[Recurrent atypical hemolytic uremic syndrome after renal transplantation: treatment with eculizumab].

Atypical hemolytic uremic syndrome (aHUS) is a rare entity. It is characterized by a thrombotic microangiopathy (nonimmune hemolytic anemia, thrombocytopenia, and acute renal failure), with a typical histopathology of thickening of capillary and arteriolar walls and an obstructive thrombosis of the vascular lumen. The syndrome is produced by a genetic or acquired deregulation of the alternative pathway of the complement system, with high rates of end stage renal disease, post-transplant recurrence, and high mortality. Mutations associated with factor H, factor B and complement C3 show the worst prognosis. Even though plasma therapy is occasionally useful, eculizumab is effective both for treatment and prevention of post-transplant recurrence. We describe here an adult case of congenital aHUS (C3 mutation) under preventive treatment with eculizumab after renal transplantation, with neither disease recurrence nor drug-related adverse events after a 36-months follow-up.