Is interleukin-2 an optimal marker for diagnosing tuberculosis infection? A systematic review and meta-analysis

Background Latent tuberculosis infection (LTBI) is a huge reservoir for the deadlier TB disease. Accurate identification of LTBI is a key strategy to eliminate TB. Therefore, a systematic review and meta-analysis approach was used to assess diagnostic potential of IL-2 for LTBI. Methods PubMed, Web of Science, the Cochrane Library and Embase were searched. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the summary receiver operating characteristic curve (AUROC) and hierarchical summary receiver operating characteristic curve (HSROC) were estimated by bivariate and HSROC models. Results Twenty-seven studies including 1404 participants and 1986 samples met the inclusion criteria. The pooled sensitivity, specificity, PLR, NLR, DOR and AUROC of IL-2 were separately as 87%, 98%, 34.78, 0.14, 256.41 and 0.98, indicating a very powerful differentiating ability of IL-2 for LTBI from non-TB controls. For differentiating ATB from LTBI, the pooled sensitivity, specificity, PLR, NLR, DOR and AUROC of IL-2 were 83%, 76%, 3.41, 0.22, 15.47 and 0.87, respectively, suggesting a good differentiating ability of IL-2. Conclusions These findings showed that IL-2 is a powerful marker for differentiating LTBI from non-TB controls and a good marker for differentiating ATB from LTBI individuals.