in Turkey.

Background: Disinfectants and antiseptics are biocides widely used in hospitals to prevent spread of pathogens. It has been reported that antiseptic resistance genes, 's, caused tolerance to a variety of biocidal agents, such as benzalkonium chloride (BAC) and chlorhexidine digluconate (CHDG) in . isolates. We aimed to search the frequency of antiseptic resistance genes in clinical and . isolates to investigate the possible association with antiseptic tolerance and antibiotic resistance.

Methods: Antiseptic resistance genes (, , , , and isolated from Gram-positive cocci (69 . and 69 .) were analyzed by PCR method. The minimum inhibitory concentrations (MICs) of BAC and CHDG were determined by agar dilution method, whereas antibiotic susceptibility was analyzed by disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI) criteria.

Results: The frequency of antiseptic resistance genes was found to be high (49/69; 71.0%) in our clinical staphylococci isolates but absent (0/69; 0%) in enterococci isolates. The frequency of and genes was higher (25/40; 62.5% and 7/40; 17.5%, respectively) in coagulase negative staphylococci (CNS) when compared to strains (3/29; 10.3%, and 4/29; 13.8%, respectively). In contrast, the frequency of and genes was higher (11/29; 37.9% and 8/29; 27.5%, respectively) in than those of CNS (5/40; 12.5%, 10/40; 25.0%) strains. was not identified in none of the strains. We found an association between presence of antiseptic resistance genes and increased MIC values of BAC (>4 μg/mL) in staphylococci and it was found to be statistically statistically significant ( < 0.01). We also showed that MICs of BAC and CHDG of vancomycin-resistant enterococci (VRE) isolates were significantly higher than those of vancomycin-susceptible enterococci (VSE) isolates ( < 0.01).

Conclusions: For our knowledge, our study is the first to investigate antiseptic resistance genes in enterococci and also , , and genes in staphylococci isolates in Turkey. Further studies are needed to revise the biocide policy and to support infection control programs to avoid the development of new resistance mechanisms.