What is the workup for Henoch-Schönlein Purpura (HSP)?

From the Guidelines

The workup for Henoch-Schönlein purpura (HSP) should include a comprehensive clinical evaluation, laboratory tests, and sometimes imaging studies, with a focus on detecting renal involvement and guiding treatment decisions.

Initial Evaluation

The initial evaluation should include:

• A complete blood count
• Urinalysis to detect hematuria or proteinuria
• Renal function tests (BUN, creatinine)
• Inflammatory markers (ESR, CRP)
• Coagulation studies (PT, PTT) and stool guaiac to evaluate for GI bleeding
• Serum IgA levels, although they may not be diagnostic
• Consideration of ANCA, ANA, and complement levels to exclude other vasculitides

Diagnostic Confirmation

A skin biopsy showing leukocytoclastic vasculitis with IgA deposits can confirm the diagnosis, but it is not always necessary with a classic presentation 1.

Renal Involvement

Renal biopsy is indicated for significant proteinuria (>1g/day), declining renal function, or persistent hematuria beyond 6 months, as suggested by the 2012 KDIGO clinical practice guideline for glomerulonephritis 1.

Imaging Studies

Abdominal ultrasound or CT may be warranted for severe abdominal pain to rule out intussusception.

Treatment Guidance

This comprehensive approach helps confirm HSP diagnosis and identify organ involvement, guiding treatment decisions which typically include supportive care, NSAIDs for joint pain, and sometimes corticosteroids for severe manifestations, with consideration of angiotensin blockade in children with HSP and persistent significant proteinuria 1.

From the Research

Diagnosis of Henoch-Schönlein Purpura (HSP)

• The diagnosis of HSP can be challenging, and a skin biopsy should be performed for histological and immunofluorescence studies in cases of clinical suspicion of HSP 2.
• A skin biopsy is rarely necessary for diagnosis in children, but may be needed in very young age children and adults where the rash is not classically distributed 3.
• The clinical picture of HSP is often incomplete, and renal signs can become manifest years after initial signs, making it important to correctly diagnose HSP from the initial signs 2.

Diagnostic Tests

• Abdominal contrast-enhanced computed tomography (CT) examination and small intestinal enteroscopy can be used to evaluate the intestinal involvement in HSP 4.
• Renal needle biopsy with immunofluorescence and pathologic examinations can be used to evaluate the renal involvement in HSP 4.
• Urine testing for proteinuria and haematuria, and blood pressure measurement can be used to monitor the renal disease in HSP 5.

Diagnostic Criteria

• The diagnosis of HSP is based on the presence of IgA deposits in vessel walls associated with the characteristic signs of small-vessel vasculitis 2.
• Higher IgA levels with multiorgan involvement (gastrointestinal, kidney, and skin) should make one consider the diagnosis of HSP 4.
• The typical skin manifestation of HSP is distributed purpura in dependent areas, and abdominal pain, gastrointestinal tract bleeding, and urine protein can also be present 4.