What is the initial treatment approach for patients with vasculitis?

Initial Treatment Approach for Vasculitis

For patients with vasculitis, the initial treatment should include high-dose glucocorticoids combined with either rituximab or cyclophosphamide depending on disease severity and organ involvement. 1

Disease Classification and Initial Assessment

Before initiating treatment, it's essential to:

• Determine the type of vasculitis (ANCA-associated, large vessel, medium vessel, or small vessel)
• Assess disease severity and organ involvement
• Rule out secondary causes (drug-induced, infection-associated, connective tissue disease-associated)

Initial Treatment Protocol

First-Line Therapy

1. Induction Therapy with Glucocorticoids:

   • IV methylprednisolone 500-1000 mg/day for 3-5 days 1
   • Followed by oral prednisone 1 mg/kg/day (maximum 60 mg/day) 1
   • Taper according to clinical response, aiming for ≤10 mg/day during remission

2. Combined Immunosuppressive Therapy based on disease severity:

   Disease Severity	Recommended Treatment
   Generalized/Severe	Rituximab + Glucocorticoids
   Non-Severe	Methotrexate + Glucocorticoids
   Refractory/Relapsing	Tocilizumab or Cyclophosphamide

Rituximab Protocol

• For ANCA-associated vasculitis (GPA/MPA): 375 mg/m² once weekly for 4 weeks 2
• Premedication with antihistamine and acetaminophen before each infusion to prevent infusion reactions 2

Cyclophosphamide Alternative

• Oral cyclophosphamide 2 mg/kg daily for 3-6 months may be used as an alternative to rituximab 2
• Monitor closely for adverse effects including bone marrow suppression, hemorrhagic cystitis, and infertility

Infection Prophylaxis

• Trimethoprim/sulfamethoxazole (800/160 mg on alternate days or 400/80 mg daily) for all patients on cyclophosphamide 1
• Essential for Pneumocystis jirovecii prophylaxis in immunosuppressed patients

Monitoring During Initial Treatment

• Regular assessment of:
  • Disease activity using validated tools (e.g., BVAS/GPA)
  • Complete blood count
  • Renal function
  • Electrolytes
  • Urinalysis
  • ANCA titers (if initially positive)

Special Considerations

• Fertility preservation: Counsel patients of childbearing age before starting cyclophosphamide 1
• Bone protection: All patients on glucocorticoids should receive osteoporosis prophylaxis 1
• Cardiovascular risk management: Aggressive management of hypertension and other cardiovascular risk factors 1
• Referral: Patients with ANCA-associated vasculitis should ideally be treated at centers with experience in vasculitis management 1

Treatment Response Assessment

• Complete remission is defined as absence of disease activity (BVAS/GPA of 0) while off glucocorticoid therapy 2
• If remission is achieved, transition to maintenance therapy
• If inadequate response after 3-6 months, consider alternative or additional immunosuppressive agents

Maintenance Therapy

After achieving remission, maintenance therapy options include:

• Azathioprine 1.5-2 mg/kg/day for 18-24 months 1
• Rituximab 500 mg IV every 6 months 1
• Methotrexate 20-25 mg/week (if creatinine <130 μmol/L) 1
• Low-dose glucocorticoids (5-7.5 mg/day) for 2 years, then gradual taper 1

The combination of high-dose glucocorticoids with appropriate immunosuppressive therapy has been shown to significantly improve outcomes in patients with vasculitis, with complete remission rates of 64% at 6 months with rituximab-based regimens 2.