Carbapenemase Genes in Gram-Negative Bacteria: Detection and Implications in Clinical Isolates from Patient Samples

Egwuatu, Tenny O. G.; Ogunrinde, Oluwaseyi G.; Osibeluwo, Bisola V.; Osuagwu, Chioma S.

doi:10.21608/eajbsg.2023.310649

Carbapenemase Genes in Gram-Negative Bacteria: Detection and Implications in Clinical Isolates from Patient Samples

Document Type : Original Article

Authors

¹ Department of Microbiology, Faculty of Science, University of Lagos, Akoka, Nigeria

² Department of Medical Microbiology and Parasitology, Lagos University Teaching Hospital, Idi-Araba, Lagos, Nigeria.

10.21608/eajbsg.2023.310649

Abstract

Background: Antimicrobial resistance is a great scourge on human health, exacerbated by the acquisition of resistance to carbapenems, the last resort treatment for infections caused by extended-spectrum beta-lactamase (ESBL) producing bacteria. Objectives: This cross-sectional study evaluated the prevalence of genes encoding ESBL and carbapenemase production in Gram-negative bacteria from clinical samples in Lagos state, Nigeria.Method: A total of 107 bacteria cultures were obtained from hospitals and clinical diagnostic laboratories. Isolate identification, antibiotics susceptibility testing, and phenotypic detection of ESBL production were done using standardized procedures. Multiplex polymerase chain reaction (PCR) was performed on ESBL-producing isolates to detect bla_TEM, bla_SHV, bla_CTX-M, bla_KPC, bla_VIM, bla_IMP and bla_OXA.Result: Among the 107 cultures, 83 isolates were obtained with 55 being Gram-negative. Escherichia coli (22; 40%) was the most prevalent species followed by Klebsiella pneumoniae (7; 13%). Multidrug resistance (MDR) was observed in 34 (62%) of the isolated bacteria with 14 (26%) not susceptible to meropenem. ESBL production was detected in 42 (76%) of the isolates of which 23 (55%) strains harboured one or more of the genes bla_TEM, bla_SHV, and bla_CTX-M. The carbapenemase genes bla_KPC and/or bla_VIM were observed in 11 (26%) isolates. No isolated bacteria were found to harbour bla_IMP and/or bla_OXA.Conclusion: Genes encoding ESBL and carbapenemase production were detected in samples of human origin in Lagos state. Novel antibiotics and/or alternative therapy are necessary for infection therapy in the near future.