Renal Medicine

Question 1

What is it?

Answer 1

Haemolytic uraemic syndrome (HUS) occurs when there is thrombosis in small blood vessels throughout the body. This is usually triggered by a bacterial toxin called the shiga toxin. It leads to the classic triad of:

Haemolytic anaemia
Acute kidney injury
Low platelet count (thrombocytopenia)

The formation of blood clots consumes platelets, leading to thrombocytopenia. The blood clots within the small vessels chop up the red blood cells as they pass by (haemolysis), causing anaemia. The blood flow through the kidney is affected by the clots and damaged red blood cells, leading to acute kidney injury.

Question 2

Presentation

Answer 2

E. coli 0157 causes a brief gastroenteritis often with bloody diarrhoea.

Around 5 days after the diarrhoea the person will start displaying symptoms of HUS:

Reduced urine output
Haematuria or dark brown urine
Abdominal pain
Lethargy and irritability
Confusion
Hypertension
Bruising

Question 3

Management

Answer 3

HUS is a medical emergency and has up to 10% mortality. The condition is self limiting and supportive management is the mainstay of treatment:

Antihypertensives
Blood transfusions
Dialysis