Negar Velayati - Burn & Wound Healing Research Center, Microbiology Department, Shiraz University of Medical Science, Shiraz
Amir Emami - Burn & Wound Healing Research Center, Microbiology Department, Shiraz University of Medical Science, Shiraz
Neda Pirbonyeh - Burn & Wound Healing Research Center, Microbiology Department, Shiraz University of Medical Science, Shiraz
Mahrokh Rajaee - Burn & Wound Healing Research Center, Microbiology Department, Shiraz University of Medical Science, Shiraz

Introduction: Pseudomonas aeruginosa is non-fermented and aerobic bacillus bacterium that is recognized as the third opportunistic hospital pathogen and the first cause of bacterial burn wound infections. This bacterium has several pathogenicity factors and, besides, it tends to form biofilms. P. aeruginosa has a genetic ability to produce at least 3 types of secretion polysaccharides, named as Alginate, PSL and Pel, which are require for production of biofilms. We aimed to focus on strains of p. aeruginosa that are collected from burn patients and they have talent to produce biofilms. Either in the following of study we check the presence of genes such as algK, algE, pslB and pelG that perform a function in biofilm formation and also evaluate the antibiotic sensitivity pattern by Disk diffusion method.Methods: In this descriptive and cross-sectional study, about 200 bacterial specimens were collected from the wound, urine and swab of the clinical samples of patients admitted to the Amir-al-momenin hospital of Shiraz. Firstly isolates were detected by phenotypic and API20E systems, then Antibiotic resistance test of the isolates were determined by disc diffusion method according to the CLSI protocol.Results: total of 88 samples were detected as P.aeruginosa. The rate of antibiotic resistance d in this study was Ciprofloxacin 50(56.8%) and Aztreonam 40(45.5%), Piperacillin 55(62.5%) and Carbenicillin 66(75%), Meropenem 44(50%), Imipenem 55(62.5%) and Ceftazidime 56(63.6%), Gentamycin 58(65.9%), Tobramycin 58(65.9%) and Colistinum 1(1/1%). Total of 78(88.6%) of the isolates was biofilm positive while 79.5%, 60.2% and 67% were harbor pelG, pslB and algE/K genes respectively.Conclusion: The results show a high prevalence of biofilm power production and an increase in the pseudomonades antibiotic resistance to the conventional antibiotics used in hospitals, due to orders for Antibiotic abuse in clinical states.