Molecular Epidemiology and Antimicrobial Resistance of ESBL- and Carbapenemase-Producing Uropathogenic E. coli and K. pneumoniae in Community-Acquired UTIs in Baghdad, Iraq

Urinary tract infections (UTIs) are common community-acquired infections caused by Escherichia coli and Klebsiella pneumoniae.This study examined the patterns of antimicrobial resistance and the genetic factors responsible for extended-spectrum βlactamase production in E. coli and K. pneumoniae isolates collected from UTI patients.This study analyzed 42 E. coli and K. pneumoniae isolates from female UTI patients in Baghdad.Phenotypic and genotypic methods assessed antibiotic resistance, plasmid types, clonal relationships, and horizontal gene transfer using polymerase chain reaction (PCR), multilocus sequence typing, Etest, disk diffusion, conjugation, electroporation, and sequencing techniques.The results revealed high resistance rates to multiple antibiotics, including ciprofloxacin (92.31%), gentamicin (76.92%), amoxicillinclavulanic acid (92.31%), ceftazidime (87.18%), and cefotaxime (76.92%).Imipenem showed the highest sensitivity (76.92%).Molecular analysis identified blaCTX-M-15 in K. pneumoniae ST15 and E. coli ST131 clones, while blaKPC-2 was detected in carbapenemresistant E. coli.Plasmid profiling revealed IncF-type plasmids as key vectors for resistance gene dissemination.The fingerprinting techniques confirmed clonal transmission, with identical isolates detected across hospitals, suggesting nosocomial spread.Notably, a patient persistently colonized with KPC-2-producing E. coli acted as a potential reservoir.The research findings underscore that the clonal spread of ST131 and KPC-2 carriage represents significant nosocomial threats, warranting urgent containment measures.