Urinary tract infections caused by carbapenem-resistant Gram-negative bacteria among pregnant women attending antenatal care clinic at Murang’a County Referral Hospital, Kenya

Urinary tract infections (UTIs) continue to pose a significant health risk during pregnancy, with growing antimicrobial resistance making effective management increasingly challenging. Of more significance is the emergence of carbapenem-resistant (CR) bacteria, especially in resource-limited countries where diagnostic capabilities, treatment options, and comprehensive epidemiological data are inadequate. This study aimed to describe the prevalence, antimicrobial co-resistance patterns, and factors associated with UTIs caused by CR Gram-negative bacteria (GNB) among pregnant women at Murang'a County Referral Hospital in Kenya. A hospital-based cross-sectional study involving 365 pregnant women was conducted from May to October 2023. Participants were recruited through systematic random sampling; each underwent clinical evaluation. Demographic information was collected using a structured questionnaire, while clinical data were obtained from hospital records. Clean-catch midstream urine samples were processed in the hospital's microbiology laboratory using standard microbiological techniques. The overall prevalence of UTIs was 25.5% (93/365; 95% CI: 21.01-29.95), with GNB (76.3%, 71/93) predominating. The prevalence of UTIs caused by CR-GNB and carbapenemase-producing (CP)-GNB was 4.93% (95% CI: 2.71-7.15) and 2.7% (95% CI: 1.07-4.41), respectively. Escherichia coli (E. coli) was the predominant pathogen overall (60.3%), and among CR-GNB (72.2%) and CP-GNB (60%) UTIs. More than half (10/18, 55.6%) of CR isolates co-produced extended β-lactamases (ESBLs) and carbapenemases. No colistin resistance was detected in carbapenem-resistant isolates. Co-resistance ranged from 38.5% to 92.3%, with the lowest resistance (≤ 46.2) to nitrofurantoin and aztreonam. High co-resistance (≥ 69%) was observed for most β-lactams, cephalosporins, aminoglycosides, and trimethoprim/sulfamethoxazole. 89% of CR isolates, including all CP-GNB, were multidrug-resistant. Multiple antibiotic resistance indices (0.67-0.93) were highest among CP isolates. Unmarried/single women were more likely to have UTIs caused by CP-GNB (adjusted odds ratio: 8.87; 95% CI: 1.57-50.01). Carbapenemase- and ESBL-co-producing GNB, predominated by E. coli, were present among pregnant women with UTIs. Unmarried/single status was the only variable significantly associated with CP-GNB UTIs in this study. Strengthening carbapenem stewardship and enhancing infection prevention practices are urgently needed to prevent further spread of resistant strains in the current context and beyond.