Photoletter to the editor: Hyperkeratosis lenticularis perstans (Flegel's disease) with unusual clinical presentation. Response to isotretinoin therapy.

Hyperkeratosis lenticularis perstans also known as Flegel's disease is a keratinisation disorder characterized by small keratotic papules with horny scales. Most cases have been reported in Europe with age of presentation between 35 and 60 years. We report a case of a 25-year-old man, who presented with 1-5 mm multiple asymptomatic hyperkeratotic papules of 15 years duration on both legs and hand along with lichenified plaques with Koebner phenomenon in the axillary folds, anticubital and popliteal fossae. Similar lesions were present in the eyelids also. There was no involvement elsewhere. Similar illness was found in the younger brother aged 13 years with the duration of illness for the past 5 years. Histopathology confirmed the clinical diagnosis. Patient was treated with oral isotretinoin in a daily dose of 20 mg per day to which he responded immediately with clearing of the lesions in two weeks.