Paper Title
Prevalence Of Biofilm Producing Genes (Icad, Icaa) In Clinical Samples Of Staphylococcus Aureus Isolated From Rasht City

Abstract
Background and purpose: Staphylococcus aureus biofilm associated infections remains a major clinical concern in patients with indwelling devices. Staphylococcus aureus is recognized as the most important pathogen responsible for nosocomial infections and it is one of the public - health threats due to resistance to methicillin and anti - microbial drugs. The aim of present study was to find the incidence of Methicillin resistant Staphylococcus aureus (MRSA) strains isolated from clinical samples in Rasht city. The purpose of this study was the antibiotic resistance pattern, amplification of mecA gene, investigation the biofilm formation ability and presence of icaA and icaD genes. Material and methods: A total of 250 clinical samples were collected from hospitals in Rasht city. At first, Staphylococcus aureus isolates were recognized by microbiological tests and ability of biofilm formation and Presence of mecA, icaA and icaD genes were analyzed by PCR. Results: Totally, 50 Staphylococcus aureus isolates were characterized. Based on phenotypic biofilm test, 30(60%) of the 50 isolates were positive, but the prevalence of icaA and icaD genes in isolates was 78%. In addition, the mecA gene was observed in 30 (60%) of 50 S. aureus isolates. Conclusion: The results showed that the prevalence of MRSA was remarkable in the hospital samples and biofilm formation ability was observed in some clinical isolates of Staphylococcus aureus. Moreover, bacterial biofilms show increased tolerance to antibiotics. This is a serious problem in medical centers specially, in intensive care units. Keywords� Biofilm, Methicillin resistant Staphylococcus aureus (MRSA), mecA