Examining the Frequency of bla CTX-M and bla TEM Genes in Escherichia Coli Isolates with Multiple Drug Resistance Isolated from Patients Hospitalized in Ahvaz University Hospitals

In the last few decades, Escherichia coli strains producing extended-spectrum beta-lactamases (ESBLs) have increased and are now considered a major problem in hospitalized patients. The aim of this study was to investigate the prevalence of blaCTX-M and blaTEM genes in Escherichia coli with multiple drug resistance.

This study was conducted from October 2021 to May 2022. The research site included the microbiology laboratories of Golestan, Imam Khomeini, and Shahid Beqai hospitals where isolates suspected of Escherichia coli were isolated from urine culture samples of patients with urinary tract infection. All Escherichia coli samples were identified by conventional biochemical and molecular methods. The antibiotic sensitivity of the isolates was determined by disk diffusion method. Then, in order to finally confirm the presence of blaCTX-M and blaTE genes, PCR method was used.

Out of the 160 bacterial isolates examined, 138 (86.3%) showed multidrug resistance (MDR). The highest and lowest percentage of resistance was related to Amoxicillin-Clavonic acid (84.1%) and Meropenem (5.8%), respectively. Based on the combined disk method, 96 isolates (69.6%) were positive for Beta-lactamase enzymes (ESBLs). Among the 96 ESBL-positive isolates, 85 (88.5%) and 38 (39.6%) carried blaCTX-M and blaTEM genes, respectively.

Conclusion:

 Given the significant prevalence of Escherichia coli strains that are resistant to multiple drugs and carrying ESBLs beta-lactamase genes in hospital, there is a need for effective surveillance measures to prevent the further spread of drug resistance in these isolates.