What are the initial labs and treatment for Immune Thrombocytopenic Purpura (ITP)?

Initial Labs and Treatment for Immune Thrombocytopenic Purpura (ITP)

The initial diagnostic workup for ITP requires a complete blood count with peripheral blood smear examination, and first-line treatment includes corticosteroids or IVIG for patients with significant bleeding or platelet counts below 20,000/μL. 1

Diagnostic Workup

Essential Initial Labs

• Complete blood count (CBC) with platelet count is the fundamental first test for suspected ITP 1, 2
• Peripheral blood smear examination to confirm thrombocytopenia and exclude other causes 3, 1, 2
  • Normal-sized or slightly larger platelets
  • Normal red blood cell morphology
  • Normal white blood cell morphology
  • Absence of schistocytes, poikilocytosis, or abnormal white blood cells

Additional Testing

• HIV and HCV testing is strongly recommended for all patients with suspected ITP (grade 1B) 1, 2
• Screening for H. pylori should be considered in patients where eradication therapy would be used if positive (grade 2C) 1
• Bone marrow examination is NOT necessary in patients presenting with typical ITP features (grade 1B) 3, 1
• Further investigations only if abnormalities other than thrombocytopenia are present in the blood count or smear 1

Treatment Approach

Indications for Treatment

• Treatment is indicated for patients with platelet counts <10,000/μL regardless of bleeding symptoms 1, 4
• Treatment is indicated for patients with platelet counts <20,000/μL with significant mucous membrane bleeding 1, 4
• Patients with platelet counts >30,000/μL and minimal symptoms generally do not require specific treatment 2

First-Line Treatment Options

• Corticosteroids (oral prednisone or high-dose dexamethasone) 3, 1
• Intravenous Immunoglobulin (IVIG) at an initial dose of 1 g/kg as a one-time dose; may be repeated if necessary (grade 2B) 3, 1
• IVIG should be used with corticosteroids when a more rapid increase in platelet count is required (grade 2B) 1
• Anti-D immunoglobulin can be used as first-line treatment in Rh-positive, non-splenectomized patients if corticosteroids are contraindicated (grade 2C) 3, 1

Management of Severe or Life-Threatening Bleeding

• High-dose parenteral glucocorticoid therapy 1, 5
• IVIG administration 1, 5
• Platelet transfusions 1, 5
• Hospitalization for patients with platelet counts <20,000/μL who have significant mucous membrane bleeding 1

Special Considerations

Secondary ITP Management

• For HCV-associated ITP: Consider antiviral therapy; if ITP treatment is required, use IVIG initially (grade 2C) 3, 1
• For HIV-associated ITP: Consider antiviral therapy first unless significant bleeding is present (grade 1A); if ITP treatment is needed, use corticosteroids, IVIG, or anti-D (grade 2C) 3, 1
• For H. pylori-associated ITP: Administer eradication therapy if H. pylori infection is confirmed (grade 1B) 3, 1

Pregnancy

• Pregnant women with ITP and platelet counts >50,000/μL do not routinely require treatment 1
• Pregnant patients requiring treatment should receive either corticosteroids or IVIG (grade 1C) 3, 1
• Mode of delivery should be based on obstetric indications rather than platelet count (grade 2C) 3, 1

Second-Line Treatment Options

• Thrombopoietin receptor agonists for patients who have failed first-line therapy (grade 2C) 3, 1, 6
• Rituximab for patients who have failed first-line therapy (grade 2C) 3, 1
• Splenectomy for patients who fail initial corticosteroid therapy (grade 1B) 3, 1