What Is Hidradenitis Suppurativa?

What Is Hidradenitis Suppurativa?
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Overview

What Is Hidradenitis Suppurativa?

Hidradenitis suppurativa (HS), also called acne inversa, is a chronic inflammatory skin disease. People with HS have lesions that can include painful, deep-seated nodules and abscesses that can cause permanent scarring, says Rita O. Pichardo, MD, a dermatologist at Wake Forest Baptist Health in Winston-Salem, North Carolina. “It primarily occurs in places where skin rubs on skin, which are called intertriginous regions,” she says.

There can be periods of worsening (called flares) or improvement, but there’s usually some evidence of the condition at all times, says Dr. Pichardo.

What Is Hidradenitis Suppurativa?

Dermatologist Kristen Lo Sicco, MD, explains how and where hidradenitis suppurativa appears and how it is managed.
What Is Hidradenitis Suppurativa?

Signs and Symptoms of Hidradenitis Suppurativa

Hidradenitis suppurativa can start with an area of your skin burning, itching, or sweating more than usual.

A painful nodule can form in that area (most often in the armpit, groin area, buttocks, or inner thigh) that looks like a cyst, boil, or deep pimple.

As these bumps or nodules grow, they join together and fill up with fluid, becoming abscesses. When the mass breaks open, blood and pus is expelled. This fluid has a bad odor and can cause wet spots on clothing. The ongoing drainage that occurs with HS can be a tipoff that you have the disease. And as this process repeats, tunnels can form under the skin and cause permanent scarring.

Blackhead-like spots (often appearing in twos) can form in advanced stages. These may heal and skin may clear for a while, but then new breakouts reappear in the same area.

Hidradenitis-Suppurativa-on-Black-skin
The inflammatory pustules, boils, or abscesses of HS are bilateral, which means they occur on both sides of the body.Alamy

Causes and Risk Factors of Hidradenitis Suppurativa

The exact cause for hidradenitis suppurativa is unknown, but it’s thought to be multifactorial, says Katherine L. DeNiro, MD, a dermatologist in Wenatchee, Washington.

Risk factors include the following:

  • Genetics If you have a family member with HS, you're more likely to develop the disease.
  • Smoking Smoking seems to be a risk factor.
  • Hormonal Factors These play a role, as women are more likely to have HS than men.
  • Obesity Research links HS with being overweight as well as diseases that are related to obesity, such as diabetes and hypertension.

“That being said, there are plenty of people who develop HS and we don’t know why; they don’t have any of those risk factors. There’s still a great deal we still need to learn about what causes HS,” says Dr. DeNiro.

One thing experts know for sure, hidradenitis suppurativa is not contagious, nor is it a result of poor hygiene.

Is Hidradenitis Suppurativa an Autoimmune Disease?

The short answer is probably not. Autoimmune disease is when your immune system creates antibodies that mistakenly attack and damage your body’s healthy cells, as in rheumatoid arthritis. But in HS, the immune system becomes overactive, causing chronic inflammation. Although HS has features similar to autoimmune disease, it is usually considered an autoinflammatory condition.

Hidradenitis-Suppurativa-on-caucasian-skin
HS may be mistaken for ingrown hairs, folliculitis, or an acne-type rash.Lea Rae/Shutterstock

How Is Hidradenitis Suppurativa Diagnosed?

On average, people have HS about eight years before they are given the correct diagnosis, says DeNiro. “This includes people who are staying home and suffering in silence or have seen a provider but haven’t been correctly diagnosed yet,” she notes.

Diagnosis can be delayed for a few reasons, says Pichardo. “It can be hard to spot at first, depending on the location in the body. Some patients are embarrassed about it and reluctant to talk to anybody — their friends or family or even a healthcare professional,” she says.

Some patients and medical providers may think the HS is something else, like an ingrown hair, folliculitis, or an acne-type rash, says Pichardo. “It’s important to seek treatment early and for physicians to recognize this condition to minimize the chances of scarring and other complications,” she adds.

The first way HS is diagnosed is through the type of lesions, which are inflammatory pustules, boils, or abscesses under the skin, Pichardo says. “They are bilateral, which means on both sides of the body.”

