Linear porokeratosis: a case report

Porokeratosis is a rare genodermatosis based on chronic keratinization disorder histologically characterized by the presence of a cornoid lamella and various clinical manifestations. Five most commonly described types of poroketarosis are porokeratosis of Mibelli or ”classic” porokeratosis, disseminated superfi cial actinic porokeratosis, disseminated palmoplantar porokeratosis, linear porokeratosis, and punctate porokeratosis. In all of the fi ve clinical types of porokeratosis described today, cases of planocellular skin carcinoma are described, except in punctate type cases. Use of topical CO2 laser ablation, cryotherapy and topical use of 5% Imiquimod cream, have shown favorable effects in local treatment of porokeratosis. The authors present a clinical case of a girl suffering from linear porokeratosis over the course of the last four years, spreading on the inside of her right arm along the lines of Blaschko. Linear porokeratosis was histologically confi rmed by biopsy of skin lesions and dermoscopy. Dermoscopic fi ndings, used as an auxiliary method, also indicated linear porokeratosis. Successful liquid nitrogen cryotherapy prompted the authors to present a case in which the applied treatment proved to be successful, but also to emphasize the need for timely treatment in order to prevent malignant alterations of these changes.