Warfarin - hudbiverkan. Patienten har blå-röda svullnader under fötterna, värmeökat. Brännande.

Fråga: Warfarin - hudbiverkan. Patienten har blå-röda svullnader under fötterna, värmeökat. Brännande.

Sammanfattning: A variety of skin lesions has been reported as a rare complication of warfarin and dicumarol therapy, including purpura, urticaria, petechiae, ecchymoses, hemorrhagic dermal necrosis and the purple toe.

Since the sympton of blue-red toe of this patient occurred during the continued therapy of warfarin, it could be considered as the cutaneous complication of this drug.

Svar: Apart from the main unwanted adverse effect, that is hypothrombinemia, commonly seen in the anticoagulant therapy, cutaneous lesion has been reported to be a rare complication during dicumarol or warfarin therapy (1). During the forty years since the use of coumarin drugs in 1940, over 170 cases of anticoagulant- induced skin necrosis have been reported (2-8). The incidence of this dermal complication is estimated to be less than one in a 1000 (3). There seems to be no sex difference, but the high number of this complication in the middle-aged seems to be related to the age-range of patients on anticoagulants. The clinical picture and histological examination demonstrate a similar identical dermal lesion and vasculitis for different compounds of the coumarin series, such as warfarin, dicoumarol, and others (2).<br><br>The lesions usually occur within the third to the ninth day after the start of anticoagulant therapy (3,8) involving areas with abundant subcutaneous fat such as buttocks, abdomen, lateral part of flank, thigh and breast (5). They have been classified into 4 general types of skin changes, viz., (1) erythema, petechiae, ecchymoses, and purpura, (2) macular, papular, vesicular, urticarial and purpuric skin eruptions, (3) hemorrhagic dermal necrosis, and/or (4) purple toes (5).<br><br>The pathologic changes include varying degrees of hemorrhages necrosis and acute inflammation. Venules are generally affected, with recent and organizing thrombi in the veins, but arterial involvement is minimal. Necrosis are due to part of a generalized thrombotic process (7,8). The mechanism of pathogenesis of coumarin-induced skin necrosis remains obscure. It has been thought to be due to a direct toxic effect of anticoagulants on the dermavascular loop at the junction of the capillary and precapillary arteriole, resulting in the rupture of capillaries, sludging of blood and subsequent thrombosis in venules (7,8).<div id="referenser" style="display:none;">1 Goodman and Gilman, The pharmacological basis of therapeutics, 5th ed, 1975, sid 1359-1360<br>2 Stavorosky M, Lichtenstein D, Nissim F: Skin petechiae and ecchymoses (vasculitis) due to anticoagulant therapy. Dermatologica 1979; 158: 451-461<br>3 Hardisty CA: Dermal gangrene. A rare complication of warfarin therapy. Postgrad Med J 1978; 54: 123-126<br>4 Faraci PA, Deterling RA Jr, Stein AM, Rheinlander HF, Cleveland RJ: Warfarin induced necrosis of the skin. Surg Gynecol Obstet 1978; 146: 695-700<br>5 Kwong P, Robertts P, Prescott SM, Tikoff G: Dermatitis induced by warfarin. JAMA 1978; 239: 1884-1885<br>6 Meyler/Herxheimer, Side effects of drugs, Annual 1, 1977, s. 264, 267<br>7 Renick AM Jr: Anticoagulant-induced necrosis of skin and subcutaneous tissues: report of two cases and review of the English literature. South Med J 1976; 69: 775-778<br>8 Nalbandian RM, Mader IJ, Barrett JL, Pearce JF, Rupp EC: Petechiae, ecchymoses, and necrosis of skin induced by coumarin congeners. JAMA 1965; 192: 107-112</div>