Condition- Thrombotic Thrombocytic Purpura (TTP)

Question 1

What causes TTP?

Answer 1

Deficiency in ADAMTS13

Question 2

What is the function of the ADAMTS13 enzyme?

Answer 2

Breaks down vWF to prevent excessive accumulation on endothelium

Question 3

Describe the presentation of TTP. State the Mnemonic used to remeber it

Answer 3

ADAMTS13 (the enzyme)

• Antiglobulin -ve: -ve for Coombs (AIHA)
• Decreased platelets => bruising + bleeding
• AKI=> olig/anuria
• MAHA=> jaundice+anaemia
• Temperature
• Swinging CNS symptoms
  
  • Headaches, weakness, visual problems, confusion, seizures, coma

Question 4

Which gender is TTP more common in?

Answer 4

Females

Question 5

State the TTP pentad

Answer 5

The HUS triad:

• MAHA
• AKI
• Thrombocytopenia

+ 2 more:

• Fever
• CNS symptoms

Question 6

Which disease is TTP associated with?

Answer 6

HUS and MAHA

Question 7

What might you see in the bloods of someone with TTP?

Answer 7

• Signs of MAHA:
  
  • Low Hb + normal MCV
  • High reticulocytes
  • High bilirubin
  • low haptoglobins
  • High LDH (high turnover)
• Signs of AKI
  
  • High Cr, high Urea, also get high K+
• Signs of thrombocytopenia:
  
  • Low platelets

Question 8

What would you see on a blood film of someone with TTP?

Answer 8

schistocytes

spherocytes

Question 9

What would be the result of a DAT/Coomb’s test?

Answer 9

Negative

Means the haemolytic anaemia is not caused by AIHA