Antibiotic Resistance Pattern of Isolated Strains of Staphylococcus Aureus from Personnel Nasal Specimens in Meshgin Shahr Valiasr Hospita

Staphylococcus aureus is known as an important pathogen causing a variety of bacterial infections. Treatment of this bacterium with antibiotics has led to antibiotic-resistancy, especially against methicillin (MRSA) and more recently rare resistance against vancomycin. The aims of this study were to determine nasal carriage rates of S. aureus in Meshgin Shahr Valiasr hospital's personnel and to determine antibiotic-resistance patterns in the mentioned isolates. Staphylococcus aureus isolates were collected from the nose of 200 hospital personnel in Meshgin Shahr Valiasr hospital in a 2 month period in 2006. Antibiotic sensitivity of the collected strains were tested against antibiotics used in routine treatment of S. aureus infections. Oxacillin agar was also used to screen for MRSA according to NCCLS recommendation. Our results showed there were 45% and 16% nasal carrier for S. aureus and MRSA (methicillin resistant staphylococcus aureus) strains, respectively in hospital personnel. Thirty two isolates were able to grow in oxacillin agar media, indicating 35% MRSA strains. Antibiotic resistant pattern of strains in disk method were as follows: 35% to oxacillin, 97.8% to penicillin, 34% to erythromycin, 2.1% to chloramphenicol, 39.36% to tetracycline, 11.7% to gentamicin, 30.85% to trimetohoprim sulfamethoxazol and 19% to clindamycin. All of the isolates were sensitive to vancomycin and ciprofloxacin. In this study, nasal carriage rate of Staphylococcus aureus among hospital Personnel was more than community expected rate (%40) and lower than hospital expected rate (%50-80). All of the test strains were sensitive to Vancomycin.