This autoimmune disease attacks color-producing cells.

Hints:

• May be seen with other autoimmune diseases, such as thyroid disease and alopecia areata.
   

• Sharply defined patches devoid of color are seen on the skin, and if the affected area bears hair, the hair may turn white as well.
   

• Most commonly affects areas of injury, particularly on the face, upper chest, hands, armpit, and groin.

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