Feature Article

Immune thrombocytopenia: a diagnosis of exclusion

Philip YI Choi, Scott Dunkley, John EJ Rasko



Immune thrombocytopenia (ITP) is best understood as an immune-mediated disorder of increased platelet destruction and impaired megakaryopoiesis. Most patients with ITP can be managed with careful monitoring alone or with traditional first- and second-line therapies with proven efficacy.

Key Points

  • Immune thrombocytopenia (ITP), previously known as idiopathic thrombocytopenic purpura, is not a single disease but instead encompasses a heterogenous group of disorders with a common manifestation.
  • ITP is due to both accelerated platelet destruction and insufficient platelet production.
  • The threshold for treatment in ITP is a platelet count of less than 30 x 109/L, or any evidence of bleeding with a platelet count of less than 50 x 109/L.
  • ITP in adults is most frequently chronic.
  • Thrombocytopenia in pregnancy has several causes (usually not immune) and careful planning may be required to manage it safely.