Table 3

 Classification criteria for Henoch-Schönlein purpura

*Acute, any joint.
Palpable purpura (mandatory criterion) in the presence of at least one of the following four features:
• Diffuse abdominal pain
• Any biopsy showing predominant IgA deposition
• Arthritis* or arthralgia
• Renal involvement (any haematuria and/or proteinuria)