Low dose danazol is effective in management of erythropoietin induced thrombosis.

Two patients (one male and one female) with end stage renal disease on chronic hemodialysis were treated with recombinant human erythropoietin (r-HuEPO). Both patients developed significant clotting in the vascular access and extracorporeal circuits. Coagulation studies indicated that both patients acquired high levels of tissue-type plasminogen activator inhibitor (PAI) with deficiency in tissue-type plasminogen activator (t-PA) and consequent impaired fibrinolysis. Their fibrinolytic activity was normalized with danazol therapy in doses as low as 2-4 mg/kg given orally once daily. We conclude that r-HuEPO-induced thrombosis is associated with impaired fibrinolysis due to acquired elevation of PAI which can be effectively prevented by small doses of danazol.