وامل خطرمرتبط با حاملين استافيلوكوك اورئوس مقاوم به متي سيلين در بيني و تعيين الگوي حساسيت آنتي بيوتيكي آن در كاركنان بيمارستان نمازي دانشگاه علوم پزشكي شيراز - 1385

Risk FactorsofNasal Carriage of Methicillin-Resistant Staphylococcus Aureus and its Antibiotic Susceptibility Pattern in Namazi hospitalHealthcareWorkers in Shiraz,Iran

Background & Aims: Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen worldwide. The aim of this studywas to determine the risk factors of nasal carriage of MRSA and itsantibiotic susceptibility pattern among healthcare workersat Namazi Hospital (Shiraz-lran). Methods: In a cross-sectional study from July to November 2006, nasal swabs were taken from 600 stratified randomly selected health care workers. The isolates were identified as S aureus based on morphology, gram stains, catalase test, coauglase test and DNase Agar. To differentiate Methicillinsusceptible S aureus (MSSA) and Methicillin Resistant S aureus (MRSA), agar screen platewas used. All methicillin-resistant isolates were examined for mecA genes existence by PeR performance, The sensitivity patterns of Saureus isolates weredetermined by disc diffusion and E-testmethod. Results: Nasal screening identified 186 (31%) S. aureus carriers of whom, 154 ones (82.8%) were MSSA and 32 ones (17.2%) were MRSA. There was no significant association between related risk factors and gender, age, years of healthcare service and level of education. In the univariate analysis, a statistically significant difference was found only basedon occupation (P=O.032) between carriersofMSSA and MRSA. In multivariate analysis(logistic regression), having nursing occupation (p=D.012, OR=3.6, 95ʹ%CI=1.3-9.7) was independently associated withMRSAcarriage. All of the MRSAstrainswere sensitiveto mupirocin. Conclusion: This study revealed that having nursing occupation is independently associated with MRSA carriage since all S.aureus isolates were susceptible to mupirocin, topical mupirocin could be used successfully to eradicate nasal staphylococcal colonization and carriers.