What is the workup for Immune Thrombocytopenic Purpura (ITP)?

From the Guidelines

The workup for Immune Thrombocytopenic Purpura (ITP) should include a history and physical examination, complete blood count (CBC), peripheral blood smear, reticulocyte count, and testing for HIV, HCV, HBV, and H. pylori, as recommended by the most recent guidelines 1. The initial evaluation of a patient with suspected ITP involves a thorough history and physical examination, with special attention to any history of viral illness, lymphocyte depleting therapy, or personal or family history of autoimmune disorders.

• Key components of the workup include:
  • CBC and peripheral blood smear to confirm thrombocytopenia and evaluate platelet morphology
  • Reticulocyte count to assess bone marrow function
  • Testing for HIV, HCV, HBV, and H. pylori to rule out underlying infections that may be contributing to the thrombocytopenia
  • Direct antigen test to rule out concurrent Evans’ syndrome
  • Nutritional evaluation to assess for any underlying nutritional deficiencies A bone marrow evaluation is typically reserved for patients with abnormalities in the initial testing results or when further investigation is necessary for a diagnosis, such as when other cell lines are affected or there is concern for aplastic anemia 1.
• Additional considerations in the workup include:
  • Avoiding medications that can affect platelet function, such as aspirin or NSAIDs
  • Initiating treatment with corticosteroids (e.g., prednisone 1 mg/kg/day) if severe thrombocytopenia (platelets <30,000/µL) is present, while completing the diagnostic evaluation 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Diagnosis of Immune Thrombocytopenic Purpura (ITP)

• The diagnosis of ITP requires excluding secondary causes of thrombocytopenia 2, 3, 4
• A complete blood count and a peripheral blood smear are the bare minimum workup for ITP in the emergency department 2
• The peripheral blood smear should show a small number of large platelets with normal morphology, and there should not be an increased number of schistocytes 2

Treatment of ITP

• The goal of treatment is to prevent severe or life-threatening bleeding 3, 4
• Corticosteroids are considered the standard initial treatment for newly diagnosed patients 3, 5
• Subsequent medical therapies with robust evidence include thrombopoietin receptor agonists (TPO-RAs), rituximab, and fostamatinib 3
• Surgical therapy with splenectomy may be considered for patients failing medical therapy 3, 4, 5
• Platelet transfusions are not recommended for less severe bleeding, but may be initiated in cases of critical hemorrhage, along with corticosteroids and intravenous immune globulin (IVIG) 2

Management Approach

• Treatment should be tailored according to the patient's age, lifestyle, comorbidities, and compliance 4
• The choice between therapy options is highly dependent upon patient values and preferences 3
• Recent updates on therapy guidelines recommend the shortest possible use of corticosteroids 5
• New drugs for ITP treatment are now available after steroid failure 5