Definition
A small vessel leucocytoclastic vasculitis with IgA1 immune complex deposition. It is the most common vasculitis of childhood.
Epidemiology
- Most cases occur between 3 and 15 years
- Often follows an upper respiratory infection, clustering in autumn and winter
Classification
- EULAR/PRINTO/PRES criteria require purpura or petechiae with lower limb predominance
- Plus one of abdominal pain, IgA on histology, arthritis or arthralgia, or renal involvement
Clinical Features
- Palpable purpura over the buttocks and extensor lower limbs
- Arthritis or arthralgia in about 80%, mostly knees and ankles
- Periarticular swelling and tenderness, often without a large effusion
- Oligoarticular, transient and non-deforming, settling within days to weeks
- Joint symptoms precede the rash in some children, causing diagnostic confusion
- Abdominal pain, gastrointestinal bleeding and intussusception
- Nephritis with haematuria or proteinuria in about 40%
- Scrotal swelling in boys
Investigations
- Platelets are normal, separating it from thrombocytopenic purpura
- Urinalysis and blood pressure at each review
- Skin or renal biopsy shows IgA deposition when the diagnosis is unclear
- Joint aspiration when septic arthritis cannot be excluded
Differential Diagnosis
- Septic arthritis in children, with a single hot joint, high fever, raised CRP and purulent aspirate
- Child with HSP arthritis is often well, with several joints and preserved movement
- Acute rheumatic fever
- Juvenile chronic arthritis
- Meningococcal sepsis with purpura fulminans
- Leukaemia with thrombocytopenic purpura
- Non-accidental injury
Management
- Supportive care. Rest, simple analgesia and NSAIDs for joint pain when renal function is normal
- Corticosteroids. For severe abdominal pain or orchitis, without preventing nephritis
- Renal surveillance. Urinalysis and blood pressure for at least 6 months
Prognosis
- Self-limiting in most, with recurrence in about one third
- Long term outcome depends on renal involvement
References
- Ozen S, Pistorio A, Iusan SM, Bakkaloglu A, Herlin T, Brik R, Buoncompagni A, Lazar C, Bilge I, Uziel Y, Rigante D, Cantarini L, Hilario MO, Silva CA, Alegria M, Norambuena X, Belot A, Berkun Y, Estrella AI, Olivieri AN, Alpigiani MG, Rumba I, Sztajnbok F, Tambic-Bukovac L, Breda L, Al-Mayouf S, Mihaylova D, Chasnyk V, Sengler C, Klein-Gitelman M, Djeddi D, Nuno L, Pruunsild C, Brunner J, Kondi A, Pagava K, Pederzoli S, Martini A, Ruperto N. EULAR/PRINTO/PRES criteria for Henoch-Schönlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arteritis. Ankara 2008. Part II. Final classification criteria. Ann Rheum Dis. 2010, 69(5), 798-806. PubMed
- Ozen S, Marks SD, Brogan P, Groot N, de Graeff N, Avcin T, Bader-Meunier B, Dolezalova P, Feldman BM, Kone-Paut I, Lahdenne P, McCann L, Pilkington C, Ravelli A, van Royen A, Uziel Y, Vastert B, Wulffraat N, Kamphuis S, Beresford MW. European consensus-based recommendations for diagnosis and treatment of immunoglobulin A vasculitis-the SHARE initiative. Rheumatology (Oxford). 2019, 58(9), 1607-16. PubMed
- Saulsbury FT. Henoch-Schönlein purpura in children. Report of 100 patients and review of the literature. Medicine (Baltimore). 1999, 78(6), 395-409. PubMed
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 19 October 2026.