What is the evaluation and treatment approach for vasculitis?

Evaluation and Treatment Approach for Vasculitis

The evaluation and treatment of vasculitis requires a structured clinical assessment, including disease activity measurement, damage assessment, and functional evaluation, with management decisions based on vasculitis type, severity, and organ involvement. 1

Diagnostic Evaluation

• ANCA testing (including indirect immunofluorescence and ELISA) should be performed when vasculitis is suspected, particularly for small and medium vessel vasculitis 1
• Biopsy of affected tissue is strongly recommended to confirm diagnosis, with histopathological evidence of vasculitis remaining the gold standard 1
• Comprehensive laboratory assessment should include:
  • Inflammatory markers (CRP, ESR) 1
  • Renal function tests 1
  • Urinalysis with microscopic examination and quantification of proteinuria 1
  • Serial ANCA measurements for monitoring disease activity 1
• Structured clinical assessment tools should be used at each visit:
  • Birmingham Vasculitis Activity Score (BVAS) 1
  • Disease Extent Index 1
  • Vasculitis Damage Index (VDI) 1, 2
  • Short Form 36 for functional assessment 1

Classification and Categorization

• Patients with ANCA-associated vasculitis (AAV) should be categorized according to disease severity to guide treatment decisions 1:
  • Non-organ threatening/non-life threatening
  • Generalized
  • Severe/organ threatening
  • Refractory disease
• Disease activity states should be clearly defined as 1:
  • Remission
  • Response
  • Refractory disease
  • Relapse

Treatment Approach

Induction Therapy for AAV

• For generalized organ or life-threatening AAV, a combination of cyclophosphamide (IV or oral) and glucocorticoids is recommended for remission induction 1
• For non-organ threatening or non-life threatening AAV, methotrexate (oral or parenteral) with glucocorticoids is recommended as a less toxic alternative to cyclophosphamide 1
• Rituximab with glucocorticoids is an effective alternative for remission induction in AAV 1, 3
• Plasma exchange is recommended for patients with rapidly progressive severe renal disease to improve renal survival 1
• High-dose glucocorticoids are an important component of remission induction therapy 1

Maintenance Therapy for AAV

• Remission-maintenance therapy should consist of low-dose glucocorticoids combined with either:
  • Azathioprine (strongest evidence) 1
  • Leflunomide 1
  • Methotrexate 1
  • Rituximab (for selected patients) 3

Treatment of Refractory Disease

• For progressive disease despite optimal therapy, consider:
  • Rituximab (particularly effective in refractory or relapsing AAV) 1, 3
  • Mycophenolate mofetil 1
  • 15-deoxyspergualin 1
  • Anti-thymocyte globulin 1
  • Infliximab 1, 4

Special Considerations

• For mixed essential cryoglobulinemic vasculitis (non-viral), immunosuppressive therapy is recommended 1
• For hepatitis C-associated cryoglobulinemic vasculitis, antiviral therapy is recommended 1
• For hepatitis B-associated polyarteritis nodosa, a combination of antiviral therapy, plasma exchange, and glucocorticoids is recommended 1

Monitoring and Follow-up

• Structured clinical assessment rather than ANCA testing should guide treatment decisions 1
• Regular monitoring should include:
  • Urinalysis at each visit to screen for infection, renal relapse, or bladder complications 1
  • Periodic assessment of inflammatory markers and renal function (every 1-3 months) 1
  • Full blood count and liver function tests to monitor for drug toxicity 1
  • Blood glucose assessment while on glucocorticoid therapy 1
• Serum immunoglobulin levels should be tested prior to each course of rituximab and in patients with recurrent infection 1, 3
• Patients with prior exposure to cyclophosphamide require investigation of persistent unexplained hematuria due to increased risk of bladder cancer 1
• Periodic assessment of cardiovascular risk is recommended 1

Common Pitfalls and Caveats

• Failing to use standardized assessment tools can lead to inconsistent evaluation of disease activity and damage 1, 2
• Relying solely on ANCA titers to guide treatment decisions is not recommended; clinical assessment is more important 1
• Inadequate immunosuppression during induction therapy may result in poor disease control and organ damage 1
• Excessive immunosuppression increases risk of infection, which is a major cause of morbidity and mortality 3
• Patients with AAV are at increased risk for cardiovascular disease beyond traditional risk factors 1
• Long-term complications of therapy (particularly cyclophosphamide) include malignancy, especially bladder cancer 1
• Hypoimmunoglobulinemia can occur after treatment with rituximab or repeated cyclophosphamide, increasing infection risk 3

Referral Considerations

• Patients with vasculitis should be managed in collaboration with, or at centers of expertise 1
• Patients with refractory disease should be referred to expert centers for further management and potential enrollment in clinical trials 1