TABLE 5.
Effect of DM on immunological diagnosis of TB.
| Ref., country, year | Research design | Sample size (n) | Immunological examination: positive in DM patient n (%) | Result | Conclusion |
|---|---|---|---|---|---|
| [166] China, 2022 | Prospective study | DM: 404 |
(1) TST, n = 39 (9.65%) (2) C‐TST, n = 42 (10.40%) (3) IGRA, n = 60 (14.85%) |
The concordance of TST and C‐TST results with IGRA results was 86.39% (349/404) and 92.08% (372/404) with a Kappa coefficient of 0.37 (95% CI 0.24–0.50) and 0.64 (95% CI: 0.53–0.76), respectively. | In patients with T2DM, C‐TST showed higher consistency with IGRA than TST. |
| [167] Portugal, 2022 | Retrospective cohort study |
TB: 727 DM‐TB: 41 |
(1) TST‐5 mm, n = 31 (75.6%) (2) TST‐10 mm, n = 27 (65.8%) (3) IGRA, n = 32 (78.0%) |
IGRA and TST‐5 mm show agreement (kappa, 0.795) (p < 0.001). IGRA and TST‐10 mm show agreement (kappa, 0.585) (p < 0.001). | Comorbidities can lower the sensitivity of individual tests. Combining both tests could enhance the detection of infection cases compared to using either test alone. |
| [168] China, 2010 | Prospective cohort study | DM: 84 | ELISPOT, n = 54 |
The sensitivity of ELISPOT in poorly controlled blood glucose is 77.4% (24/31). The sensitivity of ELISPOT in poorly controlled blood glucose is 90.1% (10/11). |
The negative predictive value of the ELISPOT assay was significantly higher in patients with adequate glycaemic control (90% vs. 56.3%). |
| [169] America, 2015 | Retrospective study |
TB: 300 DM‐TB: 44 |
TST, n = 41 (93.2%) QFT, n = 26 (59.1%) |
TST sensitivity in DM‐TB patients:93.2% (95% CI: 81.8–97.7). QFT sensitivity in DM‐TBpatients:59.1% (95% CI: 44.4–72.3). |
QFT sensitivity was lower than that of TST, especially in patients with DM. |
| [170] Tanzanian, 2014 | Cross‐sectional study | TB: 187 |
DM: Normal glucose tolerance: 126 (67.4%) Pre‐diabetes: 45 (24.1%) Diabetes: 16 (8.6%) QFT result: Negative: 25 (13.4%) Positive: 134 (71.7%) Indeterminate: 28 (15.0%) |
The negative test result was more common among TB patients with pre‐diabetes (OR = 3.1, 95% CI: 1.2–8.2, p = 0.022). The increase of FBG was negatively correlated with IFN‐γ (B‐0.3, 95% CI 0.6–0.03, p = 0.033). |
In patients with diabetes, the effectiveness of IFN‐γ in detecting LTBI may be questionable. |
Abbreviations: C‐TST, creation tuberculin skin test; DM, diabetes mellitus; IGRA, interferon‐gamma (IFN‐γ) release assay; LTBI, latent tuberculosis infection; QFT, QuantiFERON‐TB test; TB, tuberculosis; TST, tuberculin skin test.