An Evaluation of Extended-Spectrum and CMY-2-Type Ampc Β-Lactamase-Producing Uropathogenic <i>Escherichia coli</i> Isolates in a Tertiary Care Hospital in Babylon Province, Iraq

Background: Urinary tract infections (UTIs) have become a serious epidemiological threat due to the emergence of β-lactamase-producing Escherichia coli isolates, which complicate the treatment and control of severe infections. Objectives: This study aimed to investigate the prevalence of extended-spectrum β-lactamases (ESBLs) and CMY-2-type plasmid-mediated AmpC β-lactamase (pAmpC) AmpC β-lactamase-producing uropathogenic Escherichia coli (pUPEC) isolates, and to identify the predominant phylogenetic group among these isolates. Methods: In this cross-sectional study, 150 uropathogenic Escherichia coli (UPEC) isolates with reduced susceptibility to third-generation cephalosporins (3GCs) and cephamycin were collected from a tertiary care hospital in Babylon province, Iraq, between November 2022 and March 2023. One hundred isolates exhibiting ESBL and/or AmpC phenotypes were selected for molecular analysis. Results: Genotypic characterization of ESBL and CMY-2-type AmpC β-lactamase-encoding genes revealed that 92% of the isolates carried β-lactamase genes. Among them, CTX-M was the most common genotype (76%), with CTX-M-15 being the most prevalent variant, followed by TEM (75%), SHV (73%), and CMY-2 (60%). Phylogenetic analysis showed that the extraintestinal group B2 (91.3%) was the most prevalent among the isolates, followed by group D (6.5%), which is also associated with extraintestinal infections. Conclusions: The high prevalence of ESBL/CMY-2-type pUPEC isolates associated with virulent extraintestinal infections underscores the urgent need for ongoing surveillance and the implementation of appropriate guidelines in public healthcare settings. To our knowledge, this study is the first to report the presence of CMY-2-type AmpC β-lactamase-producing pUPEC isolates in Iraq.