Hidradenitis suppurativa (HS) is a disease that usually begins as pimple-like bumps on the skin. The pimple-like bumps tend to develop in places that everyday pimples do not appear. HS is most common on the underarms and groin.
Getting treatment for HS is important. Early diagnosis and treatment can prevent HS from worsening.
If HS worsens, the pimple-like bumps can grow deep into the skin and become painful. They can rupture, leaking bloodstained pus onto clothing. This fluid often has a foul odor.
As the deep bumps heal, scars can form. Some people develop tunnel-like tracts under their skin. As the skin continues to heal and scar, the scars thicken. When thick scars form in the underarm, moving the arm can be difficult. Thick scars in the groin area can make walking difficult.
Because HS can look a lot like acne, folliculitis, or boils, it is best to see a dermatologist for a diagnosis. To a dermatologist’s trained eye, the differences between HS and other skin diseases are subtle but obvious. Proper treatment depends on an accurate diagnosis. Hidradenitis suppurativa: In its earliest stage, HS often looks like boils or pimples (left), but with time thick scars can form.
If you have this skin disease, you may notice breakouts on your skin that look like pimples or boils. Your skin may clear for a while, but you notice new breakouts develop in the same area.
Unlike everyday pimples, hidradenitis suppurativa (HS) forms in areas where skin touches the skin.
HS is most common in these areas:
Underarms (one or both)
Groin (genitals, around the anus, and surrounding area)
Women’s breasts (underneath and sometimes on the breasts)
Although rare, a few studies have found HS near an ear or around the bellybutton. There have also been a few cases of HS appearing on the face, neck, or back.
Women tend to get breakouts on their genitals and upper thighs. Men are more likely to have HS on their genitals and around the anus.
Some people develop breakouts in the exact same spot each time. For others the breakouts appear in the same area, but never seem to be in the exact same spot.
Early signs and symptoms
Some people say that their HS looks like one of these skin conditions:
Deep-acne like cysts and blackheads
Folliculitis (looks like swollen pimple with a hair in the center)
When people first get hidradenitis suppurativa (HS), they often see:
One (or several) breakouts that look like pimples or boils
Breakouts may stay on the skin; sometimes, they clear and reappear
Later signs and symptoms
Without treatment, HS can worsen. If this disease progresses, the person may develop:
Painful, deep breakouts that heal and reappear
Breakouts that rupture and leak a foul-smelling fluid
Scars that form as breakouts repeatedly heal and reappear
Scars that become thicker with time
Skin that begins to look spongy as tunnel-like tracts form deep in the skin
Skin cancer (rare)
Signs and symptoms can change
The signs and symptoms of HS can change quickly. One week, a person may have a foul-smelling fluid leaking from breakouts. The next week, the breakouts have cleared and scars are the only sign of HS.
Some people always have breakouts on their skin.
Skin cancer risk
HS develops on skin that tends to get little or no direct sunlight. Yet, a few people have developed squamous cell carcinoma, a common type of skin cancer, where they had HS breakouts and scarring for years. Most cases developed in men who had long-standing HS on their genitals or around their anus.
Treatment helps prevent long-standing HS.
Quality of life affected
Without treatment, HS can continue its cycle of breakouts and healing. As the breakouts clear, scars form. Continual healing and scarring can cause hollow passages called fistulas to develop inside the body. Fistulas can be painful and require surgery to repair.
People who have a foul-smelling liquid draining from the breakouts can feel embarrassed. They may feel too embarrassed to see a doctor. Dermatologists understand this. You should not feel embarrassed to see a dermatologist about this problem.
Causes and Risk Factors
Who gets hidradenitis suppurativa?
Hidradenitis suppurativa (HS) is most common in:
Overweight or obese people
Women (3 times more common in women than men).
HS usually begins around puberty. Few people develop HS before 11 years of age. When HS appears before 11 years of age, the child is usually experiencing early puberty. Getting HS after menopause or 55 years of age is rare.
What causes hidradenitis suppurativa?
No one knows for sure what causes HS. Because it occurs after puberty, hormones likely play a role. The person’s immune system also seems to play a role.
It is possible that HS develops when the person’s immune system overreacts. HS begins in the hair follicles (where hair grows out of the skin). Like everyday acne, HS forms when the hair follicles clog with bacteria and other substances. It is possible that HS develops in people who have an immune system that overreacts to the plugged hair follicle.
Lifestyle also seems to play a role. It seems that smoking, being overweight, or taking lithium may trigger HS. These things do not cause HS. If a person is susceptible to getting HS, any of these could make HS appear for the first time or worsen existing HS.
Although the exact cause is still unknown, dermatologists have learned the following from studying HS:
It is not contagious.
Poor hygiene does not cause HS.
About one-third of people who get HS have a blood relative who has HS.
Diagnosis and Treatment
How do dermatologists treat hidradenitis suppurativa?
Dermatologists offer patients who have hidradenitis suppurativa (HS) many treatment options, including many different medicines. Surgery may be an option when HS is severe or fails to respond to other treatment.
