Klinik Kaogülaz Negatif Stafilokok Kökenlerinin Antibiyotik Duyarlılıklarının ve Bazı Virülans Faktörlerinin Araştırılması
Project no. 265 · Status: Kapanmış · 2017
Summary
Investigation of Antibiotic Susceptibilities and Some Virulance Factors of Clinical Coagulase Negative Staphylococcus Isolates Although Coagulase Negative Staphylococci (CoNS) species are among the microbiota members on the skin and mucosal surfaces, they cause infections especially related to medical devices such as catheters. Biofilm formation and resistance to many antibiotics make it difficult to treat the infections they cause. Nowadays, antibiotic resistance is an important social health problem and the right antibiotic selection is of great importance in the treatment of bloodstream infections, which are frequently caused by CoNS species. The aim of this study was to investigate the resistance profile to various antibiotics and some virulence related genes of catheter related clinical CoNS isolates. In our study, 43 CoNS strains isolated from patients hospitalized in Manisa Celal Bayar University Hospital were evaluated for their susceptibility to ampicillin, clindamycin, mupirocin, linezolid, tigecycline, tetracycline, cefotaxime, gentamicin, vancomycin, ciprofloxacin, erythromycin and fusidic acid antibiotics. The presence of clonal relationships and some virulence factors were also investigated. Susceptibilities of cefoxitin and other antibiotics in these strains were determined by disk diffusion and microdilution method, respectively. AacA-aphD and aphA3 for aminoglycoside resistance, mecA and mecC for methicillin resistance, tetK and tetM for tetracycline resistance, ermA, ermB, ermC, msrA for macrolide-lincosamide-streptogramin (MLS) type B resistance, icaA, IS256, nucA and sasX genes, which are important for virulence, were investigated by polymerase chain reaction (PCR). Clonal relationships at species level were examined by Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR. When we consider all our CoNS isolates, the highest and the lowest resistance rates were observed for ampicilin (%93) and linezolid (%2), respectively. There wasn’t any resistant CoNS isolate to tigecycline and vancomycin. It was determined that the CoNS species, whose clonal relationships were examined, were generally belonged to different clones. Also we detected the existence of mecA, aacA-aphD, aphA3, ermB, ermC, msrA antibiotic resistance genes and icaA, IS256 and sasX virulance factor genes. The results of our study revealed that the examined catheter related clinical CoNS isolates had acquired resistance to commonly used antibiotics and that these strains harboring various virulence genes. Therefore, those isolates and their infections should be carefully monitored.