A patient presents with a 12 hour history of a pruritic papular eruption arranged in a linear or flagellate pattern over his trunk. He has no other symptoms. He is otherwise healthy and is not on any medications. What did he eat yesterday that is the culprit?
Shiitake dermatitis occurs 12-60 hours after ingestion of raw or incompletely cooked shiitake mushrooms. The flagellate rash is characterized by multiple linear pruritic papules over the trunk and extremities. (Bachmeyer C et al. Shiitake dermatitis. CMAJ 2018; March 20; 189: E439. doi: 10.1503/cmaj.160644)