(BMJ)—A 48-yo man w/ type 2 DM presented w/ a 2-yr hx of asymptomatic spots on his shins. Exam: multiple pretibial patches that were irregularly shaped, pigmented, and atrophic. A few similar lesions were present on the forearms. What’s the dx?
Diabetic dermopathy
Necrobiosis lipoidica
Postinflammatory hyperpigmentation
Stasis dermatitis
Pigmented purpuric dermatosis
You are correct. Diabetic dermopathy (sometimes called shin spots) is seen in 17% to 40% of people w/ DM (type 1 and type 2). The condition can sometimes also be seen on the forearms. It’s assoc w/ increased age and longer DM duration and is believed to have a microangiopathic origin. It often occurs w/ other DM complications such as retinopathy and peripheral neuropathy.

BMJ 2018;363:k4882