Phenotypic and genotypic characterization of carbapenemase-producing Escherichia coli clinical isolates in Thi-Qar, Iraq

Moslim Mohsin  Khalaf; Firas Srhan Abd  Al-Mayahi

doi:10.18502/ijm.v17i2.18387

Moslim Mohsin Khalaf Department of Pathological Analysis, College of Applied Medical Sciences, Al-Shatrah University, Thi-Qar, Iraq
Firas Srhan Abd Al-Mayahi Department of Biology, College of Science, University of Al-Qadisiya, Al-Qadisiya, Iraq

DOI: https://doi.org/10.18502/ijm.v17i2.18387

Keywords: Antibiotic resistance; Beta-lactam resistance; Carbapenems; Doripenem; Escherichia coli; Imipenem; Mero- penem

Abstract

Background and Objectives: The emergence of carbapenem resistance in Escherichia coli (E. coli) poses an urgent threat. The study aims to assess carbapenem resistance and the presence of carbapenemase genes in E. coli clinical isolates from Thi-Qar Hospital, Iraq.

Materials and Methods: A total of 2203 specimens were collected from patients at two hospitals between January and October 2024. E. coli was identified via biochemical tests and confirmed with the Vitek2® system. Antibiotic sensitivity was evaluated using disc diffusion, and carbapenemase production was investigated through combined disc tests (CDT) and modified Hodge tests (MHT). PCR was used to detect carbapenemase genes.

Results: Out of 2203 specimens, 1212 (55.02%) exhibited bacterial growth, with E. coli accounting for 15.35% (186/1212) of isolates. Among these, 40 (21.51%) were resistant to at least one carbapenem. CDT identified 10, and MHT identi- fied 1 as a carbapenemase producer. The most detected gene was bla NDM (60.00%), followed by bla OXA (40.00%) and bla OXA-48 (15.00%). bla OXA-51 and bla VIM were found in 5.00% of isolates each. No bla KPC , bla , bla , bla , bla SPM bla , or bla SIM was detected.

Conclusion: The high prevalence of carbapenem resistance and the corresponding encoding genes in E. coli in Thi-Qar province pose a concerning challenge for managing serious infections caused by this pathogen.