Clinical utility of a combination of lipoarabinomannan, 38-kDa, and 16-kDa antigens as a diagnosis tool for tuberculosis

The aim of this study was to evaluate the diagnostic value of tests detecting antibodies against lipoarabinomannan (LAM), 38-kDa, and 16-kDa antigens for Mycobacterium tuberculosis (MTB). Sera from 160 tuberculosis (TB) patients and 150 non-TB healthy controls were subjected to simultaneous detection of antibodies against LAM, 38-kDa, and 16-kDa antigens using protein chips. The diagnostic value of the 3 TB antigens, alone or combined, was evaluated. Results showed that LAM and 38-kDa antigens had the highest positive rates in the TB patients. Tests showing any single positive antibody, 2 positive antibodies, and 3 positive antibodies had a sensitivity of 93.1%, 51.3%, and 15.6%, and a specificity of 81.3%, 96.6%, and 99.3%, respectively. The positive predictive value of tests showing any 2 positive antibodies and 3 positive antibodies was 94.2% and 96.1%, respectively. Combined detection of a selected panel of TB antibodies can improve the positive rates for TB diagnosis and can serve as an important aid to the diagnosis of TB especially extrapulmonary TB.