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Definition
By Mayo Clinic staff

Lichen nitidus is a rare, noncancerous skin condition. It consists of tiny, skin-colored bumps (papules) that often appear in clusters on the surface of your skin, especially on your trunk and upper extremities. The cause of lichen nitidus is unknown.

Lichen nitidus may affect anyone, but typically develops in children and young adults. While you may find lichen nitidus to be annoying, it's harmless. Even without treatment, lichen nitidus usually disappears over time.