Discolored patches from wrist to elbow

A girl, aged 11 years, presented to the dermatology clinic with complaints of a slowly spreading discoloration on her right arm. The discoloration started six months earlier as a small dark patch on her dorsal wrist and spread upward toward the elbow. She was previously treated for a presumed fungal infection with a topical antifungal and a medium-potency topical steroid. ...