Henoch-Schönlein purpura
Pronunciation: HEN-ok SHERN-line
An IgA-mediated vasculitis affecting small vessels, commonly causing nephritis in children along with skin, joint, and gastrointestinal manifestations.
Full Definition
Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis in children, characterized by IgA immune complex deposition in small vessels. The classic tetrad includes palpable purpura on the lower extremities, arthritis or arthralgia, abdominal pain, and nephritis. Renal involvement occurs in 20-60% of cases and may range from isolated hematuria to rapidly progressive glomerulonephritis. Long-term prognosis is generally excellent, but persistent nephritis may lead to chronic kidney disease. The condition typically follows an upper respiratory infection and shows seasonal clustering in autumn and winter.
Usage
Usage note: Note the recent terminology change to IgA vasculitis in some guidelines, though HSP remains widely used.
In Context
- "The diagnosis of Henoch-Schönlein purpura was confirmed by the presence of palpable purpura and microscopic hematuria." — Clinical assessment
- "Follow-up urinalysis at 6 months post-HSP onset showed resolution of proteinuria and hematuria." — Long-term monitoring report