Hypopigmented Segmental Darier Disease

BACKGROUND: Darier disease is a genodermatosis caused by a mutation in the ATP2A2 gene. It classically presents as hyperkeratotic greasy papules in a seborrheic distribution. Several variants have been reported, notably the hypopigmented variant, which predominantly targets dark-skinned individuals, and a segmental variant that often follows the lines of Blaschko. METHODS: We report a case of a 41-year-old African-Canadian female with a long-standing history of macular hypopigmented pruritic eruption following the lines of Blaschko on her back. The eruption was persistent and recalcitrant to various treatments. Dyskeratosis with corps ronds and grains, acantholysis, and parakeratosis were observed on histopathology. Those findings were consistent with the diagnosis of segmental hypopigmented Darier disease. RESULTS AND CONCLUSIONS: To our knowledge, this is the first case reporting a combined segmental and hypopigmented variant of Darier disease. We further present a literature review for hypopigmented and segmental variants of Darier disease.