Positive rates of interferon-γ release assay and tuberculin skin test in detection of latent tuberculosis infection: A systematic review and meta-analysis of 200,000 head-to-head comparative tests

Objective To compare the positive rates of IGRA and TST in detection of LTBI. Methods We searched PubMed, Embase, and the Cochrane Library on March 12, 2022. A random-effects model was used to calculate pooled results. Results We included 458 head-to-head studies. Compared with immunocompetent controls, TST positive rate in immunosuppressed population decreased more than IGRA positive rate (OR 0.36 [95% CI: 0.31 to 0.41] versus 0.53 [0.46 to 0.61]). In immunocompetent BCG-vaccinated individuals, IGRA positive rate in low-TB burden areas was significantly lower than TST positive rate, but the difference was decreased in high-TB burden areas (OR 0.75 [0.60 to 0.94]). Additionally, IGRA positive rate was equal to that of TST in the elderly (OR 0.98 [0.66 to 1.46]). Conclusion TST is more susceptible to immunosuppression than IGRA. The effect of BCG on TST might be weakened in high-TB burden areas, and TST response waned in the elderly. Review registration PROSPERO CRD42020180163.