HUS

• Haemolytic uraemic syndrome (HUS) involves thrombosis in small blood vessels throughout the body, usually triggered by Shiga toxins from either E. coli O157 or Shigella. 
• It most often affects children following an episode of gastroenteritis

  Antibiotics and anti-diarrhoeal medication used to treat gastroenteritis increase the risk of HUS
• HUS leads to the classic triad of:

  • Microangiopathic haemolytic anaemia (intrinsic haemolysis)
  • Acute kidney injury
  • Thrombocytopenia
• Pathophysiology:

  • Microangiopathic haemolytic anaemia - destruction of red blood cells due to pathology in the small vessels
  • Thrombi partially obstruct the small blood vessels and cause RBCs to rupture as they pass through
  • Formation of clots consumes platelets - thrombocytopenia
  • Blood flow through the kidneys is affected by thrombi - acute kidney injury
• Symptoms:

  • Diarrhoea is the first symptom which turns bloody within 3 days. Symptoms of HUS occur after around a week
  • Fever
  • Abdominal pain
  • Lethargy
  • Pallor
  • Oliguria
  • Haematuria
  • Hypertension
  • Bruising
  • Jaundice
  • Confusion
• HUS is a medical emergency that requires hospital treatment for:

  • Hypovolaemia - IV fluids
  • Hypertension
  • Severe anaemia - blood transfusions
  • Severe renal failure - haemodialysis
• It is self-limiting, and most patients fully recover with good supportive care.