Hidradenitis suppurativa

Hidradenitis suppurativa: This skin disease often forms on the underarm.

Hidradenitis suppurativa: Overview

Also called acne inversa

What is hidradenitis suppurativa?

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.

Some people say that their HS looks like one of these skin conditions:

Pimples
Deep-acne like cysts and blackheads
Folliculitis (looks like swollen pimple with a hair in the center)
Boils

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 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 (right).

Hidradenitis suppurativa: Signs and symptoms

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 skin. HS is most common in these areas:

Underarms (one or both)
Groin (genitals, around the anus, and surrounding area)
Buttocks
Upper thighs
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

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.
Serious infections.
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.

Images used with permission of the Journal of the American Academy of Dermatology. (J Am Acad Dermatol 2009;60:539-61.)

References:
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.
Habif T, Campbell J, Chapman M, et al. In: Dermatology DDxDeck. 2006. Mosby Elsevier. Card #35: Hidradenitis suppurativa.
Hinds, G. “Hidradenitis suppurativa: An update.” Focus session presented at the 2012 American Academy of Dermatology Summer Academy Meeting: Boston. Aug 2012.
Lavogiez C, Delaporte E, Darras-Vercambre S, et al. “Clinicopathological study of 13 cases of squamous cell carcinoma complicating hidradenitis suppurativa.” Dermatology. 2010;220(2):147-53

Hidradenitis suppurativa: Who gets and causes

Who gets hidradenitis suppurativa?

Hidradenitis suppurativa (HS) is most common in:

Overweight or obese people.
Smokers.
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.

Hidradenitis suppurativa: Diagnosis and treatment

How do dermatologists diagnose hidradenitis suppurativa?

To diagnose this skin disease, a dermatologist looks closely at the skin and asks some questions.

If your breakouts are leaking fluid, your dermatologist may swab a bit of the fluid onto a slide to find out if you have an infection. You also may need a blood test.

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.

References:
Alikhan A, Lynch PJ, Eisen DB. "Hidradenitis suppurativa: A comprehensive review." J Am Acad Dermatol 2009;60(4):539-61.
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. Mosby Elsevier. Card 35: Hidradenitis suppurativa.
Lapins J, Sartorius K, Emtestam L. “Scanner-assisted carbon dioxide laser surgery: A retrospective follow-up study of patients with hidradenitis suppurativa.” J Am Acad Dermatol 2002;47(2):280-5.
Mahmoud BH, Tierney E,. Hexse CLl, et al. ”Prospective controlled clinical and histopathologic study of hidradenitis suppurativa treated with the long-pulsed neodymium:yttrium-aluminium-garnet laser.”J Am Acad Dermatol 2010;62(3):637-45.
McMichael A, Sanchez DG, Kelly P. “Hidradenitis Suppurativa.” In: Bolognia JL, Jorizzo JL, Rapini RP, et al. editors. Dermatology 2nd ed. Spain, Mosby Elsevier; 2008. p. 528-9.
van der Zee HH, Prens EP, and Boer J. “Deroofing: A tissue-saving surgical technique for the treatment of mild to moderate hidradenitis suppurativa lesions.” J Am Acad Dermatol 2010;63(3):475-80.

Lifestyle changes can have long-lasting effects that make it easier to control your HS — or even clear HS.

Hidradenitis suppurativa: Tips for managing

If you have hidradenitis suppurativa (HS), making a few changes to your lifestyle may be the most helpful treatment of all. Dermatologists have found that patients who make some lifestyle changes tend to have fewer flare-ups. They also tend to have less severe HS.

Dermatologists offer the following tips to their patients who have HS:

Lose weight to lessen HS — or even clear your skin. If you are overweight, losing weight may be the most effective way to control HS. It may even be more effective than treatment. Dermatologists have found that when patients who have HS lose weight, they have fewer flare-ups. Losing just 10% of your body weight can make a difference.
Losing weight has additional benefits for people who have HS. Findings from one medical study showed that having HS increases the risk for developing other health problems, including heart disease and diabetes. HS also increases the risk of having a stroke. Losing weight and eating a well-balanced diet on most days can reduce these risks.
Quit smoking to reduce HS flare-ups. Quitting smoking can help you live a longer, healthier life. It also can reduce HS flare-ups and decrease the severity of HS.
Stop shaving where you have breakouts. Shaving can irritate the skin. If you want to remove the hair, ask your dermatologist what you can safely use to remove the hair.
Wear loose-fitting clothes to reduce friction. Tight waistbands and form-fitting clothes tend to rub against your skin, causing HS to flare. Wearing loose-fitting clothes, including underwear, can help.
Keep your skin cool. Overheating and sweating can cause HS to flare. If you need a product that can help reduce sweating, such as an antiperspirant, ask your dermatologist for a recommendation. Some antiperspirants are too harsh for skin affected by HS.

Immediate pain relief at home: Deep cyst or nodule

If you have a painful deep lump from HS, doing one of the following can bring quick relief:

Make tea, using a teabag. After the teabag seeps in the hot water for a minute, remove the hot teabag and place it on the painful cyst or nodule. Keep the teabag on the HS for 10 minutes.
Make a hot compress. Do this by running a clean washcloth under hot water. Place the hot compress on the HS for 10 minutes.

Dermatologists provide specific tips for each patient

These tips can help most patients who have HS. Because HS can affect the skin in different ways, other tips may help you. Your dermatologist can offer self-care tips that can help you manage your HS.

Related resources:

Clinical trials for hidradenitis suppurativa: Links to clinical trials that are federally or privately funded.
How dermatologists can help lessen the burden of hidradenitis suppurativa: Dermatologist Paul Hazen, MD, FAAD, offers his insight.

References:
Alikhan A, Lynch PJ, Eisen DB. "Hidradenitis suppurativa: A comprehensive review." J Am Acad Dermatol 2009;60(4):539-61.
Buimer MG, Wobbes T, Klinkenbijl JH. “Hidradenitis suppurativa.” Br J Surg. 2009 Apr;96(4):350-60.

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