Abstract

Case presentation: An otherwise previously healthy 19-year-old man presented with complaints of multiple warts in his left inguinal fold for a period of 3 years. During this period, the patient used multiple OTC treatments on the lesions without improvement. He subsequently presented to his primary care provider, was tested with negative results for STDs and was treated by cryotherapy with no effect. Dermatological examination revealed verrucous nodules in a linear systematized distribution throughout the inguinal fold extending to the left thigh and scrotum. Clinical suspicion was for verruca vs inflammatory linear verrucous epidermal nevus (ILVEN) vs verrucous carcinoma vs Bowen’s Disease. Biopsy revealed multiple parakeratotic columns of cornoid lamella with underlying scattered dyskeratotic epidermal keratinocytes. A diagnosis of porokeratosis ptychotropica was made. Discussion: Porokeratosis ptychotropica is a rare and under?recognized variant of genitogluteal porokeratosis. First described in 1995 by Lucker et al (1), fewer than 50 cases had been reported by 2018 (2). It is characterized by verrucous papules and plaques confined to the body folds, classically located in the genitogluteal area. Typical histological features of multiple coronoid lamellae create the keratotic or verrucous appearance and expansile papular growth of the lesions. The pathogenesis of the disease remains unknown, but malignant transformation can occur in up to 11% of cases (3). Because of the rarity of the disease, missed or delayed diagnosis of the verrucous lesions is frequent. It is important to distinguish this disease in order to avoid painful or traumatic procedures, as well as to survey for potential malignant transformation. Here, we report a case of a 19-year-old with porokeratosis ptychotropica with 3 years of ineffective treatment.

Financial Disclosure:
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