Treatment for Immune Thrombocytopenic Purpura (ITP)
Corticosteroids are the recommended first-line treatment for adults with ITP, with longer courses preferred over shorter courses, followed by thrombopoietin receptor agonists or splenectomy for those who fail initial therapy. 1, 2
Initial Diagnosis and Evaluation
Before initiating treatment, essential diagnostic testing should include:
- Testing for HCV and HIV 2
- Complete blood count with peripheral blood smear review 1
- H. pylori testing 1
A bone marrow examination is not necessary in patients presenting with typical ITP 2.
Treatment Algorithm for Adults with ITP
First-Line Treatment
- Platelet count threshold for treatment: Treatment is recommended for adults with platelet counts <30 × 10⁹/L 2
- Preferred initial therapy:
- Corticosteroids (longer courses preferred over shorter courses) 2
- Prednisone 0.5-2 mg/kg/day for 2-4 weeks, followed by gradual tapering 1
- For severe cases requiring rapid platelet increase: Add IVIg 1 g/kg as a one-time dose (may be repeated if necessary) 2, 1
- If corticosteroids are contraindicated: IVIg or anti-D (in appropriate patients) 2
Second-Line Treatment (for those who fail corticosteroid therapy)
Thrombopoietin receptor agonists (e.g., romiplostim, eltrombopag) 2, 1
- Recommended for patients at risk of bleeding who relapse after splenectomy or have contraindications to splenectomy 2
- May also be considered for patients who have failed one line of therapy such as corticosteroids or IVIg without having splenectomy 2
- Romiplostim demonstrated significant efficacy in clinical trials with 61% of non-splenectomized patients and 38% of splenectomized patients achieving durable platelet responses compared to 5% and 0% with placebo, respectively 3
- Recommended for patients who have failed corticosteroid therapy 2
- Should be delayed for at least 12 months unless accompanied by severe disease unresponsive to other measures 2
- Both laparoscopic and open splenectomy offer similar efficacy 2
- Vaccination against encapsulated organisms required before procedure 1
Third-Line Treatment Options
- Immunosuppressants (azathioprine, cyclosporine, mycophenolate mofetil) 1
- Alternative agents: cyclophosphamide, danazol, dapsone 1
Special Considerations
Monitoring
- During dose adjustment phase: Monitor platelet count weekly 1
- After establishing stable dose: Monitor platelet count monthly 1
- Treatment goal: Platelet count >30-50×10⁹/L to prevent bleeding 1
- After splenectomy: No further treatment needed in asymptomatic patients with platelet counts >30 × 10⁹/L 2
Associated Conditions
- Hepatitis C: Consider antiviral therapy; use IVIg if ITP treatment required 1
- HIV: Start antiretroviral therapy first; consider corticosteroids, IVIg, or anti-D for ITP treatment 1
- H. pylori: Eradication therapy if infection confirmed 1
Pregnancy
- Pregnant patients requiring treatment should receive either corticosteroids or IVIg 2, 1
- Mode of delivery should be based on obstetric indications, not platelet count 1
Common Pitfalls and Caveats
Overtreatment: Treatment should be guided by bleeding symptoms rather than platelet count alone. Asymptomatic patients with platelet counts >30 × 10⁹/L after splenectomy should not receive further treatment 2.
Delayed splenectomy: While effective, splenectomy should be delayed for at least 12 months unless there is severe disease unresponsive to other measures 2.
Inadequate monitoring: Regular platelet count monitoring is essential during treatment, especially during dose adjustment phases 1.
Ignoring associated conditions: Always screen for and address underlying conditions like HCV, HIV, and H. pylori 2, 1.
Blood clot risk: Patients may have higher risk of blood clots if platelet count becomes too high during treatment with thrombopoietin receptor agonists like romiplostim 3.
By following this evidence-based approach, clinicians can effectively manage ITP while minimizing complications and improving patient outcomes.