{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T18:14:21Z","timestamp":1792001661118,"version":"4.4.0"},"reference-count":24,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:00:00Z","timestamp":1769040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>High-sensitivity cardiac troponin assays are susceptible to analytical interferences, including macrotroponin, an immunoglobulin-bound complex that may cause persistent, non-dynamic, and assay-dependent elevations. This paper describes the case of a 74-year-old woman with hypertension who presented with intermittent mild chest discomfort and exertional dyspnea and exhibited persistently elevated but stable cardiac troponin I concentrations over several months, in the absence of clinical, electrocardiographic, or imaging evidence of myocardial injury. Orthogonal testing revealed discordant results across different assay platforms, and polyethylene-glycol (PEG) precipitation resulted in a substantial signal reduction, confirming macrotroponin as the source of assay-dependent analytical interference. Recognizing this phenomenon is crucial to avoid misdiagnosis, unnecessary diagnostic procedures and inappropriate management in patients with isolated troponin elevation. In conclusion, this report provides evidence-based recommendations on the optimal diagnostic strategies and laboratory approaches to adopt in cases of suspected macrotroponin-mediated interference in high-sensitivity cardiac troponin assays.<\/jats:p>","DOI":"10.3390\/ijms27021117","type":"journal-article","created":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T09:16:59Z","timestamp":1769159819000},"page":"1117","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Clinical Impact of Macrotroponin on Immunometric Troponin Assays: A Cross-Analytical Case Evaluation"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9678-0942","authenticated-orcid":false,"given":"Michela","family":"Salvatici","sequence":"first","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica Hospital, 20138 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4068-7607","authenticated-orcid":false,"given":"Chiara","family":"Corrado","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica Hospital, 20138 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Passerini","sequence":"additional","affiliation":[{"name":"Clinical Laboratory with Specialized Areas, IRCCS European Institute of Oncology, 20141 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Gaimarri","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica Hospital, 20138 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Delia Francesca","family":"Sansico","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica Hospital, 20138 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ludovica","family":"Barile","sequence":"additional","affiliation":[{"name":"Cardiology Unit, IRCCS MultiMedica, 20099 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Bandera","sequence":"additional","affiliation":[{"name":"Cardiology Unit, IRCCS MultiMedica, 20099 Milan, Italy"},{"name":"Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5206-540X","authenticated-orcid":false,"given":"Lorenzo","family":"Drago","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica Hospital, 20138 Milan, Italy"},{"name":"Clinical Microbiology and Microbiome Laboratory, Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1373\/clinchem.2016.255109","article-title":"IFCC Task Force on clinical applications of cardiac biomarkers. 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