Hidradenitis suppurativa, often shortened to HS and also called acne inversa, is a long-lasting condition that causes painful lumps deep in the skin. It was once thought to be rare, but it affects at least 1 in 100 people when milder cases are counted. It usually starts between puberty and age 40, most often in the teens or twenties, and it affects at least three times as many women as men.
HS starts in hair follicles that become clogged and then burst under the skin. It is not caused by poor hygiene, it is not contagious, and it is not acne. It can run in families: 30 to 40% of people with HS have an affected relative, though many have none. Smoking is believed to be a common trigger. Obesity is another common trigger: excess weight raises both the risk of HS and the risk of severe HS.
What it looks like
HS begins where skin touches skin: the armpits, groin and inner thighs, and as it progresses, under the breasts. Before a lump appears, the area may itch, burn, swell or sweat more than usual. The first visible sign is often a painful spot that looks like a deep pimple or a boil.
Over time, more lumps can appear and merge into abscesses that burst and drain blood and pus, often with a strong odor. When the same areas heal and reopen again and again, tunnels can form under the skin, along with lasting scars. Breakouts often clear and then come back in the same place. Heat, sweating and friction from tight clothing tend to make it worse.
Anxiety and depression are more common with it, and people with HS may have a higher risk of arthritis, diabetes and heart disease. In long-standing HS there is also a higher risk of a type of skin cancer called squamous cell carcinoma, which is very treatable when found early.
When to see a dermatologist
- A tender, deep lump in the armpit, groin, inner thigh or under the breast.
- Lumps that keep coming back in the same areas.
- Lumps that drain, or wounds that do not heal or reopen after healing.
- Joint pain alongside HS.
Many people live with HS for years before anyone names it, and some visit the emergency room ten or more times first. Treatment that starts before HS worsens can reduce flare-ups and help prevent the scarring and pain that limit movement.
What happens at the visit
HS can look like acne, boils or herpes, so the dermatologist starts by sorting it out from those. Expect questions about where you get lumps, drainage or pain, when they started, and how they affect daily life. The dermatologist examines some or all of the affected areas. If a sore is draining, they may swab the fluid to check for infection. It can help to bring photos taken during a flare.
How dermatologists treat it
HS cannot be cured, but it can be controlled. The goals are fewer flares, healed wounds, less pain, and stopping the disease from getting worse. Plans are built around the type of lesions, whether there is pain or infection, and how HS affects daily life, and some combine medicine with an in-office procedure.
- Skin care. Gentle products and an antibacterial wash in place of anything irritating.
- Antibiotics. Applied to the skin for milder HS, or taken by mouth to reduce inflammation and bacteria.
- Hormonal therapy. Helpful for some women.
- Biologics. Medicines that target part of the immune system, used when other treatments have not worked, with close monitoring.
- In-office procedures. A corticosteroid injection to calm a painful early lump, and minor surgery under local numbing to drain a lump or remove an abscess, a tunnel or a lesion that keeps coming back. For some people, different lasers are used to remove affected tissue once the disease is stable on medicine.
- Laser hair reduction. Fewer hairs in affected skin can mean fewer lumps, with sessions every four to six weeks.
- Wound care and pain control. A dermatologist teaches how to dress draining wounds at home and helps manage pain.
Living with it day to day
Quitting smoking and losing excess weight can reduce flare-ups, and in some people HS has cleared after weight loss. Looser clothing helps when tight clothes set off a flare. Dermatologists advise people with HS never to wax, and to shave with care. Washing with an antimicrobial wash, and not scrubbing, protects irritated skin. A warm compress for about ten minutes, a few times a day, can ease a painful lump. Staying cool, and choosing an antiperspirant without alcohol, fragrance, dyes or baking soda, helps limit the sweat and heat that worsen HS. Counseling or a support group can help with the emotional side.
How to choose a dermatologist
Ask how many people with HS the practice treats and which in-office procedures they do themselves, such as drainage, removal of tunnels or laser hair reduction. Ask how they handle a painful flare between appointments. Check whether your insurance needs a referral from a family doctor and whether biologics need prior approval from your plan.
The city list below shows dermatologists who name hidradenitis suppurativa on their own websites.