Genotyping of coa and aroA Genes of Methicillin-Resistant Staphylococcus aureus Strains Isolated From Nasal Samples in Western Iran.
BACKGROUND
Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial pathogen frequently isolated in both hospital and community environments. Methicillin-resistant Staphylococcus aureus is considered a major nosocomial pathogen that causes severe morbidity and mortality.


OBJECTIVE
The main objective of this study was to determine the genotypes of MRSA strains isolated from the nares of hospitalized and community patients in Kermanshah Hospital, western Iran, by PCR-restriction fragment length polymorphism (PCR-RFLP).


METHODS
Of 1387 patients, 1217 patients were screened for more than 48 hours after admission in hospital wards and 170 patients were screened in the hemodialysis unit of Kermanshah Hospital, which is the largest hospital in western Iran. S. aureus was identified by standard biochemical tests, including colonial morphology, production of coagulase, and DNase and the API20 Staph test. Methicillin-resistant Staphylococcus aureus was identified by the Oxacillin strip test.


RESULTS
In total, 258 S. aureus isolates were recovered from 1387 samples, of which 96 isolates were MRSA, 82 were hospital acquired, and 14 were community acquired. Digestion of the aro A gene revealed only one distinctive RFLP pattern in the 258 isolates.


CONCLUSIONS
Methicillin-resistant Staphylococcus aureus is an increasingly common cause of nosocomial infections. Our results are in agreement with those of other studies reporting that a few specialized clones are responsible for most cases of MRSA nasal carriage. In this study, MRSA strains isolated from different wards of hospital were closely related when analyzed by coagulase gene typing. Identifying patients colonized with MRSA during hospitalization and rapidly typing them with these methods may facilitate detection of outbreaks and prevention of the spread of organisms in hospitals.
Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, IR Iran.
Parviz
P
Mohajeri
Department of Microbiology, Islamic Azad University, Lahijan Branch, Lahijan, IR Iran.
Samira
S
Azizkhani
Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran; Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
Abbas
A
Farahani
Department of Microbiology, Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, IR Iran.
Baharak
B
Norozi
Coa gene; Methicillin-Resistant Staphylococcus aureus; Restriction Fragment Length Polymorphisms; Staphylococcus aureus; aroA gene