How should I diagnose and treat Henoch‑Schönlein purpura (IgA vasculitis)?

Diagnosis and Treatment of Henoch-Schönlein Purpura (IgA Vasculitis)

Diagnosis

Diagnose IgA vasculitis clinically based on palpable purpura plus at least one of: diffuse abdominal pain, arthritis/arthralgia, renal involvement (hematuria/proteinuria), or biopsy showing predominant IgA deposition. 1

Clinical Presentation to Recognize

• Palpable purpura (non-thrombocytopenic) is the hallmark finding and must be present 1, 2
• Arthritis or arthralgia affecting large joints, particularly lower extremities 1
• Abdominal pain with or without gastrointestinal bleeding 1, 2
• Renal involvement manifesting as hematuria and/or proteinuria 1, 3
• The classic triad of purpura, arthralgia, and abdominal pain should raise immediate suspicion 4

Essential Diagnostic Workup

Baseline investigations for every suspected case:

• Blood pressure measurement to detect hypertension 5
• Urinalysis to identify hematuria and proteinuria 1, 5
• Estimated glomerular filtration rate (eGFR) 5
• Complete blood count to confirm non-thrombocytopenic purpura 2
• Serum creatinine 1

Skin biopsy when diagnosis is uncertain: Leukocytoclastic vasculitis with predominant IgA deposition in vessel walls is diagnostic 1, 2

Renal biopsy indications: 1

• Persistent proteinuria >1 g/day
• Declining renal function
• Nephrotic-range proteinuria
• To determine severity and guide treatment in moderate-to-severe nephritis

Important Diagnostic Caveats

• No formal diagnostic criteria exist—classification criteria (2012 EULAR/PRINTO/PRES Ankara criteria or 2022 ACR-EULAR criteria) should NOT be used for diagnosis 1
• IgA vasculitis is primarily a clinical diagnosis; biopsy is recommended when feasible but not essential 1
• Exclude other causes of purpura through appropriate testing 2

---

Treatment

Non-Renal Disease (Skin, Joints, Mild GI Symptoms)

Supportive care is the primary management strategy, as 94% of children and 89% of adults experience spontaneous resolution. 2

• Adequate analgesia for joint and abdominal pain 1
• NSAIDs for arthritis/arthralgia (use cautiously if renal involvement present) 1
• Avoid prophylactic corticosteroids—systematic reviews show they do not prevent complications 2, 3

Corticosteroids for severe gastrointestinal manifestations: 1, 3

• Oral prednisone 1-2 mg/kg/day (maximum 60-80 mg/day) for severe abdominal pain or GI hemorrhage
• Duration: 1-2 weeks with rapid taper
• Evidence does NOT support routine steroid use for uncomplicated disease 2, 3

Renal Disease (IgA Vasculitis Nephritis)

Treatment intensity depends on severity of nephritis:

Mild Nephritis (Isolated hematuria or proteinuria <1 g/day)

• ACE inhibitors or ARBs as first-line therapy to prevent secondary glomerular injury 1, 3
• Oral corticosteroids (prednisone 1-2 mg/kg/day) if proteinuria persists >3 months 1, 3

Moderate Nephritis (Proteinuria 1-3 g/day or crescents on biopsy <50%)

• Pulsed intravenous methylprednisolone (15-30 mg/kg/day for 3 days, maximum 1 g/day) 1, 5
• Followed by oral prednisone 1-2 mg/kg/day with gradual taper over 3-6 months 1
• Add ACE inhibitor/ARB for renoprotection 1, 3

Severe Nephritis (Rapidly progressive GN, crescents >50%, nephrotic syndrome, declining GFR)

• Pulsed IV methylprednisolone (as above) PLUS 1, 5
• Cyclophosphamide (intravenous pulses 500-750 mg/m² monthly for 6 months) 1, 6, 5
• Alternative to cyclophosphamide: Mycophenolate mofetil (600 mg/m² twice daily) has shown favorable results as glucocorticoid-sparing agent 6
• ACE inhibitor/ARB for long-term renoprotection 1, 3

Refractory or Relapsing Disease

For patients not responding to standard therapy: 6

• Rituximab has demonstrated efficacy in reducing relapse frequency and achieving long-term remission in both children and adults 6
• Cyclosporine A or tacrolimus as glucocorticoid-sparing agents 6
• Plasma exchange for life-threatening situations 6
• Intravenous immunoglobulin for difficult cases 6

---

Follow-Up and Monitoring

Six months of follow-up is mandatory to assess for disease relapse or remission, even in mild cases 2

Long-term monitoring for patients with renal involvement: 3, 5

• Blood pressure checks at every visit
• Urinalysis and urine protein quantification
• Serum creatinine and eGFR
• Renal involvement can persist and relapse years later 2

Prognosis

• Most cases are self-limited with excellent outcome 3
• Renal involvement is the most important prognostic factor determining long-term morbidity and mortality 3
• 10-30% of adults with IgA vasculitis nephritis progress to end-stage renal disease 6
• Early steroid treatment does NOT reduce incidence or severity of nephropathy 3