Antibiotic Resistance Patterns and Virulence Determinants of Different SCCmec and Pulsotypes of Staphylococcus Aureus Isolated from a Major Hospital in Ilam, Iran

Abstract

Aims & Objectives:The aim of this studyisto evaluate genetic relatedness, antibiotic resistance pattern, and virulence characteristics of different types ofS. aureusisolated from air, surfaces, staff, and patients in a Public hospital in Ilam.Methods & Materials:A total of 88 of 140 staphylococci identified asS. aureusby conventional and molecular methods were used in this study. Isolate samples were obtained from surfaces, staff, patients, and hospital indoor air. The sampling from staff and surfaces was done through using swab and air by standard pump. Antimicrobial susceptibility testing and presence different resistant and virulence determinants was assessed. Isolates were then typed by pulsed-field gel electrophoresis (PFGE) and SCCmectyping methods.Results:Out of 88isolates, 36 of them (40.9%) were MRSA. Among MRSA isolates, the range of resistance to antibiotic was 0% in vancomycin to 83.3% in gentamycin. The most prevalent resistant genes among gentamicin resistantS. aureuswereacc (6')/aph (2”)Iaandaph(3”)IIIa. The most common erythromycin resistant gene wasermC. Surprisingly, SCCmectypes I (30.5%), II (25%)were highly distributed. PFGE analysis showed 33 different pulsotypes.Conclusion:This study confirms that different isolates of MSSA and MRSA circulate in Ilam which differ in antimicrobial susceptibility, content of resistance, and virulence determinants.