Management of Vasculitis in IgA Nephropathy

Diagnostic Assessment and Immediate Action

The American College of Rheumatology suggests determining if the condition is drug-induced vasculitis versus IgA vasculitis, as the distinction fundamentally changes management, with drug-induced vasculitis requiring only medication withdrawal while IgAV may require immunosuppression 1, 2
The European Renal Association recommends obtaining ANCA testing immediately, as high-titre MPO ANCA positivity or dual MPO and PR3 ANCA positivity strongly suggests drug-induced rather than idiopathic vasculitis 2
The American Society of Nephrology advises assessing for life-threatening or organ-threatening manifestations, specifically evaluating for renal involvement, pulmonary involvement, or other major organ involvement 1
The British Society for Rheumatology suggests performing skin biopsy if cutaneous vasculitis is present, as leukocytoclastic vasculitis on biopsy supports drug-induced etiology 2

The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend discontinuing febuxostat immediately and observing without immunosuppression if limited cutaneous vasculitis is present without organ involvement, as drug withdrawal alone is often sufficient for drug-induced leukocytoclastic vasculitis 2
The European League Against Rheumatism (EULAR) suggests adding systemic corticosteroids only if signs of incipient skin necrosis develop, with a recommended dose of prednisolone 1 mg/kg/day (maximum 60 mg/day) 2
The American College of Rheumatology recommends initiating cyclophosphamide plus high-dose corticosteroids immediately if there is renal involvement, pulmonary involvement, or other organ-threatening manifestations, as this suggests true IgA vasculitis rather than drug-induced disease 1
The National Institute for Health and Care Excellence (NICE) advises administering intravenous methylprednisolone 500-1000 mg daily for 3 days, followed by oral prednisone 1 mg/kg/day 3

The American Heart Association recommends continuing enalapril (ACE inhibitor) as it provides essential RAS blockade, which should be maintained irrespective of hypertension if proteinuria >0.5 g/day 5, 6
The European Society of Cardiology suggests continuing dapagliflozin (SGLT2 inhibitor) as it reduces proteinuria and slows eGFR decline 5, 6
The American College of Rheumatology advises switching to allopurinol once vasculitis has resolved, starting at a low dose (≤100 mg daily, lower if CKD present) and titrating to target serum uric acid <6 mg/dL 1

The Centers for Disease Control and Prevention (CDC) recommends providing trimethoprim-sulfamethoxazole prophylaxis if immunosuppressive therapy is initiated, using 800/160 mg on alternate days or 400/80 mg daily for Pneumocystis jiroveci prevention 5, 6, 3
The CDC advises administering pneumococcal vaccine to patients with nephrotic syndrome and/or CKD 5, 6
The CDC recommends ensuring influenza vaccine for patient and household contacts 5, 6
The CDC suggests screening for tuberculosis, hepatitis B, hepatitis C, HIV, and syphilis before initiating immunosuppression 5, 6

The American Society of Nephrology recommends monitoring renal function, urinalysis, and inflammatory markers (CRP, ESR) weekly initially, then monthly until complete resolution 1
The National Kidney Foundation advises assessing for hematuria magnitude and persistence, as this has prognostic value in IgA nephropathy and IgA vasculitis 7
The European Renal Association suggests evaluating urine sediment for erythrocyte morphology, red cell casts, and acanthocytes routinely 7
The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend targeting proteinuria reduction to <1 g/day as a surrogate marker of improved kidney outcome 5, 6