Karina Althaus1, Andreas Straub2, Helene Häberle2, Peter Rosenberger2, Oleg Hidiatov3, Stefanie Hammer4, Stefanie Nowak-Harnau4, Sigrid Enkel4, Reimer Riessen5, Tamam Bakchoul6. 1. Center for Clinical Transfusion Medicine, University of Tübingen, Tübingen, Germany; Transfusion Medicine, Medical Faculty of Tübingen, Tübingen, Germany. 2. Department of Anesthesiology and Intensive Care Medicine, University of Tübingen, Tübingen, Germany. 3. Transfusion Medicine, Medical Faculty of Tübingen, Tübingen, Germany. 4. Center for Clinical Transfusion Medicine, University of Tübingen, Tübingen, Germany. 5. Medical Intensive Care Unit, Department of Medicine, University of Tübingen, Tübingen, Germany. 6. Center for Clinical Transfusion Medicine, University of Tübingen, Tübingen, Germany; Transfusion Medicine, Medical Faculty of Tübingen, Tübingen, Germany. Electronic address: tamam.bakchoul@med.uni-tuebingen.de.
Abstract
BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a serious drug induced reaction that may be associated with life threatening complications. Platelet-activating antibodies directed against platelet factor 4 (PF4)/heparin complexes cause the disease. The diagnosis of HIT is challenging, as thrombocytopenia is a frequent finding in intensive care (ICU) patient population, especially during extracorporeal membrane oxygenation. OBJECTIVE: To investigate the performance of a diagnostic algorithm for HIT in ICU patients. METHODS: ICU patients who developed thrombocytopenia or thrombosis under heparin treatment were included in this study. The pretest probability for HIT was estimated using the 4Ts-score and patient's sera were tested using two rapid immunoassays (RA) LFI-HIT and PaGIA (from Milenia Biotec and DiaMed), and within 72 h using the IgG enzyme immunoassay (EIA) from Hyphen and the heparin induced platelet activation assay (HIPA). RESULTS: 392 consecutive ICU patients with suspected HIT were enrolled in this study, of whom 83/392 (21.2%) patients had extracorporeal circulation. Sera from 120/392 (30.6%) and 98/392 (25.0%) patients revealed positive results in RA and IgG EIA, respectively. The HIPA test revealed heparin-dependent platelet activation in a total of 15/392 (3.8%) ICU patients (3 medical and 12 surgical patients). In addition, sera from 7 patients revealed indeterminate HIPA results, of whom 2 patients had a clinical course compatible with HIT. CONCLUSIONS: Data from our study confirm the high frequency of IgG PF4/heparin antibodies in ICU patients under unfractionated heparin and shows that the combination of 4Ts-score and RA does not reduce the laboratory overinvestigation for HIT in these patients.
BACKGROUND:Heparin-induced thrombocytopenia (HIT) is a serious drug induced reaction that may be associated with life threatening complications. Platelet-activating antibodies directed against platelet factor 4 (PF4)/heparin complexes cause the disease. The diagnosis of HIT is challenging, as thrombocytopenia is a frequent finding in intensive care (ICU) patient population, especially during extracorporeal membrane oxygenation. OBJECTIVE: To investigate the performance of a diagnostic algorithm for HIT in ICU patients. METHODS: ICU patients who developed thrombocytopenia or thrombosis under heparin treatment were included in this study. The pretest probability for HIT was estimated using the 4Ts-score and patient's sera were tested using two rapid immunoassays (RA) LFI-HIT and PaGIA (from Milenia Biotec and DiaMed), and within 72 h using the IgG enzyme immunoassay (EIA) from Hyphen and the heparin induced platelet activation assay (HIPA). RESULTS: 392 consecutive ICU patients with suspected HIT were enrolled in this study, of whom 83/392 (21.2%) patients had extracorporeal circulation. Sera from 120/392 (30.6%) and 98/392 (25.0%) patients revealed positive results in RA and IgG EIA, respectively. The HIPA test revealed heparin-dependent platelet activation in a total of 15/392 (3.8%) ICU patients (3 medical and 12 surgical patients). In addition, sera from 7 patients revealed indeterminate HIPA results, of whom 2 patients had a clinical course compatible with HIT. CONCLUSIONS: Data from our study confirm the high frequency of IgG PF4/heparin antibodies in ICU patients under unfractionated heparin and shows that the combination of 4Ts-score and RA does not reduce the laboratory overinvestigation for HIT in these patients.
Authors: Matthias Lubnow; Johannes Berger; Roland Schneckenpointner; Florian Zeman; Dirk Lunz; Alois Philipp; Maik Foltan; Karla Lehle; Susanne Heimerl; Christina Hart; Christof Schmid; Christoph Fisser; Thomas Müller Journal: PLoS One Date: 2022-08-08 Impact factor: 3.752