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Background and Objective: Methicillin-resistant Staphylococcus aureus is a common pathogen responsible for health-care-related infections. This study was done to determine the prevalence of Meticilin - resistant Staphylococcus isolated from hand and nasal of hospital health worker. Methods: This descriptive study was conducted on 148 health workers in teaching hospitals in Sari, northern Iran during 2011-12. Samples were collected from fingers and noses and were cultured on mannitol salt agar immediately. Suspected colonies were identified using Gram staining, catalase and coagulase tests. Susceptibility testing was performed by disk diffusion method. Methicillin resistant strains were determined using micro dilution broth method. Results: Staphylococcus aureus was observed in 24 (16.2%) of individuals. 9.5% of population was resistant to Methicillin. The high portions of Staphylococcus aureus carreier were in the operation room, angiography and internal pediatric ward health worker. Methicillin Staphylococcus aureus resistanat were more common in nasal samples of the operation room personal and angiography ward health worker. All strains were sensitive to Vancomycin and Chloramphenicol and resistant to Penicillin and Amoxicillin. Conclusion: In this study the prevalence of the Staphylococcus.aureus in teaching hospitals health worker was low while Staphylococcus aureus resistant to methicillin was higher than other reports in Iran.

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Background and Objective: Beta-lactamase enzymes are the most important resistance factors among Gram-negative bacteria to the beta-lactam group of antibiotics. This study was conducted to determine the prevalence of extended-spectrum beta-lactamases (ESBL) in Escherichia coli isolates using PCR method.

Methods: This descriptive – analytic study was conducted on 120 Escherichia coli samples isolated in hospitals in Sari in northern Iran during 2013. Antibiogram was conducted using combined disk method to determine the sample resistance. The presence of β- lactamase gene of CTX-M-15 in ESBL was assessed using PCR method.

Results: Out of 120 Escherichia coli, 98 (81.6%), 15 (12.5%) and 7 (5.8%) bacteria isolated from urinary tract, blood and wound, respectively. Multiple drug resistance were seen in 98% of urine samples, 12.7% of blood samples and 3.6% of wound samples (P<0.05). 18.3% of multiple drug resistance samples were positive for CTX-M-15 β -lactamases resistance gene. The probable presence of CTX-M-15 were detected in blood sample (20%), urine sample and wounds (14.3%) (P<0.05).

Conclusion: Beta-lactamase enzymes were detected in high percent of Escherichia coli isolated from urine samples.