What is the treatment approach for Henoch-Schonlein purpura (HSP)?

Henoch-Schönlein Purpura Treatment Approach

Initial Management Strategy

For most children with HSP, treatment is supportive only, focusing on symptom control with acetaminophen for pain, while avoiding NSAIDs like ketorolac due to renal toxicity risk. 1

Symptomatic Treatment

• Use acetaminophen (paracetamol) as first-line analgesic for joint pain and general discomfort, avoiding NSAIDs which can cause acute kidney injury in patients with potential renal involvement 1
• For severe joint pain or cutaneous symptoms, oral prednisone 1-2 mg/kg daily for two weeks may be beneficial 1
• Oral corticosteroids are indicated for severe gastrointestinal pain and gastrointestinal hemorrhage, but should not be used universally in all HSP patients 2
• Colchicine (1 mg/day) may be considered for persistent purpura and pain, with treatment for at least six months 1

What NOT to Do for Prevention

Do not use corticosteroids prophylactically at HSP onset to prevent nephritis - moderate quality evidence (Level 1B) shows no benefit in preventing nephritis or reducing risk of severe persistent nephritis 1, 3, 2. Multiple studies confirm that early steroid treatment does not reduce the incidence and severity of nephropathy in children with HSP 2.

Renal Disease Monitoring and Management

Initial Assessment

• Perform urinalysis with microscopy at presentation, looking specifically for proteinuria, red blood cell casts, and dysmorphic red blood cells 1
• Obtain basic metabolic panel including BUN, serum creatinine, and complete blood count with platelets 1
• Measure blood pressure as hypertension indicates more severe renal involvement 1
• A normal urinalysis on day 7 has a 97% negative predictive value for normal renal outcome 4

Monitoring Protocol

• Monitor all HSP patients for six months with urine testing, prioritizing intensive monitoring for those with abnormal urine findings on day 7 4
• Continue monitoring for persistent hematuria and proteinuria as indicators of ongoing disease activity 1

Treatment Algorithm for HSP Nephritis

Mild Proteinuria (Persistent but <1 g/day/1.73 m²)

• Start ACE inhibitor or ARB therapy for persistent significant proteinuria, even though evidence is extrapolated from IgA nephropathy rather than HSP-specific trials 1, 5
• Titrate to maximum tolerated dose targeting blood pressure <120 mmHg systolic 5
• Continue optimized supportive care for at least 90 days before considering immunosuppression 5
• Restrict dietary sodium to <2.0 g/day to maximize antiproteinuric effect 5

Moderate Proteinuria (>1 g/day/1.73 m² after ACE inhibitor/ARB trial)

• For children with persistent proteinuria >1 g/day per 1.73 m² after ACE inhibitor/ARB trial and GFR >50 ml/min per 1.73 m², use a 6-month course of corticosteroid therapy 1
• Target proteinuria to <1 g/day/1.73 m² rather than attempting complete normalization 1
• Reserve corticosteroid therapy for nephrotic syndrome (proteinuria >3.5 g/day) or nephritic syndrome that has not improved with ACE inhibitor/ARB therapy 1

Severe Nephritis (Crescentic HSP with nephrotic syndrome and/or deteriorating kidney function)

• Treat with high-dose intravenous methylprednisolone plus cyclophosphamide, following the same protocol as crescentic IgA nephropathy 1, 6
• Alternative immunosuppressive options include steroids combined with azathioprine, cyclosporine, tacrolimus, or mycophenolate mofetil/mycophenolic acid 1
• Cyclophosphamide is used less frequently due to side effects 1

Adult HSP Nephritis

• Treat adults with HSP nephritis using the same approach as children, though adults have worse prognosis and higher risk of progression to end-stage renal disease 1, 6

Common Pitfalls to Avoid

• Do not start corticosteroids too early for mild proteinuria without adequate trial of ACE inhibitor/ARB therapy 1
• Do not attempt to normalize proteinuria to <0.5 g/day/1.73 m², which increases side effects without proven benefit 1
• Do not use mycophenolate mofetil (MMF) as evidence shows no benefit in IgA nephropathy 5
• Accept modest increases in serum creatinine up to 30% during ACE inhibitor/ARB uptitration, as this reflects appropriate hemodynamic changes 5

Adjunctive Supportive Measures

• A low-antigen-content (LAC) diet may improve symptoms and laboratory abnormalities when strictly followed for 4-8 weeks 1
• The LAC diet can be used in conjunction with other treatments for chronic or persistent symptoms 1

Prognosis

• Most cases are self-limited with average disease duration of 4 weeks 2
• Approximately 2% of children with HSP progress to renal failure 6
• Up to 20% of children with nephritis treated in specialized centers require hemodialysis 6
• Renal involvement is the most important prognostic factor determining morbidity and mortality 2
• Older patients are at higher risk of requiring renal referral 4