{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T08:00:53Z","timestamp":1775548853376,"version":"3.50.1"},"posted":{"date-parts":[[2026,4,3]]},"group-title":"Pediatrics","reference-count":27,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T00:00:00Z","timestamp":1775174400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,4,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>Tuberculosis (TB) is a significant cause of morbidity and mortality in children and adolescents, causing 172,000 deaths in 2024 in children and adolescents worldwide. Diagnostic challenges are pronounced in pediatrics, in which collecting respiratory specimens is challenging and TB is often paucibacillary, leading to delayed diagnosis and increased mortality. We describe the protocol and methodology of the Pediatric TB Diagnostic (PDTBDx) cohort, a study with the primary aim of evaluating non-sputum-based TB diagnostics for diagnosis and treatment response in children. This is a prospective observational cohort study of &gt;400 children recruited from inpatient and outpatient clinical sites in Nairobi, Kenya. Children &lt;15 years presenting to study clinical sites with TB symptoms will be considered for enrollment as symptomatic participants. Enrolled participants will undergo rigorous clinical assessment and longitudinal follow-up to ensure appropriate diagnostic classification by NIH consensus statement guidelines for pediatric TB. Baseline evaluation includes symptom assessment, chest x-ray, HIV testing, respiratory TB culture and GeneXpert Ultra, and urine LAM. Subsequent visits occur at week 2, months 1, 2, 4, 6,12 and 24. Blood and urine specimens will be collected at baseline and at follow-up visits for storage for evaluation of novel diagnostic assays, including exosome-based and CRISPR-based TB biomarkers. This large, prospective cohort of pediatric participants with and without TB follows a consistent and rigorous protocol for diagnosing childhood TB, in concordance with internationally recognized guidelines. Assays evaluated in PDTBDx will guide improved diagnostic strategies for pediatric TB.<\/jats:p>","DOI":"10.64898\/2026.04.01.26350011","type":"posted-content","created":{"date-parts":[[2026,4,4]],"date-time":"2026-04-04T00:00:16Z","timestamp":1775260816000},"source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of non-sputum-based diagnostics for pediatric tuberculosis: the Pediatric TB Diagnostic (PDTBDx) cohort protocol"],"prefix":"10.64898","author":[{"given":"Brendan","family":"Mullen","sequence":"first","affiliation":[{"name":"Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joy","family":"Githua","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA"},{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"},{"name":"Department of Medical Microbiology and Immunology, University of Nairobi, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jaclyn N.","family":"Escudero","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington, Seattle, WA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jerphason","family":"Mecha","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"},{"name":"Department of Mathematics, University of Nairobi, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lucy","family":"Kijaro","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maureen","family":"Ndunge","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Moses","family":"Muriithi","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isaac","family":"Kibet","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Grace","family":"John-Stewart","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA"},{"name":"Department of Global Health, University of Washington, Seattle, WA, USA"},{"name":"Department of Epidemiology, University of Washington, Seattle, WA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Maleche-Obimbo","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington, Seattle, WA, USA"},{"name":"Department of Paediatrics and Child Health, University of Nairobi, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Videlis","family":"Nduba","sequence":"additional","affiliation":[{"name":"Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sylvia M.","family":"LaCourse","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA"},{"name":"Department of Global Health, University of Washington, Seattle, WA, USA"},{"name":"Department of Epidemiology, University of Washington, Seattle, WA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"54368","reference":[{"key":"2026040700100504000_2026.04.01.26350011v1.1","unstructured":"Global Tuberculosis Report 2025. 1st ed. 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