The pustules are commonly found in certain areas of the body, although those areas are different for women and men, says Pichardo. “Usually for women these can appear under the arms, under the breasts, in the groin and pubic area, and in the inner thighs. In men, it’s mainly in the underarms, groin, and anal area.”

The most common way to assess the severity of HS is called the Hurley staging method.

Hurley Stage 1: Less Severe Disease There are isolated nodules, bumps, or abscesses with minimal or no scarring.

Hurley Stage 2 : Moderate Disease At this stage, there are widely separated nodules or abscesses that are connected to each other in what are called sinus tracts, which are like channels under the skin that connect one lesion with another and cause scarring, says Pichardo. There can be some scarring within a region of the body in this stage.

Hurley Stage 3: Severe Disease There are multiple or extensive sinus tracts, abscesses, and scarring affecting a whole area of the body at this stage.

Why Does It Take People With Hidradenitis Suppurativa So Long to Get Diagnosed?

Board-certified dermatologist Kristen Lo Sicco, MD, discusses some of the barriers to diagnosis for people living with hidradenitis suppurativa.
Why Does It Take People With Hidradenitis Suppurativa So Long to Get Diagnosed?

Treatment and Medication Options for Hidradenitis Suppurativa

There are different factors that cause HS, and because of that, treatment can be very complex, says Pichardo. “Even with treatment, our patients can flare but the goal is that these flares last a shorter time and they won’t occur as often,” she says.

The treatment plan for HS can include medication and surgery, and is determined by the type and stage of the disease, says Pichardo. “Although there is currently no ‘ideal treatment,’ the best possible outcomes are achieved when patients and their doctor work together as a team to manage HS,” she says.

Your doctor may recommend a certain type of skin cleanser as part of your daily care. Although there’s no data comparing specific agents, the use of chlorhexidine, benzoyl peroxide, and zinc pyrithione is supported by expert opinion.

Medication Options

Medication options for HS include the following:

  • Topical antibiotics such as clindamycin are often used first. These can help treat infection of the nodules, reduce inflammation, and help prevent new nodules from forming.
  • Oral (systemic) antibiotics such as tetracycline or doxycycline may be used in mild HS, and the antibiotics rifampin and clindamycin maybe used in later stages.
  • Hormonal agents such as birth control pills or spironolactone may be used in women; finasteride (Propecia) can be used in men.
  • Metformin can be used to help control flares and manage HS at any stage.
  • Topical resorcinol is a chemical peeling agent that may reduce inflammation during a flare.
  • Biologic agents may be used in severe stage 2 or stage 3 HS. Adalimumab (Humira), a tumor necrosis factor alpha inhibitor, was the first biologic agent approved to treat moderate and severe HS. Secukinumab (Cosentyx), an IL-17 inhibitor, and bimekizumab-bkzx (Bimzelx), an IL-17A and IL-17F inhibitor, are also approved to treat moderate and severe HS. Infliximab (Remicade), though not approved, has been used to reduce symptoms and inflammation.
  • Oral retinoids include acitretin (Soriatane) and isotretinoin (Accutane). These should not be used in women who are pregnant or may become pregnant.

Depending on your symptoms, your doctor may also prescribe medication for pain management, mental health, and wound care.

Surgery and Procedures

Medical procedures and surgical interventions for HS include the following:

  • Steroid injections may be used to reduce pain and inflammation in mild HS lesions during a flare.
  • Laser hair removal is sometimes used on mild HS. Reducing the amount of hair on the area affected by HS can reduce the number of nodules.
  • Deroofing is an option for people whose HS recurs in the same location on the body over and over. The skin covering a sinus tract or abscess is removed and the skin is left open to heal.
  • Wide excision is when an HS lesion, such as a tunnel, is removed. This surgery leaves a long, wide and open wound and usually reserved for more severe Hurley stage 2 or Hurley stage 3.
  • Laser surgery can be used to treat HS and drain painful bumps, but the disease must be controlled for a period of time before the procedure. It takes several months for the skin to heal from laser surgery, according to the AAD.

     Mayo Clinic notes that a carbon dioxide laser can be used for the procedure.

  • Botulinum toxin or Botox, is approved to treat excessive sweating. This can help reduce the number of infections.
  • Incision and drainage is a procedure in which a painful abscess is opened and drained. Although this may help with pain relief in the short term, it’s not considered an effective treatment for HS because the sores come back again.

