Utility of nucleic acid amplification test in the detection of tuberculosis in biological fluids from suspected TB patients in a cardiovascular center in the Philippines.

BACKGROUND: TB NAAT is highly sensitive and can therefore be a helpful tool used in confirming M. tuberculosis. In a prospective study, we evaluated the utility of TB NAAT in the detection of tuberculosis in biological fluids from suspected TB patients. METHODS: We compared tuberculosis nucleic acid amplification test and acid-fast bacilli smears with Lowenstein-Jensen culture, from patients with a clinical suspicion of tuberculosis disease. We calculated the sensitivity, specificity, PPV and NPV. RESULTS: Using the Lowenstein-Jensen culture as the gold standard for detection of Mycobacterium tuberculosis, the TB-NAAT showed sensitivity of 66.67 %, specificity of 93.67 %, and gave a positive predictive value of 44.44 %. CONCLUSION: We conclude that the TB-NAAT is a quick and consistent diagnostic test for TB detection. However, due to a comparably lower sensitivity than other previous studies, the utility of TB-NAAT alone may not be sufficient in the screening of TB patients. Likewise, the TB-NAAT cannot detect non-tuberculous mycobacteria, for which additional analysis may be needed.