Twenty nail dystrophy trachyonychia: an overview.

Twenty nail dystrophy (TND) trachyonychia, a fascinating clinical condition, was brought to focus 25 years ago. Ever since, it has been sparingly reported. Nonetheless, the condition is well-recognized and its diagnosis is made on the basis of clinical features characterized by onset in infancy/childhood, and occasionally in adults. The lesions are fairly representative, and are characterized by the alternating elevation and depression (ridging) and/or pitting, lack of luster, roughening likened to sandpaper, splitting, and change to a muddy grayish-white color. Dystrophy is prominent. Several modes of occurrence have been described including an hereditary component. The confirmation of diagnosis is through microscopic pathology corresponding either to endogenous eczema/dermatitis, lichen-planus like or psoriasic-form. It is a self-limiting condition and may occasionally require intervention.