Low Prevalence of Carbapenemase Gene NDM-1 in Uropathogenic Klebsiella pneumoniae and Escherichia coli: A Molecular Surveillance Study

Introduction: The New Delhi Metallo β lactamase 1 (NDM 1) gene has emerged as a major global health concern because of its ability to confer resistance to β lactam antibiotics, particularly carbapenems. These antibiotics are often considered last line agents, and resistance severely limits treatment options. NDM 1 is frequently associated with urinary tract infections (UTIs) caused by multidrug resistant Gram-negative bacteria, and its spread poses a serious challenge to patient care. Continuous surveillance is therefore essential to track its prevalence and guide effective treatment and prevention strategies.

Aim: This study set out to determine the prevalence of the NDM 1 gene in clinical isolates obtained from patients with UTIs in Onitsha Metropolis.

Methods: Thirty clinical isolates from patients diagnosed with UTIs were analyzed. Genomic DNA was extracted from each isolate, and the presence of the NDM 1 gene was assessed using Polymerase Chain Reaction (PCR). Amplified products were separated on agarose gel electrophoresis and visualized with ethidium bromide staining to confirm gene detection.

Results: Of the thirty isolates examined, only one tested positive for the NDM 1 gene. This finding corresponds to a prevalence rate of 3.33 percent among the studied samples. Although the prevalence was low, the detection of NDM 1 in even a single isolate is significant, given the potential for plasmid mediated dissemination across bacterial populations.

Conclusion: The study demonstrates a low prevalence of NDM 1 among UTI isolates in Onitsha. However, the presence of the gene underscores the importance of ongoing surveillance, strict infection control measures, and antimicrobial stewardship to prevent its wider spread. Larger studies are recommended to provide a more comprehensive understanding of the distribution and clinical impact of NDM 1 in Nigeria and similar settings.

NDM 1, urinary tract infections, antimicrobial resistance, PCR, Onitsha.

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