The coa, mec, and spa genes diversity among methicillin-resistant Staphylococcus aureus Strains from health-care workers and patients

Abstract

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen that is frequently isolated in both hospital and community environments. MRSA is considered a major nosocomial pathogen that causes severe morbidity and mortality. Materials and Methods: Two hundred and twenty-five nasal swabs were collected (100 from health-care workers and 125 from patients). S. aureus was identified by colony morphology in both blood and mannitol salt agars, catalase and coagulase productions, and also by standard biochemical tests. Susceptibility test to several antimicrobial agents was performed by disc diffusion agar according to the Clinical and Laboratory Standards Institute guidelines. The polymerase chain reaction amplification of the coa, mecA, and spa gene was carried out in the clinical isolates showed resistant to oxacillin. Results: Among 225 isolates of bacteria, 76 were confirmed to be S. aureus by phenotypic characteristics. Thirty isolates were considered MRSA by susceptibility antimicrobial test. Twenty-four were confirmed to be S. aureus by the presence of coa gene bands. Twenty-one S. aureus isolates were confirmed to be MRSA by the presence of mecA gene. The spa gene in health-care workers was present in 88.88% and for patients was 41.66%. Conclusions: This study is suggestive that the PCR for the detection of coa, mecA, and spa gene is a fast, accurate, and valuable diagnostic tool.