Prevalence of blaCTX-M and blaTEM genes in Enterobacter cloacae isolated from urine samples in Iraqi patients

clinically relevant uropathogen and an increasing cause of opportunistic infections is Enterobacter cloacae, primarily driven by worldwide distribution of extended-spectrum β-lactamase--encoding genes. Among those, blaCTX-M and blaTEM are predominant genes responsible for the resistance towards β-lactam antibiotics and hence restricting treatment choices. The present work was designed to analyse the occurrence of blaCTX-M and blaTEM genes in E. cloacae isolated from urine samples of Iraqi patients, as well as assess their correlation with antimicrobial resistance profile. This condition-specific, cross-sectional study was performed at Al-Sadr Medical City Hospital, in Najaf in Iraq from summer season 2024 to early winter 2025. Eighty-four patients with a suspicion of UTI were included in this study. Midstream urine specimens were cultured and E. cloacae isolates were identified by routine microbiological and biochemical tests. Susceptibility to ceftriaxone, ciprofloxacin, gentamicin, imipenem and meropenem testing was determined by the Kirby–Bauer disc diffusion method according to CLSI guidelines. blaCTX-M and blaTEM genes were identified by traditional PCR. The relationship between gene carriage and antibiotic resistance was evaluated by statistical analysis. Ceftriaxone (75.0%) had the highest resistance rate, followed by ciprofloxacin (54.8%), and gentamicin (48.8%), while meropenem (16.7%) and imipenem (14.3%) were less resistive agents. Molecular investigation determined the prevalence of blaCTX-M and blaTEM genes in 69.0% and 52.4% of isolates, respectively. The presence of blaCTX-M and resistance ceftriaxone, ciprofloxacin and gentamicin (p < 0.001) were highly significantly associated between them while resistant to ceftriaxone and ciprofloxacin had a significant association with blaTEM (p < 0.05). The presence of either gene did not show a statistically significant relationship with carbapenem resistance. The high rates of blaCTX-M and blaTEM genes among urinary E. cloacae isolates drawn attention to the emerging problem of ESBL-mediated resistance in Iraq. The high prevalence of ESBL gene carriage and resistance to the commonly used antibiotics calls for ongoing molecular surveillance, judicious antibiotic use, and implementation of efficient infection control measures to curb the spread of resistant E. cloacae strains.