ESBL, AmpC β-Lactamases, and NDM Genes' Co-Existence and its Association with Multidrug Resistance among E. coli Isolated from UTI

Abstract

 The occurrence of multidrug-resistant Escherichia coli in urinary tract infections is considered the emergent health concern among world countries, particularly in the regions with limited clear antimicrobial resistance surveillance. The aime is assessed the β-lactamase-production profile of the E. coli and evaluate the complicated resistance pattern as gene co-occurrence outcomes among UTI patients. This study includes 212 urine samples collected from males and females, where 168 samples exhibited microbial growth, where the E. coli demonstrated a predominance (68%) among the isolated pathogens. However, the antimicrobial susceptibility reveals an elevated resistance rate toward most tested antibiotics, including amoxicillin/clavulanic acid (80%) and third-generation cephalosporins (≥61%). While nitrofurantoin (13%), carbapenem (≤12%), and aminoglycoside resistance (≤8%) remained the most susceptible ones. Additionally, the phenotypic confirmation demonstrated 67% of isolates were ESBL producers and AmpC producers. The genotypic investigation exposed a high frequency of ESBL genes: CTX-M-1 (86%), TEM-1 (85%), and OXA-1 (75%), with frequent co-occurrence between them. SHV-1 was the least distinguished gene (30%). The pAmpC is predominantly revealed (97%) among the isolates, in contrast to the CMY gene and the NDM gene, which were noticed in 19% and 9% of the isolates, respectively. However, a strong correlation has been found between the existence of ESBL genes and the resistance pattern of tested beta-lactam antibiotics (p< 0.001). In conclusion, the high occurrence of ESBL, AmpC, and NDM genes contributes to increasing the intensity and complexity of resistance patterns, therefore accelerating the occurrence of MDR among E. coli isolates.