S Chim

Abstract

Haemolytic uraemic syndrome is characterized by the triad of microangiopathic haemolytic anaemia, thrombocytopenia and acute renal failure. It is a common cause of acute renal failure in infants and young children. Diarrhoea-associated haemolytic uraemic syndrome is most commonly caused by E. coli 0157:H7. The epidemiology, pathophysiology and treatment options will be reviewed. Nondiarrhoea-associated haemolytic uraemic syndrome accounts for only 10% of all cases. It usually has a poorer outcome. Neuraminidase-producing Streptococcus pneumoniae is a common causative agent. The neuraminidase exposes the T (or Thomsen-Friedenreich) antigen in the cell membrane of erythrocytes, platelets and glomerular endothelial cells. Anti-T IgM in normal sera will react with the exposed T-antigen, resulting in agglutination and haemolysis of red blood cells, thrombocytopenia and thrombotic renal microangiopathy. The cautious use of blood and plasma products may improve the prognosis. Long-term follow up of the renal function is warranted in all patients with HUS as renal failure may develop more than 10 years after the initial insult.