Failure of Livedoid Vasculitis to Respond to Tissue Plasminogen Activator

Recently, low-dose intravenous recombinant tissue plasminogen activator (t-PA) was reported as a safe and effective treatment for refractory livedoid vasculitis,¹ also known as atrophie blanche or PURPLE. (Milstone et al² proposed a unifying terminology for the multiple presentations of patients with the syndrome, PURPLE, for ''painful purpuric ulcers with reticular patterning on the lower extremities.'') Some patients with PURPLE may have defective release of endogenous t-PA or increased levels of t-PA inhibitor in plasma.³ A specific fibrinolytic factor produced by endothelial cells, t-PA, given over a period of days in smaller doses than when given as a single dose for myocardial infarction, might lyse small cutaneous thrombi (which appear to be a major factor in the pathogenesis of PURPLE). Klein and Pittelkow¹ gave 10 mg of t-PA intravenously over a 4-hour period for 14 days with or without aspirin and heparin. Five of six patients were