Detection of bla(PER-1) & bla(Oxa10) among imipenem resistant isolates of Pseudomonas aeruginosa isolated from burn patients hospitalized in Shiraz Burn Hospital

BACKGROUND AND OBJECTIVES: Pseudomonas aeruginosa is one of the most important Gram negative opportunistic bacteria which causes infection among burn patients. Resistance to the antibiotics in this group of bacteria is increased due to the activity of extended spectrum β-lactamase (ESBLs) genes. In the current study, we investigated the prevalence of two genes (bla(PER-1) & bla(Oxa10)) related β-lactamase genes among imipenem resistance clinical isolates of P. aeruginosa in hospitalized patients. MATERIALS AND METHODS: From May 2010 to March 2011, 270 P. aeruginosa isolated from hospitalized burned patients’ wounds in Shiraz Burn Hospital, were tested for Imipenem resistance by disk diffusion method. Presence of ESBLs exo-enzyme, bla(PER-1) and bla(Oxa10) genes were also evaluated in the resistant isolate. RESULTS: 210 (77.7%) of 270 P. aeruginosa isolates were resistant to imipenem. bla(PER-1) and bla(Oxa10) were detected among 168 (80.0%) of imipenem resistant isolates. Furthermore, 160 (76.2%) of them had bla(Oxa10) gene and 84 (40.0%) of them had bla(PER-1) while 63 (30.0%) resistant isolates contained both genes simultaneously. CONCLUSION: This study showed a high prevalence of bla(PER-1) and bla(Oxa10) genes in hospitalized burn patients in south west of Iran. Therefore, it’s highly recommended to perform such tests routinely to evaluate the resistance pattern in order to better antibiotic selection in the burned patients.