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Updated: May 31, 2026

Laser Microdissection-Based Protocol for the LC-MS/MS Analysis of the Proteomic Profile of Neuromelanin Granules
Published on: December 16, 2021
Onychophagia-induced longitudinal melanonychia
Rachel B Anolik1, Kara Shah, Adam I Rubin
1Department of Dermatology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Abstract:
An otherwise-healthy 13-year-old girl with previously normal nails developed longitudinal pigmented bands on multiple fingernails. Physical examination revealed faintly pigmented bands on multiple fingernails and on the left fifth toenail. We believed that the cause of the pigmented bands was onychophagia-induced longitudinal melanonychia, a rare phenomenon, which emphasizes the need for dermatologists to question patients with melanonychia about their nail biting habits because they may not be forthcoming with this information.
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