Positivity rate of QuantiFERON-TB Gold Plustest among candidates for biotherapy and factors influencing results.
Hanane Mezenner, Hiba Ait Hamoudi, Soumia Naamoune, Meriem Abbadi, Meriem Khedimallah, Kafia Belhocine, Samira Zobiri, Yanis Meddour, et al. (10 authors)
SAGE open medicine · 2026-01
Abstract
BACKGROUND: Latent tuberculosis infection, an infection caused by, affects one-quarter of the world's population. The World Health Organization recommends screening for latent tuberculosis infection in at-risk populations to reduce morbidity and mortality risks associated with tuberculosis using the tuberculin skin test and interferon-gamma release assays, including the QuantiFERON-TB Gold Plustest (QTF-Plustest).
OBJECTIVES: This study aimed to assess the place of QTF-Plus test in latent tuberculosis infection screening among a high-risk population.
METHODS: A total of 969 biotherapy candidates were included in the study (52.63% female and 47.36% male; sex ratio = 0.9).
RESULTS: The mean age was 38.29 ± 15.83 years. The frequency of latent tuberculosis infection, according to QTF-Plus test results, was 20.22%. Factors such as age and history of tuberculosis were significantly associated with QTF-Plus test results ( = 0.002 and < 0.0001, respectively). QTF-Plus test and tuberculin skin test were performed simultaneously on 632 patients. A weak agreement between these tests was found (77.50%, Cohen's kappa coefficient of 0.13). However, a good correlation between TB antigen tube 1 and TB antigen tube 2 ( = 0.72, < 0.0001; 95% CI: 0.68-0.74) was observed.
CONCLUSION: Our findings demonstrate that the QTF-Plus test is useful for latent tuberculosis infection screening in a highly vaccinated population with an intermediate prevalence of tuberculosis.