Clinical evaluation of anti-tuberculous glycolipid immunoglobulin G antibody assay for rapid serodiagnosis of pulmonary tuberculosis

Previously we reported the development of a highly sensitive enzyme-linked immunosorbent assay specific for anti-tuberculous glycolipid (anti-TBGL) fo r the rapid serodiagnosis of tuberculosis. In this study, the usefulness of an anti-TBGL antibody assay kit for rapid serodiagnosis was evaluated in a controlled multicenter study. Antibody titers in sera from 318 patients wi th active pulmonary tuberculosis (216 positive for Mycobacterium tuberculos is in smear and/or culture tests and 102 smear and culture negative and cli nically diagnosed), 58 patients with old tuberculosis, 177 patients with ot her respiratory diseases, 156 patients with nonrespiratory diseases, and 45 4 healthy subjects were examined. Sera from 256 younger healthy subjects fr om among the 454 healthy subjects were examined as a control. When the cuto ff point of anti-TBGL antibody titer was determined as 2.0 U/ml, the sensit ivity for active tuberculosis patients was 81.1% and the specificity was 95 .7%. Sensitivity in patients with smear-negative and culture-negative activ e pulmonary tuberculosis was 73.5%. Even in patients with noncavitary minim ally advanced lesions, the positivity rate (60.0%) and the antibody titer ( 4.6 +/- 9.4 U/ml) were significantly higher than those in the healthy group . These results indicate that this assay using anti-TBGL antibody is useful for the rapid serodiagnosis of active pulmonary tuberculosis.