Papular acantholytic dyskeratosis of the vulva associated with familial Hailey-Hailey disease.

Papular acantholytic dyskeratosis (PAD) of the vulva is a rare, chronic disorder first described in 1984. It presents in young women as white to skin-coloured smooth papules over the vulva, which are persistent but asymptomatic. Histologically, there is hyperkeratosis and focal parakeratosis with acantholytic and dyskeratotic cells forming corps ronds and grains, placing PAD within Ackerman's spectrum of focal acantholytic dyskeratoses with Hailey-Hailey disease (HHD) and Darier disease. There have been 17 previous reports of PAD of the vulva, to our knowledge. Only one demonstrated a familial pattern, and none of the cases was associated with a family history of HHD. This is the first report of PAD and HHD in a single family, suggesting that PAD and HHD lie on a spectrum of disease and are genetically linked.