Diagnostic usefulness of a T-cell-based assay in patients with miliary tuberculosis compared with those with lymph node tuberculosis.

Forty-three patients with miliary tuberculosis were evaluated for diagnostic usefulness of enzyme-linked immunospot (ELISPOT) assay. Among noninvasive rapid tests available within 3-5 days, ELISPOT had the highest sensitivity (93%), compared with acid-fast bacilli stain (sputum, 32% and bronchoalveolar lavage, 7%), Mycobacterium tuberculosis polymerase chain reaction (sputum, 53% and bronchoalveolar lavage, 36%), and tuberculin skin test (22%). In comparison with 44 patients with lymph node tuberculosis, the sensitivity of the ELISPOT assay in patients with miliary tuberculosis (93%) was as high as in those with lymph node tuberculosis (95%, P = .63), whereas the sensitivity of the tuberculin skin test was substantially lower in patients with miliary tuberculosis (22%) than in those with lymph node tuberculosis (73%, P < .001).