Preliminary diagnostic performance of the VIDAS(R) TB-IGRA for the detection of Mycobacterium tuberculosis infection and disease

ImportanceAccurate diagnosis of tuberculosis (TB) infection can be achieved with interferon-{gamma} release assays. Their performance can be improved by utilizing fully automated, single-patient formats. ObjectiveEstablish clinical thresholds for a new interferon-{gamma} release assay, the VIDAS(R) TB-IGRA, and compare diagnostic performance in detecting tuberculosis infection and disease with the established QuantiFERON-TB Gold Plus (QFT-Plus). DesignPreliminary diagnostic performance study (October 2nd, 2019-February 20th, 2020). Setting: Multicenter. ParticipantsParticipants were divided into TB disease, high-risk, and low-risk populations. The confirmed TB disease population included 107 patients. The high-risk population included 162 individuals with flagged risk factors on a questionnaire but without objective clinical confirmation of TB. The Low-risk population included 117 healthy blood donors from the French National Blood Bank. ExposuresTuberculosis. Main Outcomes and MeasuresPositive and negative percent agreement (PPA, NPA) were determined between the VIDAS(R) TB-IGRA and QFT-Plus. In the TB disease population, sensitivity was also measured against bacterial culture and PCR. ResultsThe VIDAS(R) TB-IGRA produced fewer indeterminate results than the QFT-Plus (1/107 vs. 23/107) in the TB disease population. One analysis included indeterminate results as false negatives (94 positives and 10 false negatives vs. 56 positives and 48 false negatives), and the VIDAS(R) TB-IGRA exhibited higher sensitivity than the QFT-Plus (90.4% vs. 53.8%) (p<0.0001). Another analysis excluded indeterminate results (76 positives and 4 false negatives vs. 55 positives and 25 false negatives), and the VIDAS(R) TB-IGRA again exhibited higher sensitivity than the QFT-Plus (95.0% vs. 68.8%) (p<0.0001). A 98.2% PPA was calculated between the two tests with this dataset. In the high-risk population, the VIDAS(R) TB-IGRA exhibited a strong PPA (94.4%) with the QFT-Plus. However, a lower than expected NPA was observed (85.2%). In the low-risk population, the VIDAS(R) TB-IGRA demonstrated high specificity (94.9%) and a strong NPA (98.2%) with the QFT-Plus. Conclusions and RelevanceThe fully automated VIDAS(R) TB-IGRA is a promising diagnostic test for both TB infection and disease. It exhibits higher sensitivity while maintaining specificity and produces fewer indeterminate interpretations. Its easy-to-use, single-patient format may lead to increased TB testing to help with the worldwide eradication of the disease. KEY POINTSO_ST_ABSQuestionC_ST_ABSWhat is the diagnostic performance of the VIDAS(R) TB-IGRA in detecting tuberculosis infection and disease? FindingsThe VIDAS(R) TB-IGRA exhibited high sensitivity in individuals with tuberculosis disease (90.4- 95.0%), high specificity in healthy blood donors (94.9%), a high positive percent agreement (PPA) in individuals with a high risk of tuberculosis infection (94.4%), and it produced a low number of indeterminate results (1/386). MeaningThe VIDAS(R) TB-IGRA is a promising diagnostic test for both tuberculosis infection and disease.