The hyperpigmentation on both of this 56-year-old man’s legs is asymptomatic. But it has steadily worsened, causing him a great deal of distress.
A few months before the dyschromia manifested, he underwent orthopedic surgery and developed a postop infection. He was prescribed minocycline. As of today, he has been taking a 100-mg bid dose for three months.
He is otherwise healthy and not taking any other medications.
EXAMINATION
From the knees down, both legs display marked circumferential, bluish gray hyperpigmentation. It is not seen on any other areas (eg, arms, face, sclerae, or trunk).
What is the diagnosis?