Immune Thrombocytopenic Purpura

Question 1

Define ITP

Answer 1

Isolated thrombocytopenia (<100 x103/ul) secondary to autoimmune destruction of platelets

Question 2

What are the causes/risk factors of ITP?

Answer 2

Antiplatelet antibodies (anti-GPIIb-IIIa) -> rapid clearance of platelets in the spleen

Primary – idiopathic

Secondary
• HIV
• Hepatitis C
• H. pylori
• SLE
• Drug-induced

Question 3

What are the symptoms of ITP?

Answer 3

• Easy bruising
• Mucosal bleeding
• Menorrhagia
• Epistaxis

Question 4

What are the signs of ITP?

Answer 4

• Petechiae

* Bruises (purpura, ecchymoses)

Question 5

What investigations are carried out for ITP?

Answer 5

• FBC - reveals isolated thrombocytopenia without other abnormalities. If bleeding is excessive, there may be anaemia as well.
• Peripheral Blood Smear - distinguishes between true thrombocytopenia and pseudothrombocytopenia, which is due to EDTA in the collecting bottle.
• PT - normal
• APTT - normal
• TT - normal
• Serology - anti-platelet antibodies; may not be present.
• Exclude other causes: HIV, hepatitis C, and Helicobacter pylori tests are indicated.
- TFTs and pregnancy tests in women of childbearing age