[Heparin-induced thrombocytopenia type II].

Heparin-induced thrombocytopenia type II (HIT type II) is an immunoglobulin-mediated, drug-induced side effect for heparin-treated patients with thromboembolic complications. With an incidence of 1-3 %, mortality of 20 % it and permanent disability for another 20 % is a clinically relevant disorder. With heparin treatment or prophylaxis frequent platelet count monitoring is necessary. With HIT type II the thrombocytopenia is often a harbinger of thromboembolic complications in the venous or arterial system. If HIT type II is suspected, further heparin exposure is to be stopped immediately and another anticoagulant therapy should be started. The two anticoagulant options in Germany are discussed. At the same time the diagnosis should be confirmed by laboratory testing, including testing for cross-reactivity with danaparoid. Further therapy depends on the symptoms. In the case of clinical relevance of this disorder we should think about prophylaxis: strict indications for perioperative prophylaxis only use of low-molecular-weight heparin (LMWH) for routine prophylaxis, use of LMWH for thrombosis treatment and early change to cumarine.