Hidradenitis suppurativa (hi-drad-uh-NIE-tis sup-yoo-ruh-TIE-vuh) is a chronic skin condition that features pea-sized to marble-sized lumps under the skin. Also known as acne inversa, these deep-seated lumps typically develop where skin rubs together — such as the armpits, groin, between the buttocks and under the breasts.
The lumps associated with hidradenitis suppurativa are usually painful and may break open and drain foul-smelling pus. In many cases, tunnels connecting the lumps will form under the skin.
Hidradenitis suppurativa tends to start after puberty, persist for years and worsen over time. Early diagnosis and treatment of hidradenitis suppurativa can help manage the symptoms and prevent new lesions from developing.