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.
Hidradenitis suppurativa develops when hair follicles become blocked and inflamed. It’s not known why this blockage occurs, but a number of factors — including hormones, genetics, cigarette smoking and excess weight — may all play a role.
Hidradenitis suppurativa commonly occurs around hair follicles, where many oil and sweat glands are found, such as in the armpits, groin and anal area. It may also occur in areas where skin rubs together, such as the inner thighs, under the breasts or between the buttocks. Hidradenitis suppurativa can affect a single area or multiple areas of the body.
Signs and symptoms of hidradenitis suppurativa include:
- Blackheads. Small pitted areas of skin containing blackheads — often appearing in pairs or a “double-barreled” pattern — are a common feature.
- Red, tender bumps. These bumps, or lesions, often enlarge, break open and drain pus. The drainage may have an unpleasant odor. Itching, burning and excessive sweating may accompany the bumps.
- Painful, pea-sized lumps. These hard lumps, which develop under the skin, may persist for years, enlarge and become inflamed.
- Leaking bumps or sores. These open wounds heal very slowly, if at all, often leading to scarring and the development of tunnels under the skin.
Hidradenitis suppurativa often starts after puberty with a single, painful bump that persists for weeks or months. For some people, the disease progressively worsens and affects multiple areas of their body. Other people experience only mild symptoms. Excess weight, stress, hormonal changes, heat or excessive perspiration can worsen symptoms.
When to see a doctor
Mild cases of hidradenitis suppurativa may be treated with self-care measures. Consult your doctor if the condition:
- Is painful
- Doesn’t improve in a few weeks
- Returns within weeks of treatment
- Appears in several locations
- Recurs often