Longitudinal melanonychia consecutive to nail biting.

Background, Melanonychia of the toenails sometimes results from repeated tr auma. This etiology is rarely put forward in lesions affecting the fingerna ils. Case report, A 44-year-old woman developed melanonychia affecting 9 fingern ails. Genetic predisposition and drug, hormonal or infectious causes were r uled out and we postulated that the lesions were induced by nail biting. Discussion. Nail biting is known to lead to several types of lesions, inclu ding melanonychia. The lesions may sometimes disappear several months after stopping this habit.