• It often affects children and young adults.
• It usually starts following an upper respiratory tract infection.
Clinical Findings
• Skin involvement; The classic finding is palpable purpura. Rashes are more intense on the lower extremities.
• Joint involvement; it most commonly involves the knees and ankles (arthritis/arthralgia).
• GIS involvement; colic-style abdominal pain, intussusception, lower GI bleeding can be seen.
• Renal involvement; IgA nephropathy (hematuria, nephritic syndrome).
Laboratory Findings and Diagnosis
• Serum IgA levels may increase.
• Complement level and platelet count are normal.
• Biopsy shows leukocytoclastic vasculitis showing IgA deposition.
Treatment
• The disease is usually self-limited and heals without sequelae.
• Steroids are usually sufficient when needed (in severe GI and kidney involvement).
Some IgA-related diseases
IgA nephritis
IgA vasculitis (Henoch Schonlein purpura)
celiac disease
Dermatitis herpetiformis