Hidradenitis Suppurativa (HS)

What is Hidradenitis Suppurativa?

  • Hidradenitis suppurativa (HS), also known as acne inversa (AI), is a common, painful, debilitating, and chronic inflammatory skin disease affecting 1-4% of the global population, primarily occurring in the crease areas of the skin, e. g. axillae (armpits) and groin.
  • HS usually produces painful and chronically recurring, deep-seated follicular papules and pustules.
  • They may enlarge to become nodules, may form abscesses that discharge foul-smelling pus, leading to nodular scars and distortion of the skin.
  • The tendency of the process to cause tunnels ultimately leads to inter-connected sinuses and attempts to heal these leads to thickened scars.

What are the causes of Hidradenitis Suppurativa?

The search for the cause of HS has been difficult. Suggested causes include:

  • Hormones/hormone imbalance
  • Local factors including heat and humidity, sweating, rubbing of skin-to-skin
  • A reaction to deodorants or other topical chemicals
  • Abnormal inflammatory responses to follicle rupture
  • Abnormal responses to normal bacteria in the skin
  • Abnormal healing responses to follicular injury
  • Diet
  • Heredity, and
  • Abnormal control of growth factors within the follicle/pore.

Ratio: F:M is 3:1


Manifestations of HS

Local Lesions:

  • Individual lesions may consist of inflammatory bumps, similar to pimples, usually occurring in the creases: the underarms, groin, under breasts, and between buttocks. Small pimple-like lesions may progress to become nodules, pustules, or soft tender reddish-purple masses that look like boils.
  • With repeated inflammation and scarring, there may develop sinus tracts, inter-connected tunnels under the skin where pressure on one area may express pus from a pore distant from the original point of pressure. Lesions are typically painful, and may drain a foul-smelling material. Large amounts of pus are common, and may lead to staining of clothing, lesions will fill with a gelatinous substance and extend further under the skin, especially in pressure areas. These look like a large boil but are purplish-red instead of hot red, are broad-based instead of localized, and do not ‘point to the surface and rupture and discharge and heal like a true infected boil.
  • Although early lesions may come and go, these gel-filled cavities, the tunnels, and the scars that develop will often persist for months or years. Similarly, drainage and/or pain may occur intermittently, or be continuous.

Other Associations:

  • Other body inflammations may occur. HS may be seen in some patients with inflammatory bowel disease, and especially Crohn disease.
  • In other patients, rheumatoid arthritis-like joint aching may occur. Additionally, several other rare inflammatory conditions of the skin – Sweet’s syndrome, Behçet’s disease, or Pyoderma Gangrenosum – may be seen with HS.
  • The metabolic syndrome, with its tendencies toward diabetes; or hormone imbalances such as polycystic ovaries, are often found in patients with HS.

Impact on Patients

  • HS is recognized to be significant in interfering with social interaction, job performance and attendance, and intimate relationships. Hidradenitis causes pain, itching, drainage, odor, and scarring, and may lead to marked embarrassment. There is, therefore, frequently significant emotional impact on patients and their families
  • Our skin is the most visible part of our body. It is important for our interpersonal relationships, self esteem and self image. Hidradenitis suppurativa causes painful malodorous sinuses, swollen abscesses and disfiguring scarring with unpredictable drainage that results in debilitating depression and embarrassment. For women starting with painful draining nodules at puberty or in their early teens, it ruins their confidence, resulting not only in depression but self destructive behavior. This is often made worse by inadequate or poor care.

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.

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.


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.