{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T14:09:03Z","timestamp":1786975743121,"version":"build-2736575974"},"reference-count":31,"publisher":"American Medical Association (AMA)","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"\n Importance<\/jats:title>\n Heparin-induced thrombocytopenia (HIT) is a life-threatening condition that requires urgent diagnostic clarification. However, knowledge of the diagnostic utility of the recommended diagnostic tests is limited in clinical practice.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To evaluate the current diagnostic practice for managing the suspicion of HIT.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n This prospective diagnostic study was conducted from January 2018 to May 2021 among consecutive patients with suspected HIT from 11 study centers in Switzerland, Germany, and the United States. Detailed clinical data and laboratory information were recorded. Platelet factor 4\/heparin antibodies were quantified using an automated chemiluminescent immunoassay (CLIA). A washed-platelet heparin-induced platelet activation (HIPA) test was used as a reference standard to define HIT.<\/jats:p>\n <\/jats:sec>\n \n Exposures<\/jats:title>\n Suspicion of HIT.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n The primary outcome was the diagnostic accuracy of the 4Ts score, the CLIA, and the recommended algorithm serially combining both tests.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Of 1448 patients included between 2018 and 2021, 1318 were available for the current analysis (median [IQR] age, 67 [57-75] years; 849 [64.6%] male). HIPA was positive in 111 patients (prevalence, 8.4%). The most frequent setting was intensive care unit (487 [37.0%]) or cardiovascular surgery (434 [33.0%]). The 4Ts score was low risk in 625 patients (46.8%). By 2\u2009\u00d7\u20092 table, the numbers of patients with false-negative results were 10 (9.0%; 4Ts score), 5 (4.5%; CLIA), and 15 (13.5%; recommended diagnostic algorithm). The numbers of patients with false-positive results were 592 (49.0%; 4Ts score), 73 (6.0%; CLIA), and 50 (4.1%; recommended diagnostic algorithm), respectively.<\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n In this diagnostic study of patients suspected of having HIT, when the recommended diagnostic algorithm was used in clinical practice, antibody testing was required in half the patients. A substantial number of patients were, however, still misclassified, which could lead to delayed diagnosis or overtreatment. Development of improved diagnostic algorithms for HIT diagnosis should be pursued.<\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2024.3786","type":"journal-article","created":{"date-parts":[[2024,3,26]],"date-time":"2024-03-26T11:26:19Z","timestamp":1711452379000},"page":"e243786","source":"Crossref","is-referenced-by-count":18,"title":["Accuracy of Diagnosing Heparin-Induced Thrombocytopenia"],"prefix":"10.1001","volume":"7","author":[{"given":"Emil List","family":"Larsen","sequence":"first","affiliation":[{"name":"Department of Clinical Biochemistry, Copenhagen University Hospital\u2013Rigshospitalet, Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henning","family":"Nilius","sequence":"additional","affiliation":[{"name":"Department of Clinical Chemistry, Inselspital, Bern University Hospital, Bern, Switzerland"},{"name":"Graduate School for Health Sciences, University of Bern, Bern, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan-Dirk","family":"Studt","sequence":"additional","affiliation":[{"name":"Division of Medical Oncology and Hematology, University Hospital Zurich, Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dimitrios A.","family":"Tsakiris","sequence":"additional","affiliation":[{"name":"Diagnostic Haematology, Basel University Hospital, Basel, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Greinacher","sequence":"additional","affiliation":[{"name":"Department of Transfusion Medicine, Institute of Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Mendez","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Kantonsspital Aarau, Aarau, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adrian","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Institute of Laboratory Medicine and Clinic of Medical Oncology and Hematology, Municipal Hospital Zurich Triemli, Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Walter A.","family":"Wuillemin","sequence":"additional","affiliation":[{"name":"Division of Hematology and Central Hematology Laboratory, Cantonal Hospital of Lucerne and University of Bern, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhard","family":"Gerber","sequence":"additional","affiliation":[{"name":"Clinic of Hematology, Oncology Institute of Southern Switzerland, Bellinzona, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prakash","family":"Vishnu","sequence":"additional","affiliation":[{"name":"Fred Hutchinson Cancer Center, University of Washington, Seattle"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lukas","family":"Graf","sequence":"additional","affiliation":[{"name":"Cantonal Hospital of St Gallen, St Gallen, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johanna A.","family":"Kremer Hovinga","sequence":"additional","affiliation":[{"name":"Department of Hematology and Central Hematology Laboratory, Inselspital, Bern University Hospital, Bern, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jens P.","family":"Goetze","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, Copenhagen University Hospital\u2013Rigshospitalet, Copenhagen, Denmark"},{"name":"Department of Biomedical Sciences, Faculty of Health, Copenhagen University, Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tamam","family":"Bakchoul","sequence":"additional","affiliation":[{"name":"Centre for Clinical Transfusion Medicine, University Hospital of T\u00fcbingen, T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Nagler","sequence":"additional","affiliation":[{"name":"Department of Clinical Chemistry, Inselspital, Bern University Hospital, Bern, Switzerland"},{"name":"University of Bern, Bern, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","published-online":{"date-parts":[[2024,3,26]]},"reference":[{"issue":"5","key":"zoi240165r1","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1016\/S0002-9343(96)00258-6","article-title":"A 14-year study of heparin-induced thrombocytopenia.","volume":"101","author":"Warkentin","year":"1996","journal-title":"Am J Med"},{"issue":"1","key":"zoi240165r2","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1002\/(SICI)1096-8652(199709)56:1<12::AID-AJH3>3.0.CO;2-5","article-title":"Heparin-induced thrombocytopenia with thrombosis: incidence, analysis of risk 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TORADI-HIT algorithm. Accessed February 19, 2024. https:\/\/toradi-hit.dbmr.unibe.ch\/"}],"container-title":["JAMA Network Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/jamanetwork.com\/journals\/jamanetworkopen\/articlepdf\/2816742\/larsen_2024_oi_240165_1710778707.79012.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,11,14]],"date-time":"2024-11-14T20:52:21Z","timestamp":1731617541000},"score":1,"resource":{"primary":{"URL":"https:\/\/jamanetwork.com\/journals\/jamanetworkopen\/fullarticle\/2816742"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,3,26]]},"references-count":31,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2024,3,4]]}},"URL":"https:\/\/doi.org\/10.1001\/jamanetworkopen.2024.3786","relation":{},"ISSN":["2574-3805"],"issn-type":[{"value":"2574-3805","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,3,26]]}}}