Supplementary Material for: Suspected Alcohol-Induced IgA Vasculitis: A Case Series and Review of the Literature

Introduction:
IgA vasculitis is a small-vessel leukocytoclastic vasculitis marked by IgA-dominant immune complex deposition, typically affecting the skin, joints, gastrointestinal tract, and kidneys. While common triggers include infections and medications, alcohol is a rarely reported precipitant. Its role remains unclear but may involve mucosal immune dysregulation, impaired IgA clearance, and increased immune complex formation.

Case Presentations:
We report two adult patients with biopsy-proven IgA vasculitis presenting with recurrent lower extremity purpura. Both experienced disease flares closely following alcohol consumption and showed limited response to colchicine. Systemic involvement was absent, and laboratory evaluations were largely unremarkable. Notably, symptom resolution or marked improvement occurred with alcohol avoidance.

Conclusion:
These cases support a potential link between alcohol consumption and recurrent IgA vasculitis flares. Recognizing alcohol as a possible trigger may improve disease control and highlights the importance of thorough exposure histories in dermatologic assessment.