Warfarin-induced venous limb gangrene following heparin-induced thrombocytopenia during anticoagulation therapy for deep vein thrombosis and pulmonary thromboembolism

抄録

Heparin-induced thrombocytopenia(HIT) is a complication of anticoagulation therapy using heparin. We report a critical case of HIT during anticoagulation therapy with heparin and warfarin. A 67-year-old man was admitted to our hospital with deep vein thrombosis and pulmonary thromboembolism. Intravenous heparin and oral warfarin were initiated for anticoagulation. Eleven days after starting heparin therapy, the platelet count suddenly decreased to below 50,000/μ l, indicative of type 2 HIT. Twelve days after starting heparin, an above-knee amputation was required for warfarin-induced venous limb gangrene. During anticoagulation therapy with heparin, attention must be paid to the risk of critical HIT. Furthermore, the risk of warfarin causing venous limb gangrene in patients with HIT must be considered.