Aghdas Bibi Hashemi - Department of Biology, Faculty of Science, Mashhad Branch, Islamic Azad University, Mashhad, Iran
Mahboobeh Nakhaei Moghaddam - Department of Biology, Faculty of Science, Mashhad Branch, Islamic Azad University, Mashhad, Iran
Mohammad Mahdi Forghanifard - Department of Biology, Faculty of Science, Damghan Branch, Islamic Azad University, Damghan, Iran
Ehsan Yousefi - Department of Biology, Faculty of Science, Mashhad Branch, Islamic Azad University, Mashhad, Iran

Introduction: The rapidly increasing extended-spectrum β-lactamase-producing Pseudomonas aeruginosa is a threat to health. This study aims to detect the rpoD gene and blaOXA-۱۰ and blaOXA-۴۸ genes in imipenem-resistant P. aeruginosa clinical isolates simultaneously by multiplex polymerase chain reaction. Methods: Eighty-five culture plates were collected from patients suspected of Pseudomonas spp infection in Ghaem Hospital and Shahid Shourideh Clinic in Mashhad from January to February ۲۰۲۱. After biochemical identification of P. aeruginosa isolates and the measurement of antibiotic resistance, blaOXA-۱۰, blaOXA-۴۸, and rpoD genes were investigated by multiplex polymerase chain reaction in the imipenem-resistant isolates. Results: Of ۸۲ P. aeruginosa isolates, ۳۸ (۴۶.۳۴%) were resistant to imipenem, with the highest percentage to carbenicillin (۶۹.۵%). All imipenem-resistant P. aeruginosa isolates were confirmed by multiplex PCR using the primers that targeted the rpoD gene. Also, in multiplex PCR, among imipenem-resistant isolates, ۱۰ (۲۶.۳%) and ۹ (۲۳.۶%) had blaOXA-۱۰ and blaOXA-۴۸ genes, respectively. Conclusion: In addition to molecular identification of P. aeruginosa, the present study simultaneously detected blaOXA-۱۰ and blaOXA-۴۸ genes by multiplex PCR. Application of this multiplex PCR, rapid identification of patients, and timely treatment can reduce the β-lactamase gene prevalence in P. aeruginosa clinical isolates.

Pseudomonas aeruginosa, Multiplex PCR, rpoD gene, blaOXA-۱۰ gene, blaOXA-۴۸ gene