Incidence and clinical relevance of heparin-induced antibodies in patients with deep vein thrombosis treated with unfractionated or low-molecular-weight heparin.
The frequency of heparin-induced thrombocytopenia (HIT) varies between different clinical treatment settings and remains unknown for patients treated with unfractionated (UFH) or low-molecular-weight heparin (LMWH) because of deep vein thrombosis. In this multicentre, open-label study, 1137 patients with deep vein thrombosis were randomly assigned to UFH for 5-7 d, reviparin, a LMWH, for 5-7 d (short-treated group) or reviparin for 28 d (long-treated group). Heparin-platelet factor 4 antibodies (HPF4-A) were determined on d 5-7 and d 21. Heparin-induced thrombocytopenia was defined by clinical evaluation. Two patients in the UFH group (incidence: 0.53%, 95% confidence interval (CI): 0.06-1.91) and two patients in the long-treated LMWH group (incidence: 0.53%, 95% CI: 0.06-1.92) had HIT, while no HIT was observed in the short-treated LMWH group. Pulmonary embolism developed in one of the HIT-patients, who had HPF4-A and was treated with UFH. On d 5-7 the incidence of HPF4-A was 9.1% in the UFH group, 2.8% in the short-treated LMWH group and 3.7% in the long-treated LMWH group, with a significant increase to 20.7% in the UFH group and to 7.5% in the long-treated LMWH group on d 21. Therefore the incidence of HPF4-A and heparin-induced thrombocytopenia was lower in patients treated with LMWH compared with UFH for the same duration of treatment.
Lindhoff-Last
Edelgard
E
Department of Internal Medicine, Division of Angiology, University Hospital Frankfurt, Knoll AG, Ludwigshafen, Germany. Lindhoff-Last@em.uni-frankfurt.de
Nakov
Roumen
R
Misselwitz
Frank
F
Breddin
Hans-Klaus
HK
Bauersachs
Rupert
R
D000925:Anticoagulants / Q000627:therapeutic use*; D001323:Autoantibodies / Q000097:blood*; D004334:Drug Administration Schedule; D005260:Female; D006493:Heparin / Q000009:adverse effects / Q000276:immunology / Q000627:therapeutic use*; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D010978:Platelet Factor 4 / Q000276:immunology*; D011446:Prospective Studies; D013921:Thrombocytopenia / Q000139:chemically induced; D013997:Time Factors; D020246:Venous Thrombosis / Q000188:drug therapy* / Q000276:immunology*
D000925:Anticoagulants; D001323:Autoantibodies; D006495:Heparin, Low-Molecular-Weight; D010978:Platelet Factor 4; C094240:reviparin; D006493:Heparin