Antibiotic resistance pattern of Methicillin-resistant Staphylococcus aureus isolated from hospitalized patients

Methicillin-resistant S. aureus (MRSA) strains circulating among populations and crossing borders constitute a major problem for health control and require a fast and simple genotypic approach. The objective of this study was to determine the prevalence, molecular types and drug resistance pattern of S. aureus isolated from Hospitalized Patients in teaching Hospitals of Ahvaz. this cross-sectional study was from April to September 2023, MRSA strains were identified by phenotypic and molecular methods. The antibiotics studied were), Cefoxitin (15 μg) Gentamicin (10 μg), Ciprofloxacin (5 μg), Erythromycin (15 μg), Clindamycin (2 μg), linzolide(10μg), azithromycin(5 μg). The tests were performed according to the guidelines of clinical and Laboratory Standards Institute (CLSI). It also detected the mecA gene of Methicillin-resistant S. aureus strains (MRSA). 470 Staphylococcus aureus samples from patients hospitalized in different departments of Ahvaz Hospitals included 283 blood culture samples, 75 wound samples, 72 body fluid samples and 40 catheter samples, and 321 (68.3%) MRSA isolates were reported. All these 321 MRSA isolates were tested with ampicillin, ciprofloxacin, clindamycin, linezolid, gentamicin, erythromycin, and azithromycin antibiotics. Also, the results of molecular identification of the mec A gene in 321 strains of S. aureus showed that 312 strains carry the mec A gene. The high prevalence of S. aureus samples can be caused by long-term hospitalization of patients in the ward and excessive use of antibiotics to treat the infection and increased resistance in isolates. As a result, more monitoring of the hospital's infection control department, as well as the expansion of the correct use of antibiotics, seems necessary and important.