Is skin bleeding with painful reddish marks over both legs in a patient with Lupus and ANCA (Antineutrophil Cytoplasmic Antibodies) vasculitis overlap, on Wysolone (Prednisone) 5 mg and MMF (Mycophenolate Mofetil) 500 mg twice daily, a manifestation of vasculitis or a side effect of steroids after increasing Prednisone to 30 mg od?

Urgent Skin Biopsy Required: This is Active Vasculitis Until Proven Otherwise

Your patient's painful reddish marks with bleeding over both legs, worsening after increasing prednisone to 30 mg, most likely represent active cutaneous vasculitis requiring immediate deep skin biopsy and aggressive immunosuppression escalation. The development of pain after steroid increase strongly argues against steroid-induced purpura and points toward inadequately controlled vasculitis 1.

Critical Diagnostic Step: Deep Skin Biopsy NOW

• Obtain a deep skin biopsy extending to the subcutis from the most tender, reddish or purpuric lesion immediately 1
• Request serial sections to identify the main vasculitic lesion 1
• Order direct immunofluorescence to distinguish IgA-associated vasculitis from IgG-/IgM-associated vasculitis, which has prognostic significance 1
• The biopsy should reach medium-sized vessels of the dermis, as superficial punch biopsies miss vasculitis in ANCA-associated disease 2

Why This is Active Vasculitis, Not Steroid Side Effects

Steroid-induced purpura does NOT become painful and does NOT worsen acutely after dose escalation 3. Key distinguishing features:

• Steroid purpura: Painless, spontaneous hemorrhage with skin tearing, associated with chronic high-dose steroids (typically years of use), accompanied by other cushingoid features (moon facies, skin thinning, extensive purpura on extremities) 3
• Your patient: Painful lesions that developed on only 5 mg prednisone (far below the threshold for steroid purpura), worsening with appropriate vasculitis treatment dose escalation 3
• The pain development after increasing to 30 mg prednisone indicates the lesions are inflammatory (vasculitic) rather than atrophic (steroid-induced) 1

Your Current Treatment is Inadequate

MMF 500 mg twice daily (1000 mg total) is a subtherapeutic dose for active ANCA vasculitis 2. The evidence shows:

• Standard MMF dosing for ANCA vasculitis is up to 1500 mg twice daily (3000 mg total) 2
• Your patient is receiving only one-third of the recommended dose 2
• This explains why she developed active vasculitis despite being on "maintenance" therapy 4

Immediate Management Algorithm

Step 1: Confirm Active Disease (Within 24-48 Hours)

• Deep skin biopsy with direct immunofluorescence 1
• Check ANCA titers (MPO and PR3 by antigen-specific immunoassay) 5
• Assess for systemic involvement: urinalysis with microscopy for RBC casts, serum creatinine, chest imaging if any respiratory symptoms 5, 6

Step 2: Escalate Immunosuppression Immediately (Don't Wait for Biopsy)

For severe cutaneous vasculitis with pain (indicating tissue ischemia), treat as severe disease 2:

• Continue prednisone 30 mg daily (this is moderate-dose for a 37-year-old, approximately 0.5 mg/kg) 2
• Increase MMF to 1500 mg twice daily (3000 mg total) 2
• Consider IV pulse methylprednisolone 500-1000 mg daily for 3-5 days if lesions are rapidly progressive or ulcerating 2

Step 3: If No Response in 2-4 Weeks, This is Refractory Disease

Refractory vasculitis requires rituximab or cyclophosphamide 5:

• Add rituximab 375 mg/m² IV weekly for 4 doses OR 1000 mg on days 1 and 15 2
• Alternative: cyclophosphamide if rituximab unavailable 2
• Consider plasma exchange for severe refractory cutaneous vasculitis 5

Critical Pitfall: Coexistence of Pan-Dermal and Subcutaneous Vasculitis

If biopsy shows both small-vessel and muscular-vessel vasculitis, this indicates more aggressive systemic disease 1:

• This pattern suggests ANCA-associated vasculitis with high relapse risk 1
• Requires more aggressive induction therapy (rituximab preferred over MMF) 2, 5
• Mandates thorough systemic evaluation for renal, pulmonary, and neurologic involvement 6

Long-Term Maintenance After Remission

Once remission is achieved, proper maintenance dosing is critical 2:

• MMF 2000 mg daily (divided doses) for 2 years minimum 2
• Prednisone 5-7.5 mg daily for 2 years, then taper by 1 mg every 2 months 2, 5
• Your patient was likely under-immunosuppressed during "remission," predisposing to this relapse 4

Bottom Line

Stop thinking of this as a steroid side effect—5 mg prednisone does not cause painful bleeding skin lesions 3. Your patient has active vasculitis that was inadequately suppressed by subtherapeutic MMF dosing 4. Get the deep skin biopsy today, increase MMF to 3000 mg daily, and prepare to add rituximab if she doesn't respond within 2-4 weeks 2, 5, 1.