Wound Care for Hidradenitis Suppurativa

Taking care of wounds caused by an HS flare or by surgery to treat HS can help prevent infection, promote healing, and reduce unpleasant odor.

Discuss wound care with your doctor because some aspects of care can be different depending on how severe the wound is, how deep it is, and whether it is wet or dry.

  • Gentle cleaners should be used to clean the skin, and the wound should be cleaned every time the dressing is changed. Avoid harsh soaps that could irritate the skin or wound.
  • Antiseptics, such as silver and iodine, are sometimes applied after cleaning to kill bacteria.
  • Antibacterial soaps and washes, like Hibiclens, contain chlorhexidine, which is used to disinfect skin and sterilize surgical instruments before surgery. But it’s gentle enough to use on skin with HS.

  • Dressing to cover the wound can help keep the wound clean and reduce the risk of infection.

Complementary and Integrative Therapies

In addition to medication and medical procedures, complementary approaches and home remedies can also help with symptoms of HS.

Dietary Recommendations There may be certain foods that can make HS worse, says Pichardo. “I recommend that my patients avoid dairy products. For example, we try to substitute cow’s milk with nondairy alternatives, such as almond milk,” she says. Brewer’s yeast may also worsen HS symptoms, research shows.

An anti-inflammatory diet that limits red meat and processed foods can be helpful in HS as well, she says.

Home Remedies Before trying any remedy, you should check in with your doctor, because recommendations may vary according to the stage of HS and whether the disease is flaring. These remedies should not replace the medications or procedures your doctor prescribes.

Pichardo does recommend a few home remedies for her patients with HS.

  • Warm Compress Place a clean washcloth under hot water and wring it out. Apply the warm compress to the affected part of the skin for 10 minutes.

  • Bleach Bath A bleach bath can decrease bacterial infection and help with symptoms. Typically, the recipe is ¼ to ½ cup common 5 percent household bleach to a bathtub full of water (40 gallons). Soak your torso or just the part of the body affected with HS for 10 minutes. Do not put your head underwater and be careful not to get the bleach or the diluted bleach bath in your eyes. Rinse off with fresh water after the bath and apply whatever moisturizer your doctor recommends.

  • Vicks VapoRub This is an over-the-counter ointment that is typically used as a cough suppressant or for sore muscles. Some people with HS report that the ointment can relieve pain when applied directly to an HS spot, but it shouldn’t be used if the lesions are draining, says Pichardo. Vicks VapoRub also has a strong menthol scent that can help overpower any smells related to HS.

  • CBD Oil Some patients have good results with CBD oil, but this is anecdotal, says Pichardo. It’s been used orally and topically.

     A review of research notes that cannabis-related products and cannabis may play a role in pain and itch relief, improved quality of life, and overall mental health in patients with HS but encourage using caution as the research is limited and dosage and formulation can vary.

  • Dietary Supplements There is evidence that low levels of zinc and vitamin D in the body are associated with increased lesion count in HS; taking supplements of zinc and vitamin D may help in reducing nodules. Before you begin taking these or any supplements, you should discuss the appropriate dosing with your healthcare team.

     There is also anecdotal evidence for taking turmeric as a supplement, says Pichardo, as it can have anti-inflammatory properties.

Prevention of Hidradenitis Suppurativa

Although there are risk factors for developing HS, it’s not clear what causes it, and so there’s no known way to prevent it.

There are ways to potentially decrease the risk of developing HS or lessen the symptoms — these include not smoking and maintaining a healthy weight.

To potentially reduce the severity of HS, wear loose-fitting clothes, take warm baths, don’t shave the affected areas of the body, and use antibacterial soap on affected areas.

Lifestyle Changes for Hidradenitis Suppurativa

For all stages of HS, lifestyle modifications are recommended. These include not smoking, and trying to achieve a healthy weight, says Pichardo. As noted above, an anti-inflammatory diet may also help with symptoms.

Hidradenitis Suppurativa Prognosis

There’s no cure for hidradenitis suppurativa at this time. It usually lasts throughout a person’s lifetime and can become more severe over time.

