DermATOM

9-year-old female presents to the dermatology clinic with persistent rough, dry patches on the upper arms that her mother noticed two years ago. The mother is concerned because the texture resembles “goosebumps” and seems more pronounced in colder weather. Despite using various moisturizers and soaps, there has been no improvement. The mother reports no associated redness, pain, or itching. The child’s medical history is unremarkable, with no known allergies, eczema, or recent illnesses.

History A 74-year-old woman presents with a 1-year history of a lesion on the dorsum of her middle finger. This has gradually increased in size over the last 12 months and is asymptomatic. Previously she had a similar lesion on her left leg, which had been treated successfully 18 months ago. She lived abroad as a child and is a keen gardener. She is otherwise well and takes 75 mg aspirin daily.   Examination There is an erythematous plaque 1 cm in size with overlying scale on the dorsum of her middle finger, the surrounding skin being normal.