Molecular Typing and Virulence Analysis of Pseudomonas Aerugınosa Isolated From Burn Infections Recovered From Duhok and Erbil Hospitals/Iraq

In this study, 225 isolates of Pseudomonas aeruginosa were recovered from burn wounds in major hospitals in Duhok and Erbil, Iraq, between April 2015 and September 2015. A total of 136 of these isolates were from men, comprising 60.4% of the total, whereas 89 (39.6%) were recovered from women. One hundred of these isolates were selected (50 from each province of Erbil and Duhok) and subjected to 16 different antibiotics using the disc diffusion method. The isolates showed a high level of resistance to most of the tested antibiotics, with 90% of the isolates being multidrug resistant. Imipenem was considered as the most effective antibiotic against these isolates with a resistant rate of 47%. The genome of all of these isolates were successfully amplified and produced a single band for the 16S rDNA locus with a molecular weight of about 956 base pairs, which was used to confirm, at the molecular level, that all these isolates were indeed P. aeruginosa. The results of the detection of five virulence-related genes including opr1, toxA, exoS, lasB, and nan1 revealed that 10 of these isolates, accounting for 10%, lacked any of the tested virulence markers. The opr1 gene, as a marker for the presence of a pathogenicity island, was the most dominant marker among all the virulence markers and was detected in 90 isolates (90%), followed by the toxA and exoS genes, which were both observed in 86 (86%) isolates, whereas the lasB gene was found in 82 (82%) isolates and the nan1 gene in 35 (35%) of the isolates, respectively.