Abstract
BACKGROUND AND AIMS: Pseudomonas aeruginosa is a non-fermentative, opportunistic Gram-negative bacterium that causes 10%-15% of nosocomial and burn wound infections worldwide. This bacterium is resistant to various antibiotics through multiple mechanisms, including acquisition of resistance genes. The aim of this study was to perform a phenotypic and genotypic analysis of blaPER-1, blaVEB, and blaSHV-1 genes in clinical isolates of P. aeruginosa. METHODS: One hundred and ten P. aeruginosa isolates were collected from clinical specimens. The pattern of antimicrobial resistance was determined using the disk diffusion method. Phenotypic analysis of ESBL production was performed using the combined disk method. Additionally, molecular identification of blaPER-1, blaVEB, and blaSHV-1 β-lactamase genes was carried out by polymerase chain reaction (PCR). RESULTS: The highest resistance and sensitivity were observed against ceftazidime (86.36%) and colistin (78.18%), respectively. Among the 110 isolates, 72 were phenotypically ESBL-producing. The blaPER-1 gene was detected in 33 isolates (45.83%), blaVEB in 18 isolates (25.00%), and blaSHV-1 in 27 isolates (37.50%). CONCLUSION: Overall, phenotypic analysis indicated that 65.45% of isolates were ESBL producers, and the presence of blaPER-1, blaVEB, and blaSHV-1 genes was associated with increased resistance to ceftazidime, amikacin, ciprofloxacin, cefepime, and gentamicin. However, further studies are needed on ESBL-producing isolates, as well as the identification of effective antibiotics for the treatment of P. aeruginosa infections.