TB-Feron Offers a Near-Point-of-Care Option for Tuberculosis Diagnosis
ACCURATE and timely diagnosis of tuberculosis (TB) infection remains a cornerstone for controlling the global TB epidemic. The STANDARD F TB-Feron FIA (TB-Feron) has been evaluated as a near-point-of-care assay, providing clinicians with a potentially faster and more accessible tool for identifying individuals who may benefit from preventive therapy.
Study Design and Methods
A cross-sectional study was conducted at the Vietnam National Lung Hospital between June and December 2024, enrolling 352 participants, with 345 eligible for analysis. The cohort included 95 individuals with microbiologically confirmed pulmonary TB, 200 household contacts of TB patients, and 50 participants with recent negative QFT-Plus results and no known TB exposure. All participants underwent testing with TB-Feron and the reference QuantiFERON TB Gold Plus (QFT-Plus) assay. The study evaluated sensitivity, specificity, inter-test agreement, and reproducibility.
High Sensitivity and Moderate Specificity
TB-Feron demonstrated a sensitivity of 88.4% (95% CI 80.2–94.1) in participants with confirmed TB and a specificity of 70.0% (55.4–82.1) in low-risk participants. Among household contacts, positive and negative agreement with QFT-Plus was 89.2% and 75.4%, respectively, with inter-test agreement of 80.5% (Cohen’s κ = 0.607, P<0.0001). Reproducibility analyses showed stable IFN-γ levels across repeated tests.
Clinical Implications
These findings suggest that TB-Feron is a sensitive near-point-of-care diagnostic tool for TB infection. Its rapid turnaround and simplified workflow could facilitate broader TB screening and improve identification of candidates for preventive therapy. Clinicians should be aware, however, of the assay’s suboptimal specificity, which may lead to a higher rate of false positives compared with QFT-Plus. Further evaluation in diverse clinical settings will clarify its role in routine practice.
Reference
Nguyen HT et al; TBI Testing Team. Diagnostic accuracy of the STANDARD F TB-Feron FIA assay for tuberculosis infection in Vietnam: a cross-sectional study. Clin Infect Dis. 2025; DOI: 10.1093/cid/ciaf561.
