Definition

Immune thrombocytopenia purpura (ITP) is a bleeding disorder. It is a drop in the number of platelets in your blood. Platelets are small cells that stick together to form blood clots. These clots help stop bleeding at injury sites. ITP causes bruising or bleeding even with minor injuries.

There are 2 types:

• Primary—no known cause
• Secondary—caused by an underlying condition or medicines

Causes

Problems with the immune system cause ITP. The body attacks healthy tissue. In this case, platelet cells are removed from the bloodstream. They are destroyed by the spleen and liver. Over time, there is a drop in healthy cells. The drop can be severe enough to cause problems with blood’s ability to clot.

For most ITP, it is not clear what causes these problems. In children, ITP is often related to a recent viral infection. ITP in adults has not been linked to viruses.

Sometimes, certain medicines cause ITP or other problems with the immune system.

Risk Factors

The chances of ITP are higher for:

• Women—mainly those under 40 years old
• Children—history of a viral infection or vaccine with a live virus

Symptoms

ITP may cause:

• Easy bruising
• Blood in the urine or stool
• Bleeding for longer than normal
• Unexplained nosebleeds
• Bleeding from the gums
• In adult women, heavier bleeding during a period
• Red dots on the skin—may happen in groups and look like a rash
• Bleeding within the intestines or brain—rare

Diagnosis

The doctor will ask about your symptoms and health history. You may have:

• A physical exam
• Blood tests
• Bone marrow tests

Treatment

Care for ITP is different for children and adults. ITP is short term in most children. Most children will improve on their own. Adults are more likely to have a long lasting form of ITP. Not all forms need care.

Care may involve:

Prevention

There is no way to prevent ITP since the cause is unknown.