Prevalence of Class I Integron Gene in Carbapenem-Resistant Enterobacteriaceae Strains Isolated from Hospitalized Patients

Background: The prevalence of carbapenem-resistant Enterobacteriaceae (CRE) is a growing global public health concern due to the significant morbidity and mortality associated with infections caused by these bacteria. The main objective of this study was to determine the prevalence of class I integron in CRE isolates collected from patients in teaching hospitals affiliated to Mazandaran University of Medical Sciences (MAZUMS). Materials & Methods: A total of 100 Enterobacteriaceae isolates were collected during March 2022 to March 2023 from MAZUMS teaching hospitals using a consecutive sampling technique. The isolates were distinguished using standard microbiological methods. The antibiotic resistance of the isolated strains to carbapenem was subsequently detected using antibiotic discs including imipenem and meropenem. Using the disc diffusion method, 73 carbapenem-resistant isolates were identified and subsequently investigated by genetic analysis using polymerase chain reaction (PCR). Findings: Among the 73 carbapenem-resistant isolates, the most commonly found bacterial isolates were Klebsiella pneumoniae (39.72%), Escherichia coli (30.13%), and Serratia rubidaea (12.32%), respectively. Also, 100% of the isolates were resistant to meropenem, while these isolates showed lower resistance to imipenem (70%). Also, out of the 73 isolates, 64.38% were positive for the intI1 gene. K. pneumoniae isolates had the highest prevalence of the intI1 gene (89.65%). Conclusion: The prevalence of class I integron among patients in MAZUMS educational hospitals is relatively high, exceeding 50%. Therefore, it is crucial to implement effective infection prevention measures and identify this gene in hospitals to hinder the rapid dissemination of these hazardous organisms.