<prompt> A 8-year-old boy presents with petechiae, azotemic oliguria and altered sensorium, in casualty. There is a history of diarrhoea for the past 5 days. The clinical diagnosis isAcute prophyriaIdiopathic thrombocytopenic purpuraH.S. purpuraH.U.S.  <response>: Hemolytic uremic syndrome HUS is characterized by the triad of -Anaemia microangiopathic hemolytic anaemiaRenal failure microangiopathy of kidney involving glomerular capillaries and arterioles.Thrombocytopenia due to platelet destructionHUS is common in children under 2 years of age. But may also occur in older children.It usually follows an episode of acute gastroenteritis.The prodrome is usually of abdominal pain, diarrhoea and vomiting.Shortly thereafter, signs and symptoms of acute hemolytic anaemia, thrombocytopenia and acute renal failure ensue.Sometimes neurological findings also occur But usually absent and differentiates HUS from TTP. 