LAUSR

DEAR EDITOR, A 35-year-old man with verrucous porokeratosis, also known as porokeratosis ptychotropica, presented with well-demarcated, scaly, red–brown and verrucous plaques on his buttocks and lower extremities for 8 years (a). Histopathological examination (haematoxylin–eosin) revealed a digitate epidermis with columns of parakeratosis in the form of prominent cornoid lamellae, a diminished granular layer and a number of dyskeratotic keratinocytes (b). Dermoscopy of lesions revealed a papillomatous-like pattern, dotted and globular vessels, a brown band with white rims inside and outside of the band in the periphery, rosette sign and a central scar-like area (c, d). The patient was treated with acitretin 30 mg per day for 2 months. The skin lesions showed significant improvement. Verrucous porokeratosis can mimic psoriasis and is easily misdiagnosed clinically. Histopathological and dermoscopic examinations help to make a definitive diagnosis. Y . LUO J . L IU Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China 100730 Correspondence: Jie Liu. E-mail: [email protected]