Background: To characterize and compare the epidemiological and microbiological aspects of community and healthcare-associated MRSA (CA-MRSA, and HA-MRSA) cases in Iran, this prospective cohort study was conducted from January to December 2008 in seven hospitals.Patients and methods: Staphylococci were isolated from 109 hospitalized patients. MRSA isolates were classified into HA-MRSA and CA-MRSA based on clinical features.Antibacterial susceptibility patterns of the isolates to eight antibiotics routinely used to treat infected patients were determined according to standard agar dilution methods.Staphylococcal Cassette Chromosome mec (SCCmec) type of isolates and their correlation with antimicrobial susceptibility patterns in CA and HC isolates were determined.Results: Of 109 isolates, 15 (13.7%) were community-associated and 94 (86.3%) were healthcare-associated MRSA.The most frequent SCCmec types in the studied hospitals were SCC mec type I (56.9%) and type II (22%). Relatively high resistance (>60%) of the MRSA to the seven tested antibiotics including: ciprofloxacin, trimethoprimsulfamethoxazole, clindamycin, rifampin, erythromycin, tetracycline and doxycycline were noticed.Conclusion: To our knowledge, this is the first time that the analysis of SCCmec type is carried out in Iran according to the clinical criteria. Difference in the prevalence of HC-MRSA and CA-MRSA based on the clinical and epidemiological features may indicate the need for revisiting the classification of MRSA. The high prevalence of multidrug resistant MRSA could be as a result of the excessive use of antibiotics in the hospitals. Therefore, periodical assessment of antibacterial susceptibility patterns of the MRSA strains is warranted.

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) represents a significant public health concern among long-term hospitalized patients, particularly those with weakened immune systems, such as cancer patients. This is primarily due to MRSA's ability to resist antimicrobial agents and drugs. The objective of this study is to ascertain the antibiotic resistance pattern of MRSA in cancer patients admitted to hospitals in the southwest region of Iran. The samples obtained from the patients were cultivated on blood agar and EMB medium. Subsequently, the positive samples containing S. aureus were identified through the application of a phenotypic method. Subsequently, the cefoxitin antibiogram was employed for the isolation of MRSA. Furthermore, the isolates were subjected to testing for simultaneous drug resistance against 12 different antibiotics. To detect the presence of the mec gene, a molecular method was employed, namely the polymerase chain reaction (PCR) technique, and electrophoresis of the obtained products was conducted. Of the 41 S. aureus samples identified, 33 were found to be methicillinresistant S. aureus (MRSA). Of the 33 MRSA isolates, the presence of the mec gene was confirmed, and they exhibited simultaneous drug resistance. Individuals with cancer, who frequently have indwelling catheters and receive a variety of drugs and blood products, are at an elevated risk of contamination with this bacterium due to its presence on their skin and the hands of healthcare providers. The indiscriminate use of drugs and the subsequent rise in drug resistance can contribute to prolonged hospitalization and even death among these individuals. Given that Ahvaz hospitals, particularly Bagai Hospital, serve as primary treatment centers for patients with incurable and cancerous conditions in southwestern Iran, it is of significant value and importance to investigate the resistance patterns observed in patients undergoing chemotherapy and post-transplantation.