Twenty nail dystrophy associated with lichen planus in a child: A case report

Twenty nail dystrophy (tnd) is a rare acquired idiopathic nail dystrophy characterized by excess longitudinal ridging, distal notching, splitting, loss of nail luster and thinning of nail plates that may affect 1 to 20 nails. it occurs as a common manifestation of various dermatoses affecting the nail unit like lichen planus, psoriasis, atopic dermatitis, onychomycosis, vitiligo and alopecia areata, but isolated cases without an associated disease are rare. tnd is a manifestation of diverse underlying processes; therefore its histology will vary; however, histologic data on tnd are only available in very few published reports. we are documenting the histologic features of tnd in a 12-year-old boy who presented with thin rough opaque lusterless nail plates with longitudinal ridging of the twenty nails without any systemic involvement.