TITLE:
Carbapenem Resistance and Metallo-β-Lactamase Production in Enterobacteriaceae Isolated from Urogenital Tract Infections in Brazzaville
AUTHORS:
Nicole Prisca Makaya Dangui Nieko, Tarcisse Baloki Ngoulou, Doria Moïse Kaya-Ongoto, Faly Armel Soloka Mabika, Vikène Juste Babela Koumou, Etienne Nguimbi
KEYWORDS:
Resistance, Metallo-Betalactamases, Enterobacteriaceae, Brazzaville
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.16 No.11,
November
25,
2025
ABSTRACT: The emergence and spread of antibiotic-resistant bacteria constitute a major global public health threat, compromising treatment efficacy and increasing morbidity and mortality associated with infections. In response to this concerning situation, carbapenems are considered last-resort antibiotics. However, Enterobacteriaceae exhibit high resistance rates to these drugs. The aim of this study was to determine carbapenem resistance profiles and the prevalence of Metallo-β-Lactamase (MBL) production among Enterobacteriaceae isolated from urogenital tract infections. Enterobacteriaceae strains were isolated on selective media from urine and vaginal swab samples and identified using the API 20 E system. Antibiotic susceptibility testing was performed using the Mueller-Hinton disk diffusion method. MBL production was assessed using the combined carbapenem/carbapenem + EDTA disk test. A total of 123 Enterobacteriaceae were isolated from 325 samples, of which 81.6% were from urine and 17.4% from vaginal swabs. Identification revealed 12 species distributed across five genera: Escherichia, Enterobacter, Citrobacter, Klebsiella, and Proteus. Susceptibility testing showed the highest sensitivity to ertapenem (79.67%) followed by meropenem (69.92%), whereas doripenem showed the lowest sensitivity (33.33%). Resistance patterns varied between species for different antibiotics. Chi-square analysis revealed a significant difference in bacterial resistance among the different strains for all tested antibiotics. MBL production testing revealed that 100% of strains produced MBLs in the presence of imipenem. Only E. coli and Enterobacter aerogenes were MBL producers in the presence of meropenem. Despite the high resistance rates and the capacity of these strains to produce carbapenem-hydrolyzing enzymes, meropenem and ertapenem, due to their lower resistance rates, may still be considered first-line treatment options for urogenital tract infections caused by these bacterial genera.