Prevalence of Methicillin-resistant Staphylococcus aureus(MRSA) and determination of antibiotic resistance-encoding genesamongst the human clinical infections collected from Isfahan, Iran

Background and Aim : Methicillin-resistant Staphylococcus aureus (MRSA) is an emergingbacterium responsible for severe cases of antibiotic-resistant hospital and nosocomial infections.This survey aimed to evaluate the profile of antibiotic resistance-encoding genes in the MRSAbacteria isolated from different types of human clinical samples.Methods : In the present research, ۳۴ MRSA isolates were collected. MRSA strains were isolatedfrom different types of human clinical samples. Isolates were approved in the laboratory usingmicrobial culture and biochemical tests. MRSA identification was done according to overallresistance toward oxacillin (۱ μg) and cefoxitin (۳۰ μg) antibiotic discs. Polymerase ChainReaction techniques were applied to assess the distribution of antibiotic resistance-encoding genesamongst the DNA samples extracted from MRSA isolates.Results : MRSA distribution amongst the blood, pus, urine, and sputum samples was and ۱۰.۵۲%,۳۱.۵۷%, ۲۶.۳۱%, and ۲۳.۶۸%, respectively. The most commonly detected antibiotic resistanceencodinggenes amongst the MRA isolates were blaZ (۱۰۰%), msrA (۶۸.۴۲%), and tetK (۵۷.۸۹%).However, ermB (۳۱.۵۷%) and aacA-D (۴۲.۱۰%) antibiotic resistance-encoding genes were the lesscommonlky identified antibiotic resistance-encoding genes. Distribution of the ermA and msrBantibiotic resistance-encoding genes were ۵۵.۲۶% and ۳۹.۴۷%, respectively. From a statisticalview, significant differences were shown between the emrA and ermB (P <۰.۰۵), and msrA andmsrB (P <۰.۰۵)Conclusion : Role of MRSA as infectious agent with high antibiotic resistance in an Iranian humanclinical samples was determined. According to high distribution of blaZ (penecillin-encodingresistance gene), msrA (macrolides-encoding resistance gene), and tetK (tetracycline-encodingresistance gene), their prescription should be done with caution.

کلیدواژه ها:

Methicillin-resistant Staphylococcus aureus (MRSA) ، Antibiotic resistance-encodinggenes ، Clinical infections ، Prevalence.