Idiopathic pustular vulvitis.

A 31-year-old woman presented in the 23rd week of her third pregnancy with extremely painful pustular vulvitis, unresponsive to antibiotics. Although the histological findings were was consistent with a diagnosis of hidradenitis suppurativa (HS), bridged comedones, the hallmark of this disease, were absent and there were no dermal sinuses. Incision and drainage of the pustules provided only temporary improvement, which was briefly maintained with oral clindamycin and topical steroids. After the birth, a course of isotretinoin produced almost total clearance, a response not typically found in HS. This patient's condition may represent a variant of HS, and if so, it would be the first case report of de novo HS in pregnancy, but its clinical features and evolution differed so much from those in HS that the possibility of a previously unrecognised condition cannot be excluded.