Effects of defibrotide in acute renal failure due to thrombotic microangiopathy.

Thrombotic microangiopathy (TMA) can occur whenever pathogenetic events lead to fibrin deposition in the microcirculation. It has been suggested that intravascular coagulation is important in the development of renal as well as cerebral lesions. The mortality rate in adults varies from 50 to 70%; chronic or progressive renal failure occurs in approximately two thirds of children over 2 years of age. Poor success may be due to therapy being initiated too late or to inappropriate use of antagonistic drugs, or both. In the last 2 years we have treated 8 patients with TMA (5 with thrombotic thrombocytopenic purpura; 3 with hemolytic uremic syndrome) with defibrotide, a new antithrombotic agent extracted from mammalian lungs. At admission all patients had severe renal involvement (serum creatinine 5.3-14.9 mg/dl) and coagulation abnormalities (low platelet count; high levels of circulating fibrin degradation products). There were neurological manifestations in 6 patients. Defibrotide administration was followed in 6 patients by recovery of renal function. In all patients, defibrotide therapy induced the disappearance of neurological manifestations and normalization of coagulation abnormalities. Defibrotide caused no side effects. All patients are alive after 7-22 months of follow-up.