Hereditary mucoepithelial dysplasia: unique histopathological findings in skin lesions

Hereditary mucoepithelial dysplasia (HMD) is a rare, autosomal dominantly inherited, multisystem disease thought to be caused by abnormalities in desmosomes and gap junctions. HMD affects the skin, mucosae, hair, eyes and lungs. Nearly all patients clinically display the triad of non-scarring alopecia, well-demarcated mucosal erythema and erythematous intertriginous plaques. Although histopathological findings of mucous membrane epithelium have been well characterized, only three reports have described histopathologic findings in the skin. We report a case with unique histopathological findings not previously reported in HMD.