Immune thrombocytopenia (formerly idiopathic thrombocytopenic purpura [ITP]) occurs because of platelet injury and destruction. Pinpoint, red, nonblanching petechiae or nonpalpable purpura and ecchymoses are found on the skin and mucous membranes, either spontaneously (platelets < 10,000/mm3) or at the site of minimal trauma (platelets < 40,000/mm3). Petechiae are commonly found on dependent areas. Gingival bleeding, melena, hematochezia, menorrhagia, and severe intracranial hemorrhages may also occur. The newly diagnosed form affects children (peak incidence in 2- to 4-year-olds, equal gender distribution) after a viral illness or vaccination and completely resolves in 3 months. The chronic form occurs most often in adults, with women outnumbering men and a prolonged course of thrombocytopenia.
Management and Disposition
Consult hematology for medical management guidance. Treatment can include observation, oral or systemic corticosteroids, IVIG, rituximab, thrombopoietin receptor agonists, and platelet transfusions alone or in combination.
Isolated thrombocytopenia is the hallmark finding; white blood cell, hemoglobin, and coagulation levels should be normal (if no major hemorrhage).
Patients with advanced age, comorbidities, and prior history of hemorrhage have a high risk of associated bleeding (eg, central nervous system). In addition, adults have a higher incidence of thromboembolism. Keep a low threshold for working up these patients and insist on appropriate disposition.
The newly diagnosed form of immune thrombocytopenia (symptoms < 3 months in duration) has an excellent prognosis, whereas chronic immune thrombocytopenia (symptoms > 12 months in duration) has varying severity.
Immune Thrombocytopenia. This thrombocytopenic patient with splenomegaly has pinpoint, nonblanching, nonpalpable petechiae. (Photo contributor: R. Jason Thurman, MD.)
Immune Thrombocytopenia. Nonpalpable purpura. (Photo contributor: Lawrence B. Stack, MD.)