Background: Staphylococcus aureus, as one of the most common causes of nosocomial infections, has widely spread to all parts of the world and is becoming a serious concern in public health. Objectives: The present study aimed at evaluating the prevalence of adhesion and toxin gene profiles and their distribution among different agr types. Methods: The current cross-sectional study was performed in Tehran, Iran, by analyzing 125 methicillin resistant Staphylococcus aureus (MRSA) strains isolated from hospitalized patients at the ICUs from March, 2016 to January, 2017. In vitro antibiotic susceptibility testing of isolates was assessed using the Kirby-Bauer disk diffusion method. The MRSA strains were genetically typed by agr typing and virulence and adhesion genes profile by conventional PCR. Results: Antibiotic susceptibility testing showed that inducible macrolide-lincosamide-streptogramin B, constitutive macrolidelincosamide-streptogramin B, and high-level mupirocin resistance phenotypes had a frequency of 18 (14.4%), 50 (56%), and 10 (31.3%), respectively. The predominant resistance profile among MDR-MRSA isolates included resistance profile to seven antibiotics (32%). A total of ten virulence genotypes were observed, from which genotype spa, clfA, clfB, fnbB, fnbA, ebp, and can / tst (36%, 45/125) comprised the majority followed by spa, clfA, clfB, and fnbB (24%, 30/125). Type I was the most prevalent agr type (52%), followed by type III (34.4%), type II (9.6%), I 5(5.3%), and IV (4%). All isolates carrying PVL-encoding genes and HLMUPR-MRSA strains corresponded exclusively to agr type I. Conclusions:The current data demonstrated that virulence gene profiles among different agr types of MRSA isolates were divers. The present study suggests that molecular characterization of MRSA strains should periodically be studied.

Background: Urinary tract infection (UTI) is one of the most frequent types of infections in community and hospital settings. Objectives: The aim of the present study was to investigate antimicrobial susceptibility patterns and also to determine spa and SCCmec types of Staphylococcus aureus strains isolated from patients with UTI. Methods: During a 12-month period, 863 urine samples were investigated. In vitro susceptibility of isolates was performed using the Kirby-Bauer disk diffusion method. Moreover, conventional PCR was performed to detect mecA, nucA, spa, and toxin (pvl, tst) genes as well as Multiplex PCR to determine SCCmec types. Results: A total of 90 isolates (10.4%) were analyzed in the present survey. Methicillin resistance was observed in 61.1% of the isolates. In total, 25 isolates (27.8%) were positive for the pvl-encoding gene and 40 (44.4%) for tst-1 encoding gene. Based on a multiplex PCR assay, the 4 different SCCmec types were detected as type III (38.9%), followed by type II (31.1%), type IV (28.9%), and type I (1.1%). PantonValentine Leukocidin (PVL) positive isolates belonged to SCCmec type IV (14.4%) and II (13.3%). The 90 S. aureus isolates were classified to 10 spa types t037 (23.3%), t924 (15.6%), t383 (15.6%), t426 (12.2%), t044 (12.2%), t790 (6.7%), t084 (4.4%), t021 (4.4%), t7580 (4.4%), and t064 (1.2%). The spa types t044, t790, and t084 were obtained from methicillin-resistant S. aureus (MRSA) strains and spa types t924 and t7580 from methicillin-sensitive S. aureus strains. Conclusions: To the best of the author's knowledge, this is the first study on spa types t426 and t021 in Iran. Since the majority of strains isolated from patients with UTI were MRSA, detection of MRSA clones and their characteristics is necessary.