Prevalence of Carbapenemase Production Among Klebsiella and Escherichia coli Isolated From Urinary Tract Infections

Cureus. 2024 Oct 6;16(10):e70918. doi: 10.7759/cureus.70918. eCollection 2024 Oct.

Abstract

Background and aim Urinary tract infections represent a substantial portion of healthcare-associated infections due to E. coli and Klebsiella. Carbapenems are broad-spectrum antibiotics considered highly effective in treating infections caused by multidrug-resistant bacteria. Carbapenem-resistant Enterobacteriaceae (CRE), including carbapenem-producing E. coli and Klebsiella isolates, have become a major concern as they limit treatment options. The study aims to determine the prevalence of carbapenemase-producing E. coli and Klebsiella while also comparing the effectiveness of two detection methods, namely the modified carbapenem inactivation method (mCIM) and modified Hodge test (MHT). Materials and methods A cross-sectional study was conducted from July 2022 to June 2023 in a tertiary care hospital, in Karad, Satara, India. Three hundred urinary isolates of E. coli (150) and Klebsiella (150) were studied. These isolates were tested for antimicrobial susceptibility testing. Two phenotypic methods, the modified carbapenem inactivation method (mCIM) and the modified Hodge test (MHT), were used to study carbapenemase production. Results Out of three hundred isolates, carbapenemase production was detected in 72 isolates (24%) by the modified Hodge test (MHT) and in 111 isolates (37%) by the modified carbapenem inactivation method (mCIM). Among the MHT-positive isolates, 46 (63.8%) were identified as Klebsiella and 26 (36.1%) as E. coli. In contrast, of the mCIM-positive isolates, 68 (61.2%) were Klebsiella, and 43 (38.7%) were E. coli. A total of 41 Klebsiella (27.33%) and 25 E. coli (16.66%) isolates tested positive by both methods, highlighting variability in detection rates between the two methods. Conclusion This study observed MHT and mCIM to be accurate for the detection of carbapenemase among carbapenem-resistant isolates. However, the mCIM demonstrated greater sensitivity compared to the MHT.

Keywords: antimicrobial susceptibility; carbapenem-resistant enterobacteriaceae (cre); carbapenemase; e.coli; healthcare-associated infections; klebsiella; mcim; mht; phenotypic methods; urinary tract infection.