Abstract
Diagnosis and proper management of latent tuberculosis infection (LTBI) are important components in reducing the number of patients and deaths from tuberculosis (TB). The diagnosis of LTBI using the interferon-gamma release assays (IGRAs) to detect interferon-gamma in bloods sample has advantages over the tuberculin skin test (TST), but the currently used test kits are expensive and require enzyme-linked immunosorbent assay (ELISA), making it complicate and unsuitable for a district or provincial laboratory use. The QIAreach QuantiFERON-TB (QIAREACH-TB) is a novel blood-based test that uses lateral flow immunoassay (LFA) and digital fluorescence signal measurement to detect interferon-gamma. This study aimed to evaluate the QIAREACH-TB for the diagnosis of LTBI using a whole-blood sample compared to the QuantiFERON-TB Gold Plus (QFT-Plus). Blood samples were collected from 154 healthcare workers (HCWs) and tested for LTBI using the QFT-Plus and QIAREACH-TB. The results showed that the overall percentage agreement (OPA; accuracy) between the QIAREACH-TB and QFT-Plus was 93.46% (95% confidence interval [95% CI]: 88.31-96.82), the positive percent agreement (PPA; sensitivity) was 88.46% (95% CI: 69.85-97.55), and the negative percent agreement (NPA; specificity) was 94.49% (95% CI: 88.97-97.76). In conclusion, the QIAREACH-TB has high agreements with the QFT-Plus, but requires fewer laboratory resources and does not require ELISA, thus making it allows for the expansion of efforts to detect individuals with LTBI following the national TB control strategy.
