{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T06:00:08Z","timestamp":1785218408595,"version":"3.55.0"},"reference-count":34,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:00:00Z","timestamp":1785196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Antibiot."],"abstract":"<jats:p>Tuberculosis (TB) is a global health challenge and is curable, but tools for rapid treatment monitoring are limited. Current methods, like smear microscopy, lack sensitivity, while culture-based approaches require weeks for results and specialized biosafety facilities. This paper presents a comprehensive protocol for the PATHFAST TB LAM Ag assay, a rapid chemiluminescent enzyme immunoassay that quantifies lipoarabinomannan (LAM) mainly in sputum and likely other biological samples within one hour. This protocol details sample collection, heat inactivation for biosafety, and the automated measurement process. Heat inactivation at 100\u00a0\u00b0C for 20 minutes renders samples non-infectious while preserving LAM for detection. The assay demonstrates excellent analytical performance with a detection limit of 6.67 pg\/mL and a linear measurement range of 10.0\u201350,000 pg\/mL. Published clinical evaluation demonstrated 88.8% (95% CI: 80.0\u201394.0%) sensitivity and 100% (95% CI: 83.9\u2013100%) specificity compared to culture, with strong correlation to bacterial load. The PATHFAST TB LAM Ag assay successfully tracks bacterial decline during treatment, with LAM concentration reductions mirroring culture results but available significantly faster. Unlike culture methods that suffer from contamination (4.2-9.6% invalid results), the PATHFAST TB LAM Ag assay consistently provides valid results. This protocol enables implementation of a rapid, quantitative TB treatment monitoring tool that enhances biosafety, reduces turnaround time, and maintains performance comparable to conventional methods, addressing critical needs in both clinical care and drug development settings.<\/jats:p>","DOI":"10.3389\/frabi.2026.1844052","type":"journal-article","created":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T05:34:56Z","timestamp":1785216896000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The PATHFAST TB LAM Ag assay: a validated protocol for quantitative tuberculosis treatment monitoring"],"prefix":"10.3389","volume":"5","author":[{"given":"Yassir Adam","family":"Shuaib","sequence":"first","affiliation":[{"name":"PHC Europe","place":["Breda, Netherlands"]},{"name":"College of Veterinary Medicine, Sudan University of Science and Technology","place":["Khartoum North, Sudan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phane","family":"Coisne","sequence":"additional","affiliation":[{"name":"PHC Europe","place":["Breda, Netherlands"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,28]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3389\/frabi.2025.1574688","article-title":"Quantification of bactericidal activity using the PATHFAST TB LAM Ag assay during the first 14 days of pulmonary tuberculosis treatment","volume":"4","author":"Akinaga","year":"2025","journal-title":"Front. Antibiot."},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.00629-24","article-title":"Development and preliminary evaluation toward a new tuberculosis treatment monitoring tool: the PATHFAST TB LAM Ag assay","volume":"62","author":"Akinaga","year":"2024","journal-title":"J. Clin. Microbiol."},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1002\/14651858.cd011420.pub3","article-title":"Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in people living with HIV","volume":"10","author":"Bjerrum","year":"2019","journal-title":"Cochrane Database Syst. Rev."},{"key":"B4","volume-title":"Tuberculosis diagnostics pipeline","author":"Branigan","year":"2025"},{"key":"B5","doi-asserted-by":"publisher","first-page":"852","DOI":"10.1016\/s1473-3099(19)30001-5","article-title":"Novel lipoarabinomannan point-of-care tuberculosis test for people with HIV: a diagnostic accuracy study","volume":"19","author":"Broger","year":"2019","journal-title":"Lancet Infect. Dis."