In children, immune thrombocytopenic purpura (ITP) is usually an acute disease that may be secondary to a viral infection or immunization and that resolves spontaneously, whereas in adults the disease is usually chronic. Adult chronic ITP is a relatively common autoimmune disorder with 14,000 to 16,000 new cases occurring each year in the United States.1

The disease is caused by one or more antiplatelet autoantibodies that cause accelerated platelet destruction by the mononuclear phagocytic system (MPS), primarily in the spleen. Diagnosis is based on history, physical examination, complete blood count, and examination of the peripheral smear, which should exclude other causes of thrombocytopenia.2

Conventional treatment of ITP has included steroids, splenectomy, and IVIG3

  • Initial treatment with corticosteroids and splenectomy results in "safe" platelet counts of > 30,000/µL (30 x109/L) in more than 70% of patients.1
  • Among adults with chronic ITP receiving IVIG, platelet counts increase in about 75% of patients, but in most the platelet count returns to pretreatment levels within 3 to 4 weeks.2

TraQ self study question

1. By what mechanism do macrophages in the spleen remove antibody-coated cells?

Answer

More Discussion...

  • Part 1: Determining antibody specificity
  • Part 2: Immmune thrombocytopenic purpura (ITP) <--You are here
  • Part 3. Intravenous immune globulin (IVIG)
  • Part 4: Intravenous RhIG therapy in ITP
    • Part 4a: Passive antibodies (tools and resources)
    • Part 4b: Severe hemolysis (tools and resources)