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Introduction: Tuberculosis (TB) is an important cause of morbidity and mortality among people living with HIV (PLHIV). Current WHO-recommended strategies for diagnosing TB among hospitalized PLHIV rely on symptom screening and disease severity to assess eligibility for urine lipoarabinomannan lateral flow (LF-LAM) and molecular testing. Despite these recommendations, autopsy studies show a large burden of undiagnosed TB among admitted PLHIV. The EXULTANT trial aims to assess the impact of an expanded screening strategy using three specimens (sputum, stool, and urine) for TB diagnosis among PLHIV admitted to hospitals in two high HIV and TB burden African countries., Methods: This is a multicenter, pragmatic, individually randomized controlled trial conducted across eleven hospitals in Tanzania and Mozambique. Participants in the intervention arm will be tested with Xpert MTB/RIF Ultra® from expectorated sputum, stool, and urine samples, with additional urine LF-LAM testing in the first 24 h after hospital admission, irrespective of the presence of the symptoms. The control arm will implement the WHO standard of care recommendations. Hospitalized adults (≥ 18 years) with a confirmed HIV-diagnosis, irrespective of antiretroviral (ART) therapy status or presence of TB symptoms will be assessed for eligibility at admission. Patients with a pre-existing TB diagnosis, those receiving anti-tuberculosis therapy or tuberculosis preventive treatment in the 6 months prior to enrolment, and those transferred from other hospitals will not be eligible. Also, participants admitted for traumatic reasons such as acute abdomen, maternal conditions, scheduled surgery, having a positive SARS-CoV2 test will be ineligible. The primary endpoint is the proportion of participants with microbiologically confirmed TB starting treatment within 3 days of enrolment., Discussion: The EXULTANT trial investigates rapid implementation after admission of a new diagnostic algorithm using Xpert MTB/RIF Ultra® in several non-invasive specimens, in addition to LF-LAM, in hospitalized PLHIV regardless of TB symptoms. This enhanced strategy is anticipated to detect frequently missed TB cases in this population and is being evaluated as an implementable and scalable intervention., Trial Registration: Trial reference number: NCT04568967 (ClinicalTrials.gov) registered on 2020-09-29., (© 2024. The Author(s).)

Background: Despite increasing availability of rapid molecular tests for the diagnosis of tuberculosis in high-burden settings, many people with tuberculosis are undiagnosed. Reliance on sputum as the primary specimen for tuberculosis diagnostics contributes to this diagnostic gap. We evaluated the diagnostic accuracy and additive yield of a novel stool quantitative PCR (qPCR) assay for the diagnosis of tuberculosis in three countries in Africa with high tuberculosis burdens., Methods: We undertook a prospective diagnostic accuracy study in Eswatini, Mozambique, and Tanzania from Sept 21, 2020, to Feb 2, 2023, to compare the diagnostic accuracy for tuberculosis of a novel stool qPCR test with the current diagnostic standard for Mycobacterium tuberculosis DNA detection from sputum and stool, Xpert-MTB/RIF Ultra (Xpert Ultra). Sputum, stool, and urine samples were provided by a cohort of participants, aged 10 years or older, diagnosed with tuberculosis. Participants with tuberculosis (cases) were enrolled within 72 h of treatment initiation for tuberculosis diagnosed clinically or following laboratory confirmation. Participants without tuberculosis (controls) consisted of household contacts of the cases who did not develop tuberculosis during a 6-month follow-up. The performance was compared with a robust composite microbiological reference standard (CMRS)., Findings: The cohort of adolescents and adults (n=408) included 268 participants with confirmed or clinical tuberculosis (cases), 147 (55%) of whom were living with HIV, and 140 participants (controls) without tuberculosis. The sensitivity of the novel stool qPCR was 93·7% (95% CI 87·4-97·4) compared with participants with detectable growth on M tuberculosis culture, and 88·1% (81·3-93·0) compared with sputum Xpert Ultra. The stool qPCR had an equivalent sensitivity as sputum Xpert Ultra (94·8%, 89·1-98·1) compared with culture. Compared with the CMRS, the sensitivity of the stool qPCR was higher than the current standard for tuberculosis diagnostics on stool, Xpert Ultra (80·4%, 73·4-86·2 vs 73·5%, 66·0-80·1; p=0·025 on paired comparison). The qPCR also identified 17-21% additional tuberculosis cases compared to sputum Xpert Ultra or sputum culture. In controls without tuberculosis, the specificity of the stool qPCR was 96·9% (92·2-99·1)., Interpretation: In this study, a novel qPCR for the diagnosis of tuberculosis from stool specimens had a higher accuracy in adolescents and adults than the current diagnostic PCR gold standard on stool, Xpert-MTB/RIF Ultra, and equivalent sensitivity to Xpert-MTB/RIF Ultra on sputum., Funding: National Institutes of Health (NIH) Allergy and Infectious Diseases, and NIH Fogarty International Center., Competing Interests: Declaration of interests CL has received funding for this work from the German Center for Infection Research (DZIF); consulting fees from Insmed; and speakers' honoraria from Insmed, Gilead, GSK, and Janssen outside of the scope of this work. AMM has received honoraria from Janssen for participation in a data and safety monitoring board outside of the scope of this work. All other authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: In 2020, the WHO-approved Molbio Truenat platform and MTB assays to detect Mycobacterium tuberculosis complex (MTB) and resistance to rifampicin directly on sputum specimens. This primary health care center-based trial in Mozambique and Tanzania investigates the effect of Truenat platform/MTB assays (intervention arm) combined with rapid communication of results compared to standard of care on TB diagnosis and treatment initiation for microbiologically confirmed TB at 7 days from enrolment., Methods: The Tuberculosis Close the Gap, Increase Access, and Provide Adequate Therapy (TB-CAPT) CORE trial employs a pragmatic cluster randomized controlled design to evaluate the impact of a streamlined strategy for delivery of Truenat platform/MTB assays testing at primary health centers. Twenty-nine centers equipped with TB microscopy units were selected to participate in the trial. Among them, fifteen health centers were randomized to the intervention arm (which involves onsite molecular testing using Truenat platform/MTB assays, process process optimization to enable same-day TB diagnosis and treatment initiation, and feedback on Molbio platform performance) or the control arm (which follows routine care, including on-site sputum smear microscopy and the referral of sputum samples to off-site Xpert testing sites). The primary outcome of the study is the absolute number and proportion of participants with TB microbiological confirmation starting TB treatment within 7 days of their first visit. Secondary outcomes include time to bacteriological confirmation, health outcomes up to 60 days from first visit, as well as user preferences, direct cost, and productivity analyses., Ethics and Dissemination: TB-CAPT CORE trial has been approved by regulatory and ethical committees in Mozambique and Tanzania, as well as by each partner organization. Consent is informed and voluntary, and confidentiality of participants is maintained throughout. Study findings will be presented at scientific conferences and published in peer-reviewed international journals., Trial Registration: US National Institutes of Health's ClinicalTrials.gov, NCT04568954. Registered 23 September 2020., (© 2024. The Author(s).)