What is the initial management for a patient presenting with Henoch-Schönlein Purpura (HSP) rash, considering potential renal involvement and associated symptoms?

Management of Henoch-Schönlein Purpura (HSP) Rash

For patients presenting with HSP rash, supportive care is the primary intervention since the disease spontaneously resolves in 94% of children and 89% of adults, but immediate assessment for renal involvement is critical as this determines long-term prognosis and need for aggressive immunosuppression. 1

Initial Assessment and Monitoring

Obtain urinalysis immediately to detect proteinuria and hematuria, as 40-50% of HSP patients develop renal disease, which is the primary determinant of long-term outcomes. 1 End-stage renal disease occurs in 1-5% of patients, making early detection essential. 1

• Monitor for the classic triad: palpable purpura (present in 100% of cases), arthritis (75% of cases), and abdominal pain (60-65% of cases). 1, 2
• Recognize that adults are more likely to experience complications than children despite HSP being primarily a pediatric disease (>90% occur in children under 10 years). 1
• Document any antecedent upper respiratory illness, which is present in most cases. 1

Management Based on Disease Severity

Mild Disease (Rash and Arthritis Only, No Renal Involvement)

Provide supportive care as the primary intervention, including rest, hydration, and analgesics for joint pain. 1 The disease will spontaneously resolve in the vast majority of cases without specific treatment.

• Monitor urinalysis weekly for the first month, then monthly for 6 months to detect delayed renal involvement. 1

Moderate Disease (Abdominal Pain or Joint Symptoms)

Initiate oral prednisone 1-2 mg/kg daily for two weeks to treat abdominal and joint symptoms. 1 A meta-analysis demonstrated that corticosteroid use in children reduced the mean time to resolution of abdominal pain and decreased the odds of developing persistent renal disease. 1

• Continue supportive care measures alongside steroid therapy.
• Taper steroids after symptom resolution rather than abrupt discontinuation.

Severe Disease (Renal Involvement)

For HSP nephritis with persistent proteinuria, hypertension, or azotemia, consider renal biopsy to guide therapy, particularly when deciding between observation and immunosuppressive treatment. 3

Initiate combination therapy with corticosteroids plus an immunosuppressive agent (azathioprine, cyclosporine, tacrolimus, or mycophenolate mofetil/mycophenolic acid) for significant renal involvement. 3 The Canadian Society of Nephrology notes that practice patterns vary by center, with preference for steroid combinations rather than cyclophosphamide due to infertility and malignancy risks. 3

• Early aggressive therapy with high-dose steroids plus immunosuppressants is recommended for patients with severe renal involvement (nephrotic range proteinuria and/or progressive renal impairment). 1
• Mycophenolate mofetil has demonstrated efficacy in steroid-refractory cases with severe gastrointestinal involvement, achieving resolution within days. 4

Critical Pitfalls to Avoid

Do not dismiss the diagnosis based on absence of all classic features at presentation—the characteristic rash may emerge after other symptoms, and diagnosis becomes obvious only when the full constellation appears. 5 One case report documented severe abdominal pain with duodenal involvement before the rash developed. 5

Do not delay renal assessment—urinalysis showing proteinuria and hematuria requires immediate attention, as renal disease severity determines long-term prognosis. 6, 1 Long-term prognosis depends entirely on the severity of renal involvement. 1

Do not assume pediatric and adult HSP have the same prognosis—adults are more likely to experience complications despite the disease being more common in children. 1

Do not continue ineffective steroid therapy indefinitely in severe cases—for steroid-refractory disease with severe gastrointestinal or renal involvement, escalate to immunosuppressive agents rather than prolonging ineffective treatment. 4

Observation Period and Follow-up

There are currently no data to inform how long a patient should be observed for spontaneous remission before intervening with therapy or biopsy in cases of persistent proteinuria without other severe features. 3 Most clinicians would consider performing a biopsy in the presence of persistent proteinuria, hypertension, or azotemia. 3

Monitor for relapses, which can occur particularly during the first year of disease. 4 Immunosuppressive agents may be useful to induce and maintain remission not only in renal involvement, but in all cases of persistent, recurrent, or complicated HSP. 4