ABSTRACT
Objective: To evaluated the PCR for mecA gene compared with the conventional oxacillin disk diffusion method for methicillin-resistant Staphylococcus aureus (S. aureus) identification. Methods: A total of 292 S. aureus strains were isolated from various clinical specimens obtained from hospitalized patients. Susceptibility test to several antimicrobial agents was performed by disk diffusion agar according to Clinical and Laboratory Standards Institute guidelines. The PCR amplification of the mecA gene was carried out in all the clinical isolates.Results:activity and vancomycin was the most effective. The rate of methicillin-resistant S. aureus prevalence determined by oxacillin disk diffusion method was 47.6%; whereas, 45.1% of S. aureus isolates were mecA- positive in the PCR assay. Among antibiotics used in our study, penicillin showed the least anti-staphylococcal Conclusions: This study is suggestive that the PCR for detection of mecA gene is a fast, accurate and valuable diagnostic tool, particularly in hospitals in areas where methicillin-resistant S. aureus is endemic.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluated the PCR for mecA gene compared with the conventional oxacillin disk diffusion method for methicillin-resistant Staphylococcus aureus (S. aureus) identification.</p><p><b>METHODS</b>A total of 292 S. aureus strains were isolated from various clinical specimens obtained from hospitalized patients. Susceptibility test to several antimicrobial agents was performed by disk diffusion agar according to Clinical and Laboratory Standards Institute guidelines. The PCR amplification of the mecA gene was carried out in all the clinical isolates.</p><p><b>RESULTS</b>Among antibiotics used in our study, penicillin showed the least anti-staphylococcal activity and vancomycin was the most effective. The rate of methicillin-resistant S. aureus prevalence determined by oxacillin disk diffusion method was 47.6%; whereas, 45.1% of S. aureus isolates were mecA- positive in the PCR assay.</p><p><b>CONCLUSIONS</b>This study is suggestive that the PCR for detection of mecA gene is a fast, accurate and valuable diagnostic tool, particularly in hospitals in areas where methicillin-resistant S. aureus is endemic.</p>
ABSTRACT
BACKGROUND: In recent decades, because of increasing prevalence of immunocompromised disease, non-tuberculous mycobacteria that have been known already as environmental bacteria presented as an important pathogens. In this study, the prevalence of NTM in Isfahan city water samples was determined bydifferent methods including culture methods with biochemical tests. MATERIALS AND METHODS: Eighty-five water samples were collected from different sources in Isfahan, Iran. The mycobacterial isolates were identified by the growth characteristics, pigment production, semi-quantitative catalase test, Tween 80 hydrolysis, arylsulfatase test (3 and 14 days), heat-stable catalase (pH 7, 68°C), pyrazin amidase (4 and 7 days), urease, nitrate reduction test, and colony morphology. RESULTS: Chlorine concentrations of the samples ranged from 0 to 1.8 mg/l. Twenty-one culturable species including M. fortuitum, 23.8% (5 cases); M.smegmatis, 14.3% (3 cases); M. chelonae like organisms, M. terrae complex, M. gordonae and M. mucogenicum, 9.5% (2 cases for each species); M. avium complex, M.phlei, M. xenopi, M. fallax, and M. flavescenc 4.8% (1 case for each species) were identified. CONCLUSION: The results of this study showed the incidence of different species of NTM in this geographical region in Iran. Studies show that the prevalence of immunocompromised disease is increasing in the community and it needs different treatment management strategy; therefore, the results of this study can be useful in this strategy.
ABSTRACT
The majority of Staphylococcus aureus infections from Isfahan, Iran, were caused by epidemic methicillin-susceptible S. aureus (MSSA) lineages, sequence type 8 (ST8), ST22, ST30, and ST6. The predominant methicillin-resistant S. aureus strain was ST239. We observed a high prevalence of Panton-Valentine leukocidin-positive MSSA strains (19.7%), which is a matter of considerable concern, since these strains have the ability to cause severe infections.