Treatment can help patients with HS:
Clear or reduce breakouts.
Get rid of scars and tunnels beneath the skin.
Prevent new breakouts.
Dermatologists frequently use the treatments listed below, so they have in-depth knowledge and experience using them.
Medicines used to treat HS- If you have HS, your dermatologist may include one or more of the following in your treatment plan:
Antibiotics: This is often part of the treatment plan. These drugs can reduce inflammation, fight infection, prevent HS from worsening, and stop new breakouts.
Acne washes and medicines: Acne treatments that you can buy without a prescription may be helpful. Using these products alone usually will not clear HS.
Bleach baths: If certain bacteria colonize (found on the surface of your skin) you, your dermatologist may recommend taking 5- or 10-minute bleach baths. You’d take this bath in your own bathtub at home. If a bleach bath is right for you, your dermatologist will tell you how to make one.
Biologic is the first FDA-approved treatment for HS
The U.S. Food and Drug Administration (FDA) approved the first treatment for HS in 2015. It is a biologic called adalimumab (a dal aye’mu mab). In studies, the patients who received adalimumab had noticeably fewer abscesses and nodules.
The FDA has approved adalimumab for adults who have moderate (Hurley stage II) or severe (Hurley stage III) HS.
Biologics: These work on the immune system. Some, such as adalimumab, you inject yourself. Others require an infusion at a hospital or clinic. Some patients have seen long-term clearing of their HS with a biologic. Due to possible serious side effects, you should discuss the risks and benefits with your dermatologist.
Corticosteroid injection into a breakout: Your dermatologist may inject this into a painful cyst to reduce pain and swelling.
Corticosteroid pills: This medicine reduces inflammation, which can help clear HS and prevent new breakouts.
Diabetes drug: Metformin has been approved to treat adult-onset diabetes. It may also help people who have HS and a condition called metabolic syndrome.
Hormone therapy: Some women who have HS get relief by taking birth-control pills, a medicine called spironolactone, or another medicine that regulates hormones. These medicines can decrease pain and the amount of fluid draining from the breakouts.
Methotrexate (severe HS only): This medicine is used to treat cancer and certain other medical conditions, such as severe psoriasis. It works on the immune system and may help control HS in some patients.
Oral retinoid: A few patients with HS are helped.
Radiation therapy: This treatment exposes the body to radiation, so it is used less often today than in the past. Some patients have seen their HS clear. Be sure to talk with your dermatologist about the short- and long-term risks to your body.
Wound dressings: If the HS causes tunnels beneath your skin, you will need to treat these as you would wounds.
Surgical treatment for HS
When HS grows deep into the skin, medicine alone may not be effective. Your dermatologist may recommend a surgical procedure.
The following can be performed in a dermatologist’s office or clinic:
Laser surgery: This treatment is showing promise. Some patients clear after several treatments. Lasers are proving effective at clearing new and deep HS breakouts. This treatment may be helpful because it destroys the hair follicles.
Deroofing: This surgery may be an option for patients who have painful HS that repeatedly returns. The surgeon turns deep, painful HS into scars.
Drain or incise: During the surgery, the dermatologist drains 1 or 2 lesions or cuts them out. This can bring short-term relief, but the HS can return.
Excision: This involves surgically cutting out the HS and some normal-looking skin. Because the wound is deep, the area needs to be covered with a skin graft (skin removed from another part of your body) or skin flap (skin from nearby is pulled over to cover the wound). HS does not return to the treated area, but it can develop nearby.
No one treatment works for everyone who has HS. Sometimes, a patient needs to try a few different treatments to find one that works.
Outcome: Lifestyle changes can be effective
Many people have HS for life. Studies continue to show that making certain lifestyle changes can help tremendously. Weight loss has proven so effective that some patients say maintaining a healthy weight prevents HS breakouts.
Images used with permission of the Journal of the American Academy of Dermatology.
Aitken JF, Elwood M, Baade PD, et al. “Clinical whole-body skin examination reduces the incidence of thick melanomas.” Int J Cancer 2010 Jan 15;126(2):450-8.
Alikhan A, Lynch PJ, et al. “Hidradenitis suppurativa: A comprehensive review.” J Am Acad Dermatol 2009;60(4):539-61.
Canoui-Poitrine F, Revuz JE, Wolkenstein P, et al. ”Clinical characteristics of a series of 302 French patients with hidradenitis suppurativa, with an analysis of factors associated with disease severity J Am Acad Dermatol 2009;61(1):51-7.
Fardet L, Dupuy A, Kerob D, et al. “Infliximab for severe hidradenitis suppurativa: Transient clinical efficacy in 7 consecutive patients.” J Am Acad Dermatol 2007;56(4):624-8.
Grant A, Gonzalez T, Montgomery M, et al. “Infliximab therapy for patients with moderate to severe hidradenitis suppurativa: A randomized, double-blind, placebo-controlled crossover trial.” J Am Acad Dermatol 2010;62(2):205-17.
Habif T, Campbell J, Chapman M, et al. In: Dermatology DDxDeck. 2006.