Herpes Labialis–Induced Lip Leukoderma

A 45-year-old man presented with slowly progressive discoloration of the lips over 30 years. The patient recalled tiny blisters appearing in many but not all areas prior to discoloration. Physical examination revealed well-defined, irregularly shaped, depigmented patches limited to the dry mucosal and adjacent cutaneous portions of the lips. The differential diagnosis included vitiligo, contact leukoderma, discoid lupus erythematosus, and lip leukoderma secondary to recurrent herpes labialis infection.