Heparin-induced thrombocytopenia in patients with Philadelphia-negative myeloproliferative disorders and unusual splanchnic or cerebral vein thrombosis

• Published in: Acta haematologica Vol. 123; no. 3; p. 140
• Main Authors: Randi, Maria L, Tezza, Fabiana, Scapin, Margherita, Duner, Elena, Scarparo, Pamela, Scandellari, Raffaella, Fabris, Fabrizio
• Format: Journal Article
• Language: English
• Published: Switzerland 01.01.2010
• Subjects: Adult; Anticoagulants - adverse effects; Anticoagulants - immunology; Anticoagulants - therapeutic use; Budd-Chiari Syndrome - complications; Budd-Chiari Syndrome - drug therapy; Drug Monitoring; Female; Heparin - adverse effects; Heparin - immunology; Heparin - therapeutic use; Heparin, Low-Molecular-Weight - adverse effects; Heparin, Low-Molecular-Weight - immunology; Heparin, Low-Molecular-Weight - therapeutic use; Humans; Intracranial Thrombosis - complications; Intracranial Thrombosis - drug therapy; Male; Middle Aged; Myeloproliferative Disorders - complications; Platelet Count; Polycythemia Vera - complications; Pulmonary Embolism - epidemiology; Pulmonary Embolism - etiology; Pulmonary Embolism - prevention & control; Retrospective Studies; Thrombocythemia, Essential - complications; Thrombocytopenia - chemically induced; Thrombocytopenia - etiology; Thrombocytopenia - immunology; Thrombosis - complications; Thrombosis - drug therapy; Time Factors; Young Adult
• DOI: 10.1159/000280466

Philadelphia-negative myeloproliferative disorders (Ph-MPD) are common causes of unusual splanchnic or cerebral vein thrombosis, which is treated with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH). Heparin-induced thrombocytopenia (HIT) is a dangerous potential complication of this therapy, but it has rarely been reported in Ph-MPD. We retrospectively reviewed clinical records of 29 patients with Ph-MPD who have been treated with UFH or LMWH for unusual splanchnic or cerebral vein thrombosis (3 cerebral sinus, 6 portal and 20 hepatic vein). The goal of the study was to determine the occurrence of new thrombotic events during heparin therapy secondary to HIT (HITT). During heparin therapy, 5 out of the 29 patients (17%) developed a new thrombotic episode (pulmonary embolism) with a high clinical probability of HIT based on the 4 T's score even though not all the patients developed 'true' thrombocytopenia. A diagnosis of HIT was established in 2 patients (6.8%) through the presence of heparin-related antibodies. Ph-MPD patients on heparin warrant careful monitoring and HIT has to be suspected whenever platelet counts drop or a new thrombosis is detectable.