Hidradenitis Suppurativa (also known as Apocrinitis, Apocrine Acne, Verneuil's disease, Velpeau's disease, Fox-den disease, Pyodermia sinifica fistulans and Acne inversa) is an uncommon skin disorder characterized by the eruption of painful lesions predominantly under the arms and in the groin area. As a disease of the hair follicle, it is related to other follicular diseases, such as acne or pilonidal cyst.