Abstract

Syringometaplasia describes a benign reactive change which occurs to the eccrine ducts and glands. The underlying pathogenesis is not well understood, but various potential contributing factors have been described, such as infection, inflammation, and medications. Only several recent reports of mucinous syringometaplasia have been described in the literature, adding to a handful of cases published in the 1980s and 1990s. We describe an additional case and review the literature in order to increase awareness of this rare entity. A 65-year-old man presented with an 8 mm verrucous skin-colored papule on the right first finger. The clinical differential diagnosis included a verruca vulgaris and a prurigo nodule. A shave biopsy was performed, and histopathologic evaluation confirmed a diagnosis of mucinous syringometaplasia. Mucinous syringometaplasia often presents as a warty papule or nodule on an acral location, similar to our case, but has also been described on other sites including the face, neck, and genitalia. Some lesions have been reported to contain a central pore which drains serous fluid. Histologic features of mucinous syringometaplasia include epidermal invagination, creating the pore-like structure which can be observed, with an epithelium consisting of squamous cells and mucin-containing goblet cells surrounding an eccrine structure. The lesions can be treated with excision and typically do not subsequently recur.