Cocaine and Levamisole Induced Vasculitis.

Levamisole adulterated cocaine is a rare cause of anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis. It is increasingly diagnosed because of raised awareness; however, it is still underdiagnosed in part because of its rarity and patients not reporting cocaine use. Here we report a case of levamisole-induced vasculitis. We present a 48-year-old non-Hispanic white male with a past medical history significant for Crohn's Disease and pneumonia who presented with acute bilateral ear pain and rash. His urinary drug screen was positive, which prompted suspicion of contamination and potential levamisole adulterated cocaine-associated vasculitis. A punch biopsy showed evidence of leukocytoclastic vasculitis and multiple fibrin thrombi further supporting contamination with levamisole. We believe this case highlights the importance of using patient history in guiding diagnostic testing in the setting of acute vasculitis. Once the history of illicit substance use was confirmed, our differential diagnosis and considerations for treatment significantly changed.