Genotyping and Molecular Characterization of Carbapenem-resistant Acinetobacter baumannii Strains Isolated from Intensive Care Unit Patients

Abstract

The emergence of multidrug-resistant Acinetobacter baumannii has partly increased treatment failure and patient mortality. Class D β-lactamases is an important mechanism of resistance to beta-lactam antibiotics in this species. This study aimed to investigate the relationship between the presence oxacillinase gene and genetic fingerprints of A. baumannii isolates from the intensive care unit of an Egyptian tertiary care hospital. One hundred and twenty A. baumannii clinical isolates were collected. Multiplex PCR was performed to detect genes encoding oxacillinases (OXA-23, OXA-24, OXA-51, OXA-58 and OXA-143). Molecular typing of all collected isolates was performed using random amplified polymorphic DNA (RAPD)-PCR assay. Out of 120 examined isolates, 92, 88 and 84% were resistant to ertapenem, imipenem and meropenem, respectively. The species-specific, commonly present OXA-51 gene was found in all isolates while OXA-23 showed a high prevalence of 88% of isolates. OXA-24 and OXA-143 genes were detected in 3% and 1% of isolates, respectively. No OXA-58 gene was detected. Five clusters consisting of 19 genotypes were detected using RAPD-PCR. Genotype A was the most prevalent, it was observed in 62% of the isolates followed by genotype B (12%). These results revealed that genotypes A and B are common in the hospital. Results also demonstrate that RAPD-PCR is a rapid and reliable method for studying the clonal similarity among A. baumannii isolated from different clinical specimens.

Genotyping of carbapenem resistant Acinetobacter baumannii isolated from Egyptian patients

“…There are many reports indicating the presence of bla OXA-58 in A. baumannii clinical isolates throughout different parts of the world, where different rates of bla OXA-58 were previously detected in Tunisia, Egypt, and Algeria, recording 4 %, 9.1 %, and 14.7 %, respectively (Abouelfetouh et al, 2019). However, bla OXA-58 was absent in all A. baumannii isolates collected in this study, in agreement with the previous studies conducted in Mansoura, Egypt, by Benmahmod et al, (2019); Abozahra et al, (2021). However, other Egyptian studies of Al-Hassan et al, (2019);Hassan et al, (2021);Wasfi et al, (2021) reported different percentages of existence of this gene, recording 3.3 %, 1.9 %, and 2.9 %, respectively.…”

“…The present study showed a moderate level of carbapenem resistance (65 %), in comparison with several Egyptian studies, including Al-Hassan et al, (2019);Benmahmod et al, (2019); Abozahra et al, (2021); Eshra, (2021); Ibrahim et al, (2022), which reported resistance rates of 95.7 %, 93 %, 98 %, 91.6 %, 88.9 %, and 100 %, respectively.…”

Molecular epidemiology of carbapenem-resistant Acinetobacter baumannii isolates in Turkiye: Systematic review

“…MDR, WDR, and PDR observed in A. baumannii strains also express carbapenem resistance and occur through mechanisms including decreased permeability with changes in porin-like proteins, decreased intracellular antibiotic concentrations as a result of the activity of efflux pumps, and the production of enzymes such as β-lactamases [ 5 ].…”