Idiopathic thrombocytopenic purpura (ITP) is a bleeding disorder in which the immune system destroys platelets, which are necessary for normal blood clotting. People with the disease have too few platelets in the blood.
ITP is sometimes called immune thrombocytopenic purpura or simply, immune thrombocytopenia.
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 body destroys the platelets that carry the antibodies.
In children, the disease sometimes follows a viral infection. In adults, it is more often a long-term (chronic) 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 often than men. It is more common in children than adults. In children, the disease affects boys and girls equally.
ITP symptoms can include any of the following:
- Abnormally heavy periods in women
- Bleeding into the skin, often around the shins, causing a skin rash that looks like pinpoint red spots (petechial rash)
- Easy bruising
- Nosebleed or bleeding in the mouth
In children, the disease usually goes away without treatment. Some children may need treatment.
Adults are usually started on a steroid medicine called prednisone. In some cases, surgery to remove the spleen (splenectomy) is recommended. This increases the platelet count in about half of people. However, other drug treatments are usually recommended instead.
If the disease does not get better with prednisone, other treatments may include:
- Medicine called danazol (Danocrine) taken by mouth
- Infusions of high-dose gamma globulin (an immune factor)
- Drugs that suppress the immune system
- Anti-RhD therapy for people with certain blood types
- Drugs that stimulate the bone marrow to make more platelets
People with ITP should not take aspirin, ibuprofen, or warfarin, because these drugs interfere with platelet function or blood clotting, and bleeding may occur.
With treatment, the chance of remission (a symptom-free period) is good. In rare cases, ITP may become a long-term condition in adults and reappear, even after a symptom-free period.
Sudden and severe loss of blood from the digestive tract may occur. Bleeding into the brain may also occur.
When to Contact a Medical Professional
Go to the emergency room or call the local emergency number (such as 911) if severe bleeding occurs, or if other new symptoms develop.
Immune thrombocytopenic purpura; ITP; Immune thrombocytopenia; Bleeding disorder - idiopathic thrombocytopenic purpura; Bleeding disorder - ITP; Autoimmune - ITP; Low platelet count - ITP
Abrams CS. Thrombocytopenia. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 172.
Arnold DM, Patriquin C, Toltl LJ, Nazi I, Smith J, Kelton J. Diseases of platelet number: immune thrombocytopenia, neonatal alloimmune thrombocytopenia, and posttransfusion purpura. In: Hoffman R, Benz EJ, Silberstein LE, Heslop HE, Weitz JI, Anastasi J, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 133.
Update Date 2/1/2016
Updated by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.