What are the initial and subsequent treatment options for Immune Thrombocytopenic Purpura (ITP) management?

ITP Diagnosis and Management

Initial corticosteroid treatment for 6-8 weeks is the recommended first-line therapy for adults with ITP who have platelet counts <30 × 10⁹/L, with second-line options including thrombopoietin receptor agonists, rituximab, or splenectomy for those who fail to respond. 1

Diagnosis of ITP

ITP is a diagnosis of exclusion that requires thorough evaluation:

• Essential diagnostic testing:

  • Complete blood count with peripheral blood smear review
  • Coagulation profile (PT, PTT, fibrinogen)
  • Liver and renal function tests
  • Testing for secondary causes:
    • HIV serology
    • Hepatitis B and C serology
    • H. pylori testing
  • Blood type and Rh(D) typing (if anti-D immunoglobulin treatment is considered) 1

• Important note: Bone marrow examination is not necessary in patients presenting with typical ITP 1

Treatment Algorithm

First-Line Treatment

1. Indications for treatment:

   • Platelet count <30 × 10⁹/L
   • Active bleeding regardless of platelet count
   • Treatment goal: platelet count >30-50×10⁹/L to prevent bleeding 1

2. First-line therapy options:

   • Corticosteroids (60-80% initial response rate, 20-40% sustained response)
     • Treatment duration should be limited to 6-8 weeks maximum
     • Longer courses preferred over shorter courses
     • Avoid excessively fast tapering to minimize adverse effects 1

Second-Line Treatment

Consider second-line therapy when:

• Patient requires on-demand administration of corticosteroids after completing first-line treatment
• Suboptimal response to continuous corticosteroid-based regimen
• Prolonged exposure to corticosteroids (risk of severe adverse events) 1

Second-line options:

1. Thrombopoietin receptor agonists (TPO-RAs):

   • Romiplostim or eltrombopag
   • Response rate: 50-60%
   • Consider for patients who have failed one line of therapy 1
   • Important safety considerations for romiplostim:
     • Risk of blood clots with high platelet counts
     • Weekly platelet count monitoring during dose adjustment phase
     • Monthly monitoring after establishing stable dose
     • Not for use in patients with myelodysplastic syndrome 2

2. Rituximab:

   • Consider for patients at risk of bleeding who have failed corticosteroids, IVIg, or splenectomy
   • Short-term response rate: 50-60%
   • Long-term response rate: 20-30% 1

3. Splenectomy:

   • Initial response rate: 85%
   • Durable responses: 60-65%
   • Recommended for patients who have failed corticosteroid therapy 1

4. Other immunosuppressive options:

   • Hydroxychloroquine (200-400 mg/day) - especially effective in patients with positive anti-Ro52 antibodies
   • Azathioprine, cyclosporine, or mycophenolate mofetil - to facilitate corticosteroid reduction 1

Emergency/Rapid Response Needed

For patients requiring rapid platelet count increase (significant bleeding or before procedures):

• Intravenous immunoglobulin (IVIg)
• Anti-D immunoglobulin (for Rh-positive, non-splenectomized patients) 1

Treatment Monitoring and Adjustment

• Weekly platelet count monitoring during dose adjustment phase
• Monthly monitoring after establishing stable dose
• 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 1

Special Considerations

Management of Secondary Causes

• Consider antiviral therapy in patients with ITP and hepatitis C infection
• Administer H. pylori eradication therapy if H. pylori infection is confirmed 1

Pregnancy

• Pregnant patients requiring treatment should receive either corticosteroids or IVIg
• Mode of delivery should be based on obstetric indications, not platelet count 1

Common Pitfalls to Avoid

1. Prolonged corticosteroid use - limit initial treatment to 6-8 weeks to minimize adverse effects
2. Treating based on platelet count alone rather than bleeding symptoms
3. Failure to screen for underlying conditions like HCV, HIV, and H. pylori
4. Unnecessary bone marrow examination in patients with typical ITP presentation
5. Rapid tapering of corticosteroids leading to relapse
6. Delaying follow-up - hematology follow-up recommended within 24-72 hours of discharge 1