EC Microbiology

Background: The SD MPT64TB Ag Kit is a newly developed, rapid immunochromatographic test that utilizes a mouse monoclonal antibody against the MPT64 antigen to detect Mycobacterium tuberculosis (MTB) isolates. This enables the rapid identification of MTB in cultured samples. Developed by SD Bioline in South Korea, the kit demonstrates varying predictive values, types, and specificities. It provides both positive and negative detection results, along with specificity and range parameters.

Methods: In laboratories with limited resources, this rapid method for confirming Mycobacterium tuberculosis (M. tuberculosis) culture isolates is reliable, efficient, and cost-effective. The broth consisted of LJ (Löwenstein-Jensen) broth, twelve non-mycobacterial isolates, twelve nontuberculous mycobacteria (NTM) isolates, and forty-four culture isolates of Mycobacterium tuberculosis. The SD Bioline immunochromatography (ICT) assay kit was used to detect the presence of Mycobacterium tuberculosis in five sputum and pus samples using the MPT64 antigen. The MPT64 antigen band was detected in the H37Rv strain as a positive reference control.

Results: All 54 Mycobacterium tuberculosis (MTB) isolates tested also exhibited a similar band, indicating 100% sensitivity. The test kit demonstrated 100% specificity, as no MPT64 band was observed in any of the non-MTB test isolates. In terms of both positive and negative predictive values, the PPV and NPV are 100%.

Conclusion: The global epidemic of tuberculosis persists. For precise drug susceptibility testing, Mycobacterium tuberculosis (M. tuberculosis) culture isolates must be identified quickly. The MPT64 TB Ag detection ICT kit provides a quick and accurate substitute for molecular identification techniques.

Keywords: MPT64 Antigen; Mycobacterium tuberculosis; Rapid Diagnosis; Immunochromatographic Test (ICT)

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