Violaceous Patches in the Axilla

A man in his 40s presented with dark red, circular lesions in his right axilla without pain, blisters, or other symptoms; after resolution with a topical cream, similar lesions appeared in his left axilla and inguinal folds 5 months later. What is your diagnosis?

Source: JAMA Dermatology - July 25, 2018 Category: Dermatology Source Type: research