Investigation Genetic of Enterobacteriaceae isolated from sewage of Baghdad Hospital

This study aimed to investigate the presence of the blaTEM and blaSHV genes in 50 environmental isolates obtained from the Tigris River. The isolates were biochemically identified using the VITEK-2 system, which enabled precise species-level identification. The results of biochemical analyses revealed that the predominant species among the isolates were Klebsiella pneumoniae (44.44%), Proteus mirabilis (31.48%), Enterobacter aerogenes (12.96%), Citrobacter freundii (7.40%), Citrobacter koseri (1.85%), and Enterobacter spp. (1.85%). Antimicrobial susceptibility testing against 20 antibiotics indicated a high level of resistance, with 100% of isolates exhibiting resistance to penicillin’s and aminopenicillins (ampicillin and amoxicillin). Furthermore, resistance to tetracycline (81.18%) and gentamicin (63.16%) was observed. Molecular detection of resistance genes via PCR revealed that blaTEM was present in 48.14% of the isolates, while blaSHV was detected in 33.3%. The presence of these genes highlights the potential dissemination of extended-spectrum β-lactamases (ESBLs) in environmental sources, particularly in hospital-associated sewage.