What is the treatment for adult IgA (Immunoglobulin A) vasculitis?

Treatment of Adult IgA Vasculitis

For adult IgA vasculitis, treatment should be based on disease severity, with a combination of glucocorticoids and either cyclophosphamide or rituximab recommended for organ-threatening or life-threatening disease. 1

Disease Classification and Initial Assessment

Severity Assessment

• Severe disease: Life- or organ-threatening manifestations (e.g., glomerulonephritis, alveolar hemorrhage, central nervous system involvement, mononeuritis multiplex, cardiac involvement, mesenteric ischemia) 1
• Non-severe disease: Without life- or organ-threatening manifestations (e.g., cutaneous purpura, arthralgia/arthritis, mild gastrointestinal symptoms) 1

Key Diagnostic Elements

• Palpable purpura (typically on lower extremities)
• IgA deposition on immunofluorescence studies
• Renal involvement assessment (urinalysis, proteinuria, renal function)
• Gastrointestinal evaluation if symptoms present

Treatment Algorithm

1. Non-Severe Disease

• First-line: Supportive care and symptom management
  • NSAIDs for joint pain if renal function permits
  • Colchicine or dapsone may help control minor manifestations 2
  • Monitor for progression to more severe disease

2. Severe Disease with Organ Involvement

• First-line: Combination of glucocorticoids and immunosuppressive therapy 1
  • Glucocorticoids: Prednisone 1 mg/kg/day (generally up to 80 mg/day) 1
  • Plus one of the following:
    • Cyclophosphamide: 2 mg/kg/day oral (maximum 200 mg/day) OR
    • Cyclophosphamide IV pulse: 15 mg/kg IV every 2 weeks for 3 doses, then every 3 weeks 1
    • Rituximab: 375 mg/m² weekly for 4 doses OR 1,000 mg on days 1 and 15 1

3. Renal Involvement (IgA Vasculitis Nephritis)

• For proteinuria >1 g/day after optimized supportive care:

  • Consider glucocorticoid therapy (6-month course) if eGFR ≥30 mL/min/1.73m² 3
  • Add ACE inhibitor or ARB to achieve proteinuria <1 g/day 3
  • Target BP <125/75 mmHg for patients with proteinuria >1 g/day 3

• For rapidly progressive glomerulonephritis (>50% crescents):

  • Cyclophosphamide and high-dose corticosteroids 3
  • Consider plasma exchange for severe disease 1

4. Refractory Disease

• Switch from cyclophosphamide to rituximab or vice versa 1
• Consider mycophenolate mofetil as an alternative 4, 2
• Consult with vasculitis expert center for further management 1

Remission Maintenance

• Continue treatment for at least 24 months following induction of sustained remission 1
• Options include:
  • Azathioprine (up to 2 mg/kg/day)
  • Methotrexate (up to 25 mg/week)
  • Mycophenolate mofetil (up to 1,500 mg twice daily)
  • Rituximab (500 mg IV every 6 months or 1 g IV every 4 months) 1

Monitoring and Follow-up

• Regular urinalysis at each visit to screen for infection, renal relapse or response 1

• Periodic assessment (every 1-3 months) of:

  • Inflammatory markers
  • Renal function
  • Complete blood count
  • Liver function 1

• For patients on cyclophosphamide:

  • Monitor for leucopenia and adjust dosage as needed
  • Investigate persistent unexplained hematuria (risk of bladder cancer) 1
  • Consider MESNA for uroprotection 1

• For patients on rituximab:

  • Test serum immunoglobulin levels prior to each course and in patients with recurrent infection 1

Special Considerations

• Adult IgA vasculitis has a more severe course than pediatric cases, with higher risk of progression to end-stage renal disease 5, 6
• Cardiovascular risk assessment should be performed periodically 1
• Prophylaxis against Pneumocystis jirovecii with trimethoprim/sulfamethoxazole should be considered for patients on cyclophosphamide 1

Emerging Therapies

• SGLT2 inhibitors may be considered to reduce CKD progression 3, 6
• Other potential therapies with encouraging preliminary results include:
  • TRF-budesonide
  • Endothelin receptor antagonists
  • Complement pathway inhibitors 2, 6

Adult IgA vasculitis requires prompt recognition and appropriate treatment based on disease severity to improve outcomes and prevent long-term complications, particularly renal damage.