[Skin necroses, thrombocytopenia and deep venous thrombosis in subcutaneous thromboembolism prophylaxis with heparin: heparin-induced thrombocytopenia (HIT) type II].

We present a 52-year-old woman who developed a heparin-induced thrombocytopenia type II (HIT II) with deep vein thrombosis, thrombocytopenia and skin necrosis 7 days after initiating subcutaneous prophylaxis with 2 x 5000 U of unfractionated heparin. The platelet count fell from an initial value of 233 x 10(9)/L to 57 x 10(9)/L and normalized within 3 days after stopping heparin. Oral phenprocoumon was started, and her further course was uneventful. The pathogenesis and diagnosis of HIT II is illustrated, and the possible therapeutic options are discussed. To prevent this potentially lethal complication, it is important to begin oral anticoagulation on the first or second day of heparinization, and to stop heparin if the INR-value has been within a therapeutic range for 2 consecutive days. Platelet counts must be checked after 5 to 7 days of heparin therapy. In the case of suspected HIT II, a diagnostic test has to be performed, the heparin must be stopped, and an anticoagulation with either danaparoid or lepirudin is recommended.