Because these lesions are so painful, this is a disease that negatively affects quality of life, says Pichardo. “People with HS can be embarrassed about the lesions because of the way they look and smell,” she says.

Proper treatment can manage HS symptoms and help avoid complications. In some cases HS, sores can be removed with surgery and do not return.

Research suggests that because HS is a systemic disease, patients have a reduced life expectancy.

One study found that patients had an increased risk of death from any cause, including cardiovascular or cerebrovascular causes, and that risk is particularly tied to a history of smoking.

 But getting treatment and lowering the overall burden of inflammation should, in theory, lower this risk and improve overall health.

Complications of Hidradenitis Suppurativa

If HS isn’t controlled, it can worsen and lead to complications, including the following.

Cellulitis or Sepsis Infection is relatively rare in HS, but it can happen, says DeNiro. When infection happens in the skin, it’s called cellulitis, and sepsis is when the infection is in the blood.

Damage to the Lymphatics If the inflammation is deep enough, it can injure the lymphatics, which are the vessels that carry fluid to the skin. This can cause the skin to thicken and harden and stay that way.

Injuries to Nearby Organs In severe HS in the genital area or buttock area, deep inflammation can tunnel to the bladder or bowel, which is called a fistula. A fistula is an abnormal connection between two body parts and can require antibiotics or surgery to correct.

Anemia Too much inflammation in the body can inhibit the production of red blood cells and cause anemia.

Skin Cancer In rare cases, if hidradenitis suppurativa goes untreated for years and years, it can lead to skin cancer.

Research and Statistics: Who Has Hidradenitis Suppurativa?

HS seems to be becoming more prevalent, but we’re not really sure why, says DeNiro. “It’s really been a neglected disease. It was thought to be pretty rare in the past, but now we’re learning that it’s not really that rare, it’s just that a lot of people didn’t go to the doctor about it,” she says.

An increased prevalence of HS could also be due to an increase in some of the risk factors in the population, such as obesity and diabetes, she says.

It’s estimated that about 1 in 100 people have hidradenitis suppurativa, she says.

It’s most common for people to get HS after puberty in the teen years or early twenties, but it can be diagnosed in patients as young as 9 years old or in their sixties — but those are the extremes, says Pichardo.

Women are three times more likely to get HS than men, and people who are Black or biracial are more likely to develop HS than white people.

Disparities and Inequities in Hidradenitis Suppurativa

Hidradenitis suppurativa is more prevalent in Black Americans, though we don’t know why, says DeNiro. An estimated 1.3 percent of African Americans have HS compared with 0.75 percent of white populations.

One study found that Black patients with HS had 2.8 times the odds of having Hurley stage 3 disease, 2.86 times the risk for an emergency room visit for HS, 2.25 times the risk for experiencing a hospitalization for HS, and 1.61 times the risk for needing surgery when compared with white patients.

It’s an ongoing area of research to find out if different skin colors respond to the current treatments we have in the same way, says DeNiro. “We think that they do for most therapies. In the case of laser treatments used in HS, it’s important to consider skin color when selecting what type of laser to use.” Some lasers work better on skin of color than others, she says.

There is evidence that Black Americans are underrepresented in clinical trials on HS. Although Black Americans are significantly more affected by the disease, white people make up 68 percent of study participants in HS trials. Delays in diagnosis and lack of access to specialized dermatological care also disproportionately affect Black patients.

Related Conditions of Hidradenitis Suppurativa

HS can increase the likelihood that you’ll have other health conditions.

Diabetes Although the relationship between diabetes and HS isn’t well understood, diabetes is more common in people with HS. According to a meta-analysis, people with hidradenitis suppurativa were 2.78 times more likely to have diabetes than the general population.

Polycystic Ovarian Syndrome (PCOS) A metabolic and hormonal disorder, PCOS involves symptoms like multiple cysts on the ovaries, higher than normal levels of male hormones, and irregular periods or no periods.

In a cross-sectional analysis, the prevalence of PCOS in people with hidradenitis suppurativa was 9 percent compared with just 2.9 percent in the general population.

Metabolic Syndrome This term is used to describe a group of conditions that include high blood sugar, low levels of HDL (“good” cholesterol), high levels of triglycerides, large waist circumference, and high blood pressure. A person is diagnosed with metabolic syndrome if they have 3 out of 5 of those conditions.

