Vasculitis Relapse in Lupus-ANCA Overlap

Clinical Presentation

• Skin is a commonly involved organ system in ANCA-associated vasculitis, presenting as palpable purpura or infiltrated erythema indicating dermal small-vessel vasculitis, according to the Kidney International guidelines 1, 2

Maintenance Therapy

• The KDIGO 2024 guidelines recommend MMF 2000 mg/day in divided doses for AAV maintenance therapy, and subtherapeutic dosing substantially increases relapse risk 3, 4
• 5 mg prednisolone is within the recommended maintenance dose range for AAV in remission, as stated by the Kidney International guidelines 3, 5, 4, 6

Diagnostic Workup

• ANCA titers (MPO and PR3) should be assessed to evaluate serologic activity, and urinalysis with microscopy should be performed to look for signs of renal relapse, according to the Kidney International guidelines 1, 2, 6
• Serum creatinine and inflammatory markers (CRP, ESR) should be evaluated to assess systemic activity 1, 2

Management

• If vasculitis is confirmed, increase glucocorticoids (oral or intravenous) for acute relapse, and consider reinduction therapy with rituximab, as recommended by the Kidney International guidelines 3, 4, 6
• Optimize MMF dosing to 2000 mg/day if continuing as maintenance agent, to minimize relapse risk 3, 4

Critical Considerations

• Do not wait for biopsy results if clinical presentation strongly suggests vasculitis with systemic features - start treatment immediately, as advised by the Kidney International guidelines 1, 2
• Subtherapeutic immunosuppression is a major relapse risk factor, and should be avoided 3, 4

Vasculitis Relapse Assessment and Management

Diagnostic Considerations

• Palpable purpura is the most vasculitis-specific skin lesion in ANCA-associated vasculitis, and painful skin lesions strongly suggest active small-vessel vasculitis rather than steroid-induced ecchymoses, according to Nature Reviews Rheumatology 7
• The presence of painful skin lesions warrants aggressive evaluation for systemic involvement, as stated in Nature Reviews Rheumatology 7

Treatment Approach

• The KDIGO guidelines recommend glucocorticoid tapering gradually after clinical improvement, as mentioned in Kidney International 8
• Consider reinduction therapy with rituximab if vasculitis is confirmed on workup or clinical presentation worsens, as suggested in Kidney International 8