Detecting some virulence genes in Pseudomonas aeruginosa isolated from different clinical sources

Abstract

P. aeruginosa is an opportunistic pathogen capable of infecting almost all tissues of the body due to its possession of a wide variety of virulence factors that contribute significantly to pathogenicity in the host. In the current study, (102) samples are collected from different clinical sources, to detect the spread of P. aeruginosa bacteria in these sources and to study some virulence genes possessed by this bacteria. The developing isolates are diagnosed after cultivation on Blood agar and MacConkey agar according to phenotypic, microscopic and culture properties, and the diagnosis is confirmed using API 20E kit. The results of the diagnosis have shown that 33 isolates belong to the type P. aeruginosa from the total clinical samples, distributed by (11 isolates for burn injuries, 12 isolates for wounds and 10 isolate samples for urinary tract infections). The sensitivity of the bacterial isolates to 15 antibiotics is tested, and the results have shown that all isolates are resistant to Ceftriaxone, Colistin, and Amoxicillin by 100%, to Ceftazidime and Nalidixic by 96% and 90% respectively, to Gentamicin by 66%, to Tobramycin and Cefepime by 40%, to Piperacillin, Aztreonam, and Meropenem by 33.3%, to Ciprofloxacin, Levofloxacin and Imipenem by 23.3%, and to Norfloxacin by 16.6%. The prevalence of genes encoding the production of the basal protease enzyme aprA and elastase enzyme lasB, is detected using the (PCR) technique. The results reveal the presence of the aprA gene and the lasB gene with a rate of (100) within the genotype of the P. aeruginosa isolates under study. One of their high presence is most of the sources of the studied isolates, these genes can be considered a successful and rapid alternative for diagnosing P. aeruginosa by molecular methods based on the polymerase chain reaction (PCR) technique.