Treatment of ANCA-Associated Vasculitis

Initial Management and Induction Therapy

The American College of Rheumatology recommends that all patients with ANCA-associated vasculitis should be managed at centers with expertise in vasculitis treatment to ensure optimal outcomes and access to specialized care 2, 3
The European Renal Association suggests that in patients with clinical presentation compatible with small-vessel vasculitis and positive MPO- or PR3-ANCA serology, immunosuppressive therapy should not be delayed while waiting for kidney biopsy results, especially in rapidly deteriorating patients 4
The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines state that tissue biopsy should be obtained when feasible to confirm diagnosis, as histopathological evidence of pauci-immune glomerulonephritis or necrotizing vasculitis remains the gold standard 2, 3

The American College of Cardiology recommends glucocorticoids combined with either rituximab or cyclophosphamide as initial treatment for new-onset ANCA-associated vasculitis 1, 5, 4
The European League Against Rheumatism (EULAR) suggests that rituximab is preferred over cyclophosphamide for PR3-ANCA positive patients and those with relapsing disease, as post-hoc analysis showed superior remission rates 5
The National Institute for Health and Care Excellence (NICE) recommends that rituximab maintenance after cyclophosphamide induction is superior to azathioprine for preventing relapses 1

The American Thoracic Society recommends considering plasma exchange for patients with serum creatinine ≥500 μmol/L (5.7 mg/dL) due to rapidly progressive glomerulonephritis 2, 3, 8
The Infectious Diseases Society of America suggests that all patients receiving cyclophosphamide must receive Pneumocystis jirovecii pneumonia prophylaxis with trimethoprim/sulfamethoxazole 2, 3, 8, 7
The European Renal Association recommends regular monitoring of kidney function, urinalysis with proteinuria quantification, inflammatory markers, and ANCA levels 5, 4

The American College of Rheumatology recommends treating major relapse (organ-threatening or life-threatening) with glucocorticoids combined with either cyclophosphamide or rituximab 2, 3, 8
The European League Against Rheumatism (EULAR) suggests that rituximab is preferred for relapsing disease based on superior response rates in patients with prior relapses 5
The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines state that periodic assessment of cardiovascular risk is essential, as mortality remains 2.6-fold higher than the general population 2, 6, 3