Chronic idiopathic thrombocytopenia purpura - Clotting disorders

Chronic idiopathic thrombocytopenia purpura

Definition

Chronic idiopathic thrombocytopenia purpura (ITP) is a fall in platelet count thought to be of immune origin.

Age

Chronic ITP is seen predominantly in adults.

Sex

F > M

Aetiology/pathophysiology

Chronic ITP may occur with other autoimmune disorders such as systemic lupus erythematosus and thyroid disease. Platelet associated IgG antibodies are often detectable.

Clinical features

Patients present with easy bruising, purpura, epistaxis and menorrhagia.

Investigations

Full blood count and blood film identify the low platelet count, a bone marrow aspirate demonstrates normal or raised megakaryocytes.

Management

Prednisolone may produce a complete or partial remission. Intravenous immunoglobulin works by blocking the Fc receptors in the spleen. The effect is transient but is useful in severe bleeding and predicts the potential success of splenectomy. Other drugs used include azathioprine, vincristine and danzol. Platelet transfusions are only used in life threatening haemorrhage.