Figure 1.

Recommended algorithm for accurate and rapid diagnosis of pulmonary tuberculosis in a real-world setting with high prevalence of M. tuberculosis and nontuberculous mycobacterium infections. *Three to four respiratory samples are recommended for AFB smear microscopy, with bronchoalveolar lavage liquid (BALF) preferred. ^†BALF preferred. ^¶T-SPOT^MDC (manufacturer-defined cutoff) has a supplementary role in ruling out pulmonary tuberculosis among AFB^-/Xpert^- patients. ^§TBAg/PHA (ratio of TBAg to PHA spot-forming cells, which is modified method calculating T-SPOT.TB assay results) ≥0.3 has a supplementary role in ruling in pulmonary tuberculosis among AFB^-/Xpert^- patients. AFB, acid-fast bacilli smear; AFB⁺, AFB smear positive; AFB^-, AFB smear negative; Xpert, Xpert MTB/RIF; Xpert⁺, Xpert positive; Xpert^-, Xpert negative; MTB, Mycobacterium tuberculosis; NTM, nontuberculous mycobacterium; T_SPOT, T-SPOT.TB; MDC, manufacturer-defined cutoff; TBAg, Mycobacterium tuberculosis-specific antigens; PHA, phytohaemagglutinin; Sen, sensitivity; PPV, positive predictive value; Spe, specificity.