Palmoplantar keratoderma and leukokeratosis anogenitalis: the second case of a new disease

An increasing number of syndromes with palmoplantar keratoderma (PPK) with associated diseases are being identified, representing a wide spectrum of distinct entities. At present only one case report has described the combination of marked anogenital leukokeratosis with diffuse PPK evolving in a collodion baby. We report a patient with a diffuse, nonprogressive PPK in combination with an intermittently pruritic, slowly progressive anogenital leukokeratosis. Hyperkeratosis of the perineal area was most pronounced and extended to the distal portion of the anal mucosa. The opalescent lesion was also visualized at the margin of the major labia. Vulvar structures were not otherwise involved or dystrophic. There were no signs or symptoms of ectodermal dysplasia. Specifically, the nails were normal and showed no signs of pachyonychia congenita. Other differential diagnoses included dyskeratosis congenita and white sponge nevus, which may be associated with anogenital leukokeratosis, but a keratoderma is not associated with these entities. Keratin immunocytochemistry showed marked expression of suprabasal K17 and absence of K6 and K16. Further examination of the initial case described by Itin and Rufli demonstrated the same expression pattern and supports the contention that these two cases represent the same entity.