ITP

Question 1

What is a trigger for ITP?

Answer 1

Viral infection

Question 2

What is a serious complication of ITP?

Answer 2

Upper GI bleeding, intracranial bleeding

Question 3

What are three treatments in the first line management of ITP?

Answer 3

IV immunoglobulins, platelet transfusions, steroids

Question 4

Which conditions are associated with ITP?

Answer 4

HIV, hep C, SLE, antiphospholipid syndrome

Question 5

What is the pathophysiology of ITP?

Answer 5

In patient with ITP, antibodies (most commonly IgG) are inappropriately produced targeted to glycoproteins on the surface of the platelets and megakaryocytes.

This causes them to be recognized by cells such as macrophages in the spleen and Kuppfer cells in the liver, with binding of the phagocytic Fcγ receptors to the antibodies resulting in subsequent endocytosis and phagocytic breakdown.

Additionally, this can result in T-cell mediated destruction of platelets. Antibodies to megakaryocytes inhibit their maturation and can further reduce platelet numbers.