},{"key":"B6","volume-title":"Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures","year":"2012"},{"key":"B7","doi-asserted-by":"publisher","first-page":"2321","DOI":"10.1128\/jcm.42.5.2321-2325.2004","article-title":"Meta-analysis of BACTEC MGIT 960 and BACTEC 460 TB, with or without solid media, for detection of mycobacteria","volume":"42","author":"Cruciani","year":"2004","journal-title":"J. Clin. Microbiol."},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.01269-25","article-title":"Clinical evaluation of the diagnostic performances and treatment monitoring of the new PATHFAST TB LAM Ag assay in sputum specimens of patients with tuberculosis or with nontuberculous mycobacteria pulmonary disease","volume":"63","author":"Fouchet","year":"2025","journal-title":"J. Clin. Microbiol."},{"key":"B9","doi-asserted-by":"publisher","first-page":"2042","DOI":"10.1016\/s0140-6736(07)60284-0","article-title":"Diagnosis of smear-negative pulmonary tuberculosis in people with HIV infection or AIDS in resource-constrained settings: informing urgent policy changes","volume":"369","author":"Getahun","year":"2007","journal-title":"Lancet"},{"key":"B10","doi-asserted-by":"publisher","first-page":"1577","DOI":"10.1056\/nejmoa1407426","article-title":"Four-month moxifloxacin-based regimens for drug-sensitive tuberculosis","volume":"371","author":"Gillespie","year":"2014","journal-title":"N. Engl. J. Med."},{"key":"B11","doi-asserted-by":"publisher","first-page":"730","DOI":"10.2471\/blt.23.290901","article-title":"Target product profiles: tests for tuberculosis treatment monitoring and optimization","volume":"101","author":"Gupta-Wright","year":"2023","journal-title":"Bull. World Health Organ."},{"key":"B12","doi-asserted-by":"publisher","first-page":"1708","DOI":"10.1038\/s41591-018-0224-2","article-title":"A patient-level pooled analysis of treatment-shortening regimens for drug-susceptible pulmonary tuberculosis","volume":"24","author":"Imperial","year":"2018","journal-title":"Nat. Med."},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.1002780","article-title":"Lipoarabinomannan in sputum to detect bacterial load and treatment response in patients with pulmonary tuberculosis: Analytic validation and evaluation in two cohorts","volume":"16","author":"Kawasaki","year":"2019","journal-title":"PloS Med."},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1183\/13993003.01259-2019","article-title":"Diagnostic sensitivity of SILVAMP TB-LAM (FujiLAM) point-of-care urine assay for extra-pulmonary tuberculosis in people living with HIV","volume":"55","author":"Kerkhoff","year":"2020","journal-title":"Eur. Respir. J."},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1186\/s41182-026-00910-0","article-title":"Longitudinal urinary LAM measurements in pulmonary tuberculosis patients: preliminary observations","volume":"54","author":"Kolokotroni","year":"2026","journal-title":"Trop. Med. Health"},{"key":"B16","doi-asserted-by":"publisher","first-page":"180","DOI":"10.1093\/trstmh\/trw008","article-title":"Detection of lipoarabinomannan (LAM) in urine is indicative of disseminated TB with renal involvement in patients living with HIV and advanced immunodeficiency: evidence and implications","volume":"110","author":"Lawn","year":"2016","journal-title":"Trans. R. Soc Trop. Med. Hyg."},{"key":"B17","doi-asserted-by":"publisher","first-page":"67","DOI":"10.1186\/s12916-017-0822-8","article-title":"Diagnostic accuracy, incremental yield and prognostic value of Determine TB-LAM for routine diagnostic testing for tuberculosis in HIV-infected patients requiring acute hospital admission in South Africa: a prospective cohort","volume":"15","author":"Lawn","year":"2017","journal-title":"BMC Med."},{"key":"B18","doi-asserted-by":"publisher","first-page":"201","DOI":"10.1016\/s1473-3099(11)70251-1","article-title":"Diagnostic accuracy of a low-cost, urine antigen, point-of-care screening assay for HIV-associated pulmonary tuberculosis before antiretroviral therapy: a descriptive study","volume":"12","author":"Lawn","year":"2012","journal-title":"Lancet Infect. Dis."