Table 1 Diagnostic criteria for Henoch-Schönlein purpura (HSP), as developed by EULAR/PRINTO/PRES [2]

Mandatory criterion

Purpura or petechiae with lower limb predominance

Minimum 1 out of 4 criteria

1. Diffuse abdominal pain with acute onset

2. Histopathology showing leukocytoclastic vasculitis or proliferative glomerulonephritis with predominant immunoglobulin A (IgA) deposits

3. Arthritis or arthralgia of acute onset

4. Renal involvement in the form of proteinuria or haematuria