Preliminary diagnostic performance of the VIDAS® TB-IGRA for the detection ofMycobacterium tuberculosisinfection and disease
Authors: Diagbouga Serge , Djibougou Arthur D. , Pease Camille , Alcaide Ariana , Berthoux Audrey , Bruiners Natalie , Cirillo Daniela Maria , Combary Ardjouma , Falchero Nadine , Handler Deborah , Kabore Antoinette , Lardizabal Alfred , Lopes Amanda , Loubet Marissa , Manivet Philippe , Margain Clemence , Meunier Valerie , Mougari Faiza , Onyuka Alberta , Rivoiron Sophie , Sagna Tani , Sanvert Mathilde , Sawadogo Leon , Simpore Jacques , Cambau Emmanuelle , Gennaro Maria Laura 
Published: April 2022

Importance

Accurate diagnosis of tuberculosis (TB) infection can be achieved with interferon-γ release assays. Their performance can be improved by utilizing fully automated, single-patient formats.

Objective

Establish clinical thresholds for a new interferon-γ release assay, the VIDAS® TB-IGRA, and compare diagnostic performance in detecting tuberculosis infection and disease with the established QuantiFERON-TB Gold Plus (QFT-Plus).

Design

Preliminary diagnostic performance study (October 2nd, 2019–February 20th, 2020). Setting: Multicenter.

Participants

Participants 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.

Exposures

Tuberculosis.

Main Outcomes and Measures

Positive and negative percent agreement (PPA, NPA) were determined between the VIDAS® TB-IGRA and QFT-Plus. In the TB disease population, sensitivity was also measured against bacterial culture and PCR.

Results

The VIDAS®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®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® 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® 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® TB-IGRA demonstrated high specificity (94.9%) and a strong NPA (98.2%) with the QFT-Plus.

Conclusions and Relevance

The fully automated VIDAS®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 POINTS

Question

What is the diagnostic performance of the VIDAS® TB-IGRA in detecting tuberculosis infection and disease?

Findings

The VIDAS®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).

Meaning

The VIDAS®TB-IGRA is a promising diagnostic test for both tuberculosis infection and disease.