Idiopathic thrombocytopenic purpura (ITP)

Table of Contents

Definition

Idiopathic thrombocytopenic purpura is a bleeding disorder in which the immune system destroys platelets, which are necessary for normal blood clotting. Persons with the disease have too few platelets in the blood.

ITP is sometimes called immune thrombocytopenic purpura.


Alternative Names

Immune thrombocytopenic purpura; ITP


Causes, incidence, and risk factors

ITP occurs when certain immune system cells produce antibodies against platelets. Platelets help your blood clot by clumping together to plug small holes in damaged blood vessels.

The antibodies attach to the platelets. The spleen destroys the platelets that carry the antibodies.

In children, the disease sometimes follows a viral infection. In adults, it is more often a chronic (long-term) disease and can occur after a viral infection, with use of certain drugs, during pregnancy, or as part of an immune disorder.

ITP affects women more frequently than men, and is more common in children than adults. The disease affects boys and girls equally.



Review Date: 03/28/2010
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; James R. Mason, MD, Oncologist, Director, Blood and Marrow Transplantation Program and Stem Cell Processing Lab, Scripps Clinic, Torrey Pines, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)