Make the Diagnosis: Pigmentation Changes in a Young Woman with T1D

(MedPage Today) — A 17-year-old woman with a history of type 1 diabetes went to her dermatologist after she noticed that the skin on the back of her hands was changing color. Her normally dark-skinned hands now had hypopigmented patches. It seemed to happen slowly over several months, but now there was no mistaking the change. The lesions were not accompanied by any other physical symptoms.

Can you diagnose the patient?
Source: Dermatology