HEMOLYTIC UREMIC SYNDROME POST-PARTUM: We describe a case of a 37-year-old woman admitted for severe renal failure to our hospital immediately after the delivery by caesarean section of twins. She had anuria, anemia, and moderate thrombocytopenia. A diagnosis of hemolytic-uremic syndrome was made. Plasma exchange was started, substitution was performed with fresh frozen plasma and eight consecutive plasmapheresis sessions were given. She received hydrocortisone and ACE inhibitors. After about fifteen days from the beginning of the illness, signs of active haemolysis disappeared and renal function was partially recovered. A genetic study demonstrated the absence of HF1 and MCP mutations but a polymorphic variant of the HF1 gene (C-257T promoter region). This polymorphism is strongly associated with non-diarrhoea-HUS (D-HUS). Post-partum HUS is quite a rare syndrome and has a poor outcome; however prompt diagnosis and efficacious therapy could save lives without clinical consequences. The excellent outcome of this patient seems to corroborate this concept.