Haemolytic Uraemic Syndrome (HUS) + TTP

Question 1

What is Microangiopathic haemolytic anaemia

Answer 1

Shearing of RBCs dur to microthrombi formation (nets) and leads to schistocytes

Question 2

When does HUS present?

Answer 2

disease of early chidhood

Question 3

What is the triad for HUS?

Answer 3

1. Thrombocytopenia
2. AKI
3. MAHA: jaundice and conjunctival pallor

Question 4

What can HUS be caused by?

Answer 4

E coli

Question 5

What are some GI features of HUS?

Answer 5

abdominal pain and bloody diarrhoea

Question 6

What are general symptoms and signs of HUS?

Answer 6

1. Abdominal pain
2. Anaemia with leucocytosis
3. High serum bilirubin
4. Thrombocytopenia
5. AKI

Question 7

What does TTP stand for?

Answer 7

Thrombotic Thrombocytopenic Purpura

Question 8

What is the patho for TTP?

Answer 8

1. ADAMTS-13 enzyme is dysfunctional and so webs can’t be broken down
   2, Cleavage of the ADAMTS13 enzyme prevents build up of large oligomers (as shown on the right) which become microthrombi

Question 9

What are symptoms of TTP?

Answer 9

1. AKI
2. MAHA
3. Temperature
4. Swinging CNS signs
   (clinical pentad)

Question 10

What does Ix show for TTP?

Answer 10

1. Antiglobulin negative

2. Decreased platelets

Question 11

How do you tell the difference between HUS and TTP?

Answer 11

HUS has decreased platelets, AKI and MAHA but TTP has additionally temperature and swinging CNS signs

Question 12

What can plasmaphersis do?

Answer 12

removes antibodies against ADAMTS-13 and also replaces the enzyme

Question 13

What does DIC, HUS and TTP have in common?

Answer 13

DAT/Combs negative

Question 14

Is DAT and Coombs test the same?

Answer 14

yes

Question 15

What does the DAT test tell you?

Answer 15

if there is an auto-immune problem directly attacking the red blood cells

Question 16

What is the patho for dat test?

Answer 16

Detects the presence of antibody bound to the red cell surface e.g. autoimmune haemolytic anaemia