A meta-analysis found a significant association between HS and metabolic syndrome, even after adjusting for age, sex, other cardiovascular risk factors and medical conditions.

Arthritis Individuals with HS are three times more likely to develop inflammatory arthritis, which is a group of chronic autoimmune disorders. The risk is particularly high for developing spondyloarthritis, ankylosing spondylitis, and rheumatoid arthritis.

Depression People with HS have higher rates of anxiety and depression compared with the general population, says DeNiro. A meta-analysis found that 16.9 percent of people with HS also had depression.

Living With Hidradenitis Suppurativa

HS is a tough disease to live with, says DeNiro. “In addition to the pain and discomfort, there can be a lot of suffering with HS due to the shame and embarrassment of HS and how it impacts interpersonal relationships,” she says.

Many people don’t know a lot about the condition, or they’ve been misinformed, she says. “It’s important to know what HS is not,” says DeNiro.

HS is not contagious. “A lot of people are worried it’s like an STD or something. It’s not a sexually transmitted disease and it’s not contagious. It’s important to be aware of that,” DeNiro says.

HS is not caused by poor hygiene. “People can be told by family members or medical providers that they just need to be better at cleaning or personal hygiene and that HS would go away,” says DeNiro. That’s not true, she adds.

Being overweight doesn’t cause HS. “Being overweight is one risk factor for HS, but it doesn’t cause it. People should not feel as though they are to blame for getting hidradenitis suppurativa,” DeNiro says.

Support for Hidradenitis Suppurativa

HS Foundation

HS Foundation is a nonprofit organization dedicated to improving the lives of people with HS through advocacy, education, and resources.

HS Connect

This group helps people navigate the challenges of living with HS, providing educational resources, hosting events, and offering online support and discussion groups.

Hope for HS

An HS advocacy and awareness organization, Hope for HS offers in-person community meetups and virtual support groups across the country.

The Takeaway

Hidradenitis suppurativa is a chronic skin condition characterized by painful nodules and abscesses that can scar over time. Although there's no cure, early treatment can help with symptom management and improve quality of life. Lifestyle changes like maintaining a healthy weight and using warm compresses can be helpful strategies to alleviate flares.

Common Questions & Answers

What causes a flare-up of hidradenitis suppurativa?
HS develops when hair follicles become blocked, but what causes that blockage isn’t known. Risk factors include genetics, hormones, cigarette smoking, and obesity.
There’s no cure for HS. It can last throughout a person’s lifetime and worsen over time. But treatment can help manage symptoms, and early treatment can help alter the severity of the disease's progression.
A combination of medication, medical procedures, surgical interventions, lifestyle changes such as an anti-inflammatory diet and quitting smoking, and complementary approaches can reduce the severity of symptoms.
Warm compresses applied to affected areas can soothe skin. A bleach bath (¼ to ½ cup of bleach to a full tub of water) can decrease bacterial infection. Vicks VapoRub may relieve pain when applied to an HS spot, but don’t use it on open lesions.
Living with HS can be challenging. In addition to pain and discomfort, which can make movement difficult, HS can make you self-conscious and take a toll on your emotional health. It’s important to seek support.

Resources We Trust

Jacquelyn-Dosal-bio

Jacquelyn Dosal, MD

Medical Reviewer

Jacquelyn Dosal, MD, is a board-certified dermatologist at Skin Associates of South Florida in Coral Gables. She practices general, medical, cosmetic, and surgical dermatology.

Dr. Dosal provides compassionate care to all her patients, listening to their concerns and creating a treatment plan with each patient's priorities and real life in mind.

She is a member of the voluntary faculty at the University of Miami.

Becky Upham, MA

Becky Upham

Author

Becky Upham has been professionally involved in health and wellness for almost 20 years. She's been a race director, a recruiter for Team in Training for the Leukemia & Lymphoma Society, a salesperson for a major pharmaceutical company, a blogger for Moogfest, a communications manager for Mission Health, a fitness instructor, and a health coach.

She majored in English at the University of North Carolina and has a master's in English writing from Hollins University.

Upham enjoys teaching cycling classes, running, reading fiction, and making playlists.

EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
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