Hidradenitis suppurativa (HS) is a chronic skin disease. It causes painful, boil-like bumps that form under the skin. It often affects the areas where your armpits and groin are cleaned with the skin. The bumps become inflamed and painful. They often open and cause lumps that drain fluid and pus. As the bumps heal, they can cause skin scarring.

This often leads to the trapping of sweat and bacteria in the surrounding tissue, causing inflammation and infection. HS is very painful and debilitating, but it is rarely fatal; Bacterial infection in a person with a weakened immune system occurs only when it leads to excessive systemic infection.

Alternate name

• Acne Inversa

Who gets hidradenitis suppurativa?

Hidradenitis suppurativa affects between 1 to 4 percent of people in the US. It is more common in female than in male. Hidradenitis suppurative usually appears in adolescents, from puberty (approximately 11 years) to 40 years. It is also more common in African Americans, smokers, and people who are overweight or obese.

Causes of hidradenitis suppurativa

HS is caused by plugging the opening of the sweat gland (apocrine duct) in the hair follicles. There may also be a bacterial infection. The causes include:

• Acne
• Diabetes
• Heart disease
• Dissecting cellulitis (severe patchy hair loss on the scalp)
• Inflammatory bowel diseases (some, like Crohn’s, have skin symptoms that mimic hidradenitis suppurativa)
• Polycystic ovarian syndrome (a hormonal disorder in women)
• High body mass index (being overweight)

Risk factors

Risk factors that may increase your chances of developing HS include:

• Being a woman
• Taking certain medications
• Having overweight or obesity
• Having a family history of HS
• Being between the ages of 20 and 39
• Having severe acne, arthritis, Crohn’s disease, IBD, metabolic syndrome, or diabetes
• Being a current or past smoker
• Being of African descent
• Having a lower socioeconomic status

If you have HS, it is important to get tested for other conditions:

• Diabetes
• Depression
• Skin cancer

You may be at higher risk for these.

Symptoms of hidradenitis suppurativa

People with hidradenitis suppurativa may first develop small bumps, sores, or boils on the skin.

Unlike normal acne, these sores are often recurrent, affect both sides of the body, and develop in areas where the skin experiences folds or friction. These areas include the:

• Groin
• Underarms
• Upper thighs
• Breasts
• Buttocks
• Folds under the stomach

Although rare, some studies have found HS near the ear or around the belly button. There have also been some cases where HS has appeared on the face, neck, or back.

Women have breakouts on the genitals and upper thighs. Men have HS in the genitals and around the anus.

For some, the lesions develop in the same place each time, but for others, they appear elsewhere. Hidradenitis suppurativa is a lifelong condition.

Diagnosis of hidradenitis suppurativa

Your doctor will examine your skin and make a diagnosis based on where the bumps and bags are and how often you have them.

They can also ask questions like you:

• How long ago did your symptoms start?
• Are they painful?
• Have you had these symptoms before?
• Does anyone close relative have this problem?

You should not have tests unless your doctor needs to rule out other types of infections. Then they take a sample of the pus and send it to the lab for analysis.

Stages
HS is divided into three stages, called Hurley stages based on their severity.

• Hurley stage I: Stage I HS involves the formation of a sinus tract (narrow openings under the skin) or an isolated lesion or tumors without scars.
• Hurley stage II: More than one bump but little tunneling
• Hurley stage III: Stage III HS involves multiple lesions with sinus tract structures, scars, and sometimes foul-smelling pus in one area of the body.

Treatment
There are several treatment options for hidradenitis suppurativa, including prescription drugs and surgery for severe cases. Therapies can help reduce or eliminate existing flare-ups, prevent new flare-ups, and eliminate scars and fistulas.

Medications

• Antibiotics: These medications can reduce inflammation, fight infection, keep HS from getting worse, and stop new flare-ups.
• Biologics: These drugs work by suppressing the immune system. This is an injection that you give yourself. Other biology requires infusion in a hospital or clinic. Some patients have been seen clearing up their HS for a long time with biologics.
• Corticosteroids: Your dermatologist may inject corticosteroids directly into the painful cyst or prescribe corticosteroid tablets. They both reduce inflammation, which can help eliminate HS and prevent new flare-ups.
• Hormones: Some women with HS relieve pain and symptoms by taking birth control pills, a medicine called spironolactone, or another hormone-regulating medicine. These medications reduce pain and allow fluid to drain out of the flare.

Surgery

Hidradenitis suppurativa surgery is performed under general anesthesia. You will be sleepy and comfortable throughout the entire surgical procedure. Surgical removal of the affected areas (excision) and, most often, covering this area with a flap (taking loose skin from another area) or a skin graft. Those with an active infection or tumor should receive treatment to resolve the active infection before definitive surgical treatment.

Complications

Untreated or severe HS can have complications over time, including:

• A general feeling of being unwell and tired (malaise).
• Depression
• Long-term (chronic) infection leading to problems such as anemia, kidney problems, and low levels of protein in the blood.
• Joint pains and inflammation (arthropathy)
• Skin cancer: It is a very rare but very serious chronic hidradenitis suppurative.
• Fistula formation: A fistula forms (which is very rare) when channels, called the sinus tract, tunnel to other parts of the body, such as the intestines or bladder.

Departments to consult for this condition

• Department of dermatology