PREVAIL VIIIa: Valutazione dei metodi di screening dell'infezione da tubercolosi latente nelle persone affette da infezione retrovirale in Liberia

Study Description:

This is a prospective study to compare the interferon-gamma release assay (IGRA) and tuberculin skin test (TST) as latent tuberculosis infection (LTBI) screening tests in people living with HIV in Liberia. Participants will be co-enrolled on the ongoing HONOR (A CoHOrt Clinical, Viral, and ImmuNOlogic Monitoring Study of People Living with Retroviral Infection in Liberia) study. A TST will be administered to eligible participants who are being screened by IGRA on HONOR. Since there is no gold standard for diagnosing LTBI, the results of each method will be compared to evaluate whether there is no difference in the probability of testing positive, assess the operational functionality in the clinic and lab, and determine whether one test can be used with greater sensitivity assuming comparable specificity.

In an extension phase, participants who had a positive TST and/or IGRA result will be offered an opportunity to return for an optional assessment by follow-up chest x-ray, non-contrast chest computed tomography (CT) scanning, sputum collection, and phlebotomy. This will involve an additional visit (Visit 4), to occur after completion of the primary phase (Visit 3). The visit may occur in conjunction with (ie, the same day as or within 4 weeks of) a main HONOR study visit, and results of blood tests collected under the main HONOR study will be reviewed. For participants who have already completed the main HONOR study or do not have an upcoming HONOR visit scheduled, a new visit (ie, HONOR TB Visit 4) will be scheduled for this HONOR TB extension study, and a blood draw will also be performed.

Objectives:

Primary Objective: Assess the sensitivity of the IGRA and TST as LTBI screening tools in people living with HIV in Liberia.

Secondary Objective: Assess the operational functionality of the IGRA and TST in Liberia.

Exploratory Objective: Investigate testing approaches, including follow-up chest x-ray imaging, high-resolution chest CT imaging, and performance on sputum of the Mycobacterium tuberculosis (MTB) complex/rifampin (RIF) nucleic acid amplification test (NAAT), to improve diagnosis of stage-specific TB infection by examining how classification of TB status is associated with biomarker levels (only for participants with a positive TST and/or IGRA).

Endpoints:

Primary Endpoint: Frequency of positive results using the IGRA and TST.

Secondary Endpoint: Proportion of each test type successfully completed and the result determined.

Exploratory Endpoint: Repeat chest x-ray assessment, non-contrast chest CT assessment, sputum analysis by MTB/RIF NAAT assay, and analysis of serum by a CRISPR-Mtb-cfDNA assay.