A novel splice mutation in the ATP2C1 gene in a woman with concomitant psoriasis vulgaris and disseminated Hailey–Hailey disease

Concurrent psoriasis vulgaris and Hailey–Hailey disease is very rare. The clinical and pathologic findings of widespread Hailey–Hailey disease in a 48-year-old woman with pre-existing generalized psoriasis vulgaris were described. In our patient, the vesicular eruption of Hailey–Hailey disease was obscured clinically by the psoriatic lesions. The diagnosis of both diseases was confirmed pathologically. The patient had a total of five skin biopsies performed over the neck, flank area, back, pubic area, and a finger. Acantholytic dyskeratosis, changes suggestive of Hailey–Hailey disease, were found in four specimens, psoriasis in two specimens, and both diseases in one specimen. The diagnosis of Hailey–Hailey disease was further confirmed by detecting a novel splice mutation (832G>A) in the ATP2C1 gene. Our case illustrated that diagnosis of disseminated Hailey–Hailey disease may easily be missed in a patient with a pre-existing generalized pruritic eruption, such as psoriasis. The appearance of eczematous vesicular eruption or eroded intertrigo-like lesions in a patient with pre-existing generalized eruption should raise a suspicion of Hailey–Hailey disease.