},{"key":"B19","doi-asserted-by":"publisher","first-page":"407","DOI":"10.1016\/j.tube.2012.05.009","article-title":"Rapid detection of Mycobacterium tuberculosis biomarkers in a sandwich immunoassay format using a waveguide-based optical biosensor","volume":"92","author":"Mukundan","year":"2012","journal-title":"Tuberculosis (Edinb)"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.02100-21","article-title":"High mycobacterium tuberculosis bacillary loads detected by tuberculosis molecular bacterial load assay in patient stool: a potential alternative for nonsputum diagnosis and treatment response monitoring of tuberculosis","volume":"10","author":"Musisi","year":"2022","journal-title":"Microbiol. Spectr."},{"key":"B21","doi-asserted-by":"publisher","first-page":"62","DOI":"10.1186\/s12879-015-0812-4","article-title":"Predictors and outcomes of mycobacteremia among HIV-infected smear- negative presumptive tuberculosis patients in Uganda","volume":"15","author":"Nakiyingi","year":"2015","journal-title":"BMC Infect. Dis."},{"key":"B22","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1186\/s41182-025-00771-z","article-title":"Evaluation of the PATHFAST TB LAM Ag assay as a treatment monitoring tool for pulmonary tuberculosis in Nairobi, Kenya","volume":"53","author":"Orina","year":"2025","journal-title":"Trop. Med. Health"},{"key":"B23","doi-asserted-by":"publisher","first-page":"S15","DOI":"10.1086\/518656","article-title":"Facing the crisis: improving the diagnosis of tuberculosis in the HIV era","volume":"196","author":"Perkins","year":"2007","journal-title":"J. Infect. Dis."},{"key":"B24","volume-title":"Lipoarabinomannan (LAM) as a biomarker for the diagnosis of tuberculosis","author":"Pichlo","year":"2025"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1016\/j.jinf.2025.106662","article-title":"Lipoarabinomannan (LAM) for the diagnosis of tuberculosis from sputum","volume":"91","author":"Pichlo","year":"2025","journal-title":"J. Infect."},{"key":"B26","doi-asserted-by":"publisher","first-page":"606","DOI":"10.1136\/thoraxjnl-2019-214238","article-title":"Tuberculosis bacillary load, an early marker of disease severity: the utility of tuberculosis Molecular Bacterial Load Assay","volume":"75","author":"Sabiiti","year":"2020","journal-title":"Thorax"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1155\/2018\/8038137","article-title":"Smear microscopy for diagnosis of pulmonary tuberculosis in eastern Sudan","volume":"2018","author":"Shuaib","year":"2018","journal-title":"Tuberc Res. Treat."},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.01338-18","article-title":"A novel sensitive immunoassay targeting the 5-methylthio-d-xylofuranose-lipoarabinomannan epitope meets the WHO's performance target for tuberculosis diagnosis","volume":"56","author":"Sigal","year":"2018","journal-title":"J. Clin. Microbiol."},{"key":"B29","doi-asserted-by":"publisher","first-page":"570","DOI":"10.1016\/s1473-3099(06)70578-3","article-title":"Fluorescence versus conventional sputum smear microscopy for tuberculosis: a systematic review","volume":"6","author":"Steingart","year":"2006","journal-title":"Lancet Infect. Dis."},{"key":"B30","doi-asserted-by":"publisher","first-page":"1920","DOI":"10.1016\/s0140-6736(10)60359-5","article-title":"Biomarkers and diagnostics for tuberculosis: progress, needs, and translation into practice","volume":"375","author":"Wallis","year":"2010","journal-title":"Lancet"},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0071116","article-title":"Month 2 culture status and treatment duration as predictors of tuberculosis relapse risk in a meta-regression model","volume":"8","author":"Wallis","year":"2013","journal-title":"PloS One"},{"key":"B32","volume-title":"The End TB Strategy","year":"2015"},{"key":"B33","article-title":"Target Product Profiles for Tests for Tuberculosis Treatment Monitoring and Optimization","year":"2023"},{"key":"B34","article-title":"Global tuberculosis report","year":"2025"}],"container-title":["Frontiers in Antibiotics"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/frabi.2026.1844052\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T05:34:57Z","timestamp":1785216897000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/frabi.2026.1844052\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,28]]},"references-count":34,"alternative-id":["10.3389\/frabi.2026.1844052"],"URL":"https:\/\/doi.org\/10.3389\/frabi.2026.1844052","relation":{},"ISSN":["2813-2467"],"issn-type":[{"value":"2813-2467","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,28]]},"article-number":"1844052"}}