Background: Methicillin-resistant Staphylococcus aureus (MRSA) has become more prevalent all over the world and it is important to determine MRSA prevalence and typing in different regions. The present study was carried out to determine the prevalence and frequency of circulating molecular types of MRSA isolates as well as their antibiotics susceptibility in Tabriz and Kerman cities of Iran.
Materials and methods: A total of 230 S. aureus isolates were collected from Tabriz (n=125) and Kerman (n=105) during January to December 2018. MRSA isolates were identified by PCR amplification of nuc and mec A genes. Antibiotic susceptibility of MRSA isolates were determined by Kirby-Bauer disk diffusion method. Multiplex PCR was exploited to detect various types of SCCmec.
Results: The MRSA prevalence was 51/125 (40.8%) in Tabriz and 60/105 (57.1%) in Kerman. Overall, 36/51 (70.58%) and 15/51 (29.41%) isolates and 37/60 (61.66%) and 23/60 (38.34%) isolates were isolated from inpatients and outpatients in Tabriz and Kerman, respectively. Almost all of the isolates were resistant to penicillin and all of them were sensitive to linezolid. Thirty five (68.2%) and 34(56.6%) of MRSA isolates in Tabriz and Kerman were determined as MDR, respectively. SCCmec typing showed that the frequent SCCmec type in both Tabriz and Kerman cities was SCCmec III (56.86% and 55%, respectively).
Conclusion: The high prevalence of MRSA makes it necessary to revisit the antibiotics administration by physicians. Indeed, periodic evaluation of antibacterial susceptibility patterns of the MRSA strains is required for efficient treatment of MRSA infections.
Keywords: Methicillin-resistant bacteria; Staphylococcus aureus; staphylococcal cassette chromosome mec typing.