Discoloration of nail plates. Many chemicals can discolor nail plates. Solutions of potassium permanganate and silver nitrate stain nail plates brown-purple and jet black, respectively. In the case illustrated here, the stain derived from resorcinol. Such stains are harmless and can be easily removed by superficial scaling with the edge of a glass slide.
Color Atlas of Pediatric Dermatology
Samuel Weinberg, Neil S. Prose, Leonard Kristal
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