Thrombotic thrombocytopenic purpura

Question 1

What is TTP?

Answer 1

Small emboli that develop throughout the small vessels, using up platelets

Question 2

What is the pathophysiology of TTP?

Answer 2

Congenital deficiency or autoimmune attack of ADAMTS13 protease leading to platelet aggregation and activation of clotting

Microemboli formation leads to platelet consumption and haemolytic anaemia

Question 3

What are the causes of TTP?

Answer 3

Post-infection
Pregnancy
Drugs
- Ciclosporin
- COCP
- Penicillin
- Clopidogrel
- Aciclovir
Tumours
SLE
HIV

Question 4

What is the pentad of features in TTP?

Answer 4

Thrombocytopenic purpura
Microangiopathic haemolytic anaemia
Neurological dysfunction
Renal dysfunction
Fever

Question 5

What is the presentation of TTP?

Answer 5

Confusion
Seizures
Headache
Bleeding
Chest pain
Abdominal pain
Jaundice

Question 6

What is the diagnostic investigation for TTP?

Answer 6

ADAMTS13 activity - will be low

Question 7

What investigations are useful in the diagnosis of TTP?

Answer 7

Urine dipstick - haematuria and proteinuria
FBC - normocytic anaemia
Clotting is typically normal
Blood film - schistocytes
LDH - raised in haemolysis
U&Es - raised creatinine (AKI)

Question 8

What is the management of TTP?

Answer 8

FFP - fresh frozen plasma (containing vWF-cleaving protease and complement components)
Plasma exchange
Corticosteroids - prednisolone or methylprednisolone