Prevalence of some metallo β-lactamase enzymes genes in P. aeruginosa isolated from different clinical sample in Baghdad, Iraq.

The increasing challenge of carbapenem antibiotics resistance caused by Pseudomonas aeruginosa is one of the global healthcare problems. P. aeruginosa is a significant opportunistic infection. For epidemiological reasons, identifying resistance genes is essential, and it is also desirable to quickly identify the techniques for producing carbapenemase enzymes. So, the study aims to determine the prevalence of beta-lactamase encoding genes (blaIMP, blaVIM, bla GIM, and bla SPM) phenotypically and genotypically in P. aeruginosa isolates to address the epidemiological spread of these genes in Baghdad city. The study identified P. aeruginosa isolates from various clinical sources by chemical characterization and VITEK 2 system, the antibiogram test, phenotypic screening carbapenem resistance by Combined disk synergy test (CDST), and conventional PCR were used to detect presence of VIM, IMP, SPM, and GIM genes. Bacterial susceptibility testing revealed (40 %) of isolates were resistant to Imipenem and (85 %) of them positive to CDST. Genotypic screening on phenotypic Metallo-β-lactamase isolates showed that (100 %) isolates contained blaVIM genes, blaGIM genes (88 %), whereas (65 %) isolates carried blaSPM genes. In this investigation, there was no evidence of blaIMP among carbapenem-resistant isolates. The study appeared high prevalence of multi-drug resistance P. aeruginosa isolates that produce carbapenemase enzymes and having β-lactamase genes in local hospitalized patients compared to global ratio. Expanding the sample size and types of enzymes screening in MDR P. aeruginosa should be the main focus in the future research.