Detection of human papillomavirus and response to topical 5% imiquimod in a case of stucco keratosis

Stucco keratosis is a skin disorder with papular warty lesions that usually appear on the lower limbs in elderly people. The aetiology, pathogenesis and treatment is still a matter of debate. We report a 75-year-old non-immunosuppressed man with extensive lesions all over his body, which had not responded to curettage or electrodesiccation. To determine the possible role of human papillomavirus (HPV) in stucco keratosis, we used nested polymerase chain reaction (PCR) to identify HPV DNA in the lesions. To include a broad range of both cutaneous and mucosal HPV types, PCR was performed with two sets of degenerate primers. Using this approach we detected HPV types 9, 16, 23b, DL322 and a variant of HPV type 37 in multiple stucco keratoses. Imiquimod (5% cream), a new compound that modifies the immune response by stimulating production of cytokines, applied overnight, three times a week for 5 weeks, resulted in resolution of all treated lesions.