treatment of occupational koilonychia with tazarotene gel

Sir, Koilonychia is a syndrome characterized by eversion of the edges of the nails, while the central portion of the nail becomes concave. This dystrophy usually involves several fingers, especially the thumb. The underlying tissues may either be healthy or affected by subungual hyperkeratosis. Classification of koilonychia includes idiopathic forms (hereditary and congenital, sometimes associated with other anomalies) as well as acquired forms (secondary to avitaminoses, dermatoses, kidney transplantation, carpal tunnel syndrome, cardiovascular and haematological disorders, infections, endocrine disorders, traumatic and occupational forms) (1). The first three digits are frequently involved in occupational forms of koilonychias, probably because they are more exposed to pressure during handwork (1). Tazarotene is an acetylenic retinoid selective for retinoic acid receptors (RARa) and is approved as a topical treatment for psoriasis (2). It has a strong antiproliferative effect and it modulates keratinocyte differentiation (3). We present a case of occupational koilonychia treated with tazarotene 0.1% gel