EULAR classification criteria for IgAV are as follows: mandatory criteria (non-thrombocytopenic palpable purpura, predominantly in the lower limbs plus one of the four criteria, viz., renal manifestations, abdominal pain, arthralgia/arthritis, and leukocytoclastic vasculitis with IgA deposits in the skin biopsy). Here, CD79A is linked to arthritic joint disease.