DISTRIBUTION OF ENTB AND KFU GENES AMONG KLEBSIELLA PNEUMONIAE ISOLATES RECOVERED FROM CLINICAL AND ENVIRONMENTAL SAMPLES IN NAJAF, IRAQ

Abstract

Objective: Klebsiella pneumoniae is a clinically significant opportunistic pathogen known for its multidrug resistance and virulence potential. Among its virulence determinants, the iron acquisition genes kfu and entB play critical roles in systemic dissemination and persistence. This study aimed to detect the presence of kfu and entB genes in clinical and environmental isolates of K. pneumoniae from Najaf, Iraq,  

Methods: A total of 29 bacterial isolates were collected from different sources such as urine, sputum, and wound specimens and 1 isolate was collected from environment. Identification of K. pneumoniae was performed using colony morphology, Gram staining, biochemical tests, and confirmed by the VITEK 2 compact system. String test has been carried out for detection Hyper virulent K. pneumoniae (hvKP). Molecular detection of kfu and entB was conducted using multiplex PCR with gene-specific primers.

Results: All isolates were identified as K. pneumoniae with low percentage (20.68%) of occurrence of hvKP (6 isolates only). Antimicrobial susceptibility testing revealed high resistance rates across multiple agents.    High antibiotic resistance reported to Amoxicillin-Clavulanic Acid (AMC) (100%), followed by Ceftazidime (CAZ) and Rifampicin (R5) (96.5%), while Imipenem showing the highest susceptibility.  The entB gene was detected in all isolates (100%), while kfu was present in only 4 isolates (13.8%). The universal presence of entB suggests its fundamental role in iron chelation and bacterial survival, while the limited distribution of kfu may indicate strain-specific virulence potential.  

Conclusion: These findings underscore the importance of iron acquisition systems in K. pneumoniae pathogenesis and highlight the need for targeted molecular surveillance and therapeutic strategies.