What Are the Stages of Hidradenitis Suppurativa?

Hidradenitis suppurativa, sometimes called acne inversa, is a skin condition that causes boil-like bumps under the skin. It is a chronic and painful condition that often appears in areas where skin rubs together like the groin, armpits, and genital area.

The lumps caused by the disease can break open causing abscesses that leak fluid and pus. Once the abscesses heal, there can be scarring.

Estimates suggest that hidradenitis suppurativa can impact between 0.03% and 4% of the population. Females are more likely to be affected by hidradenitis suppurativa than males. In the United States, it is believed that roughly 11 in every 100,000 people are affected by the disease.

Hidradenitis Suppurativa text

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The condition can be mild, moderate, or severe and is classified by different stages, which help healthcare providers determine the best course of treatment.

This article will review the Hurley system, used to stage hidradenitis suppurativa symptom progression, and how each stage is defined.

What Is the Hurley System?

Hidradenitis suppurativa symptoms can range from mild to severe. In 1989, a dermatologist named Hurley developed a scoring system based on the presence of wounds that have formed tunnels under the skin (sinus tracts) and scarring to diagnose the disease’s progression.

Dubbed the Hurley Stages, this system is now used to classify people with hidradenitis suppurativa into three categories based on the severity of symptoms:

  • Stage I: Mildest form of the disease, which presents with solitary pus-filled lumps (abscesses) or formations of multiple abscesses that are isolated; no sinus tracts or scarring
  • Stage II: Presents with abscesses that recur, formation of sinus tracts, single or multiple lesions that are widely spaced
  • Stage III: The most severe progression with widespread development of lesions, presenting with multiple abscesses and sinus tracts that interconnect

Statistics About HS

The exact prevalence of hidradenitis suppurativa is difficult to determine. A number of studies have attempted to establish how common the disease is using a variety of methods. As a result, the estimated prevalence of hidradenitis suppurativa ranges from between 0.03% to 4% of the population.

Studies have reported that stages I and II of the disease are the most common stages in those diagnosed with hidradenitis suppurativa.

Some studies suggest stages I and II impact between 24% and 68% of people with hidradenitis suppurativa, while other studies estimate the prevalence as between 28% and 54% of people with hidradenitis suppurativa.

It is believed that stage III of the disease is the least common, affecting between 2% and 29% of those with hidradenitis suppurativa.

Studies note, however, that these figures don’t account for the number of people living undiagnosed with hidradenitis suppurativa.

Symptoms by HS Stage

Symptoms of hidradenitis suppurativa vary based on severity and stage of the disease.

Stage I

In the earliest stage of the disease, the first symptom may be itching or discomfort in the affected area. This may be followed by the development of just one or a few bumps confined to one area of the skin.

Other symptoms may include:

  • Swelling of the skin
  • A burning sensation in the skin
  • Excessive sweating

Stage II

In the second stage of hidradenitis suppurativa, symptoms may include:

  • Single or multiple recurring lumps
  • Lumps that appear in more than one area of the skin
  • Lumps that may be bigger than those in stage I
  • Lumps that break open, causing fluid and pus to drain from the abscess, and which may be accompanied by an unpleasant smell

Stage III

In the final and most severe stage of the disease, symptoms may include:

  • Widespread lumps across multiple areas of the body
  • Chronic pain
  • Bursting abscesses
  • Difficulties with movement
  • Blackhead-like spots which may appear in pairs
  • Permanent scarring

Complications With Sinus Tracts

In many cases, especially if left untreated, a mild case of hidradenitis suppurativa will worsen, leading to the formation of sinus tracts and abscesses.

In stages II and III of the disease, sinus tracts may appear. These are tunnel-like cavities that form under the skin and can interconnect. The tunnels often cause pain and scarring.

Abscesses may also form in stages II and III of the disease. An abscess is a larger lump that holds pus. In hidradenitis suppurativa, the abscesses may join together and be very painful. They may break open and leak pus, blood, and fluid. These sores can stain clothes and also cause a foul smell.

The constant bursting-then-healing of abscesses can cause permanent scarring.

Treatment by HS Stage

Treatment is necessary to try and prevent hidradenitis suppurativa from progressing. Treatment options vary based on the stage of the disease. Treatments include medication, procedures or surgeries, skin care, and pain management.

Stage I

The mildest forms of hidradenitis suppurativa may be treated by:

  • A skincare plan, which may involve washing affected areas with a disinfectant such as benzoyl peroxide and using a more gentle antiperspirant
  • Topical prescription medications, such as antibiotic creams to treat infection or exfoliating creams to unclog hair follicles and reduce inflammation in the area
  • Corticosteroid injections, to reduce inflammation of early lumps that aren’t infected
  • Laser hair removal, to reduce the development of lumps
  • Ice packs for pain
  • Anesthetic cream, such as Lidocaine, for pain

Stage II

The second stage of the disease may require stronger treatments. These may be given if earlier treatment options have been unsuccessful. Treatment options for stage II may include:

  • Antibiotic tablets, like rifampin together with clindamycin
  • Birth control pills to regulate hormones
  • Spironolactone, a diuretic
  • An oral retinoid, like Acitretin
  • Metformin, a drug used in diabetes that can also reduce inflammation
  • Adalimumab, a biologic that helps stop the creation of pus and inflammation by the immune system, and the only FDA-approved treatment specifically for hidradenitis suppurativa
  • Medical procedures, like a Botox (botolinum toxin) injection to reduce sweating
  • Prescription pain killers

Stage III

In the most severe stage of the disease, a multi-pronged approach to treatment may be necessary. As well as the above treatment options, other treatments include:

  • IV antibiotics to treat infection and improve the likelihood of success of other treatments
  • Incision and drainage of abscesses
  • Deroofing, a medical procedure where the skin that covers an abscess or sinus tract is removed and left open to heal by itself
  • Wide excision surgery, a procedure to remove an entire tunnel or lesion
  • Laser surgery, used to vaporize hidradenitis suppurativa
  • Prescription pain killers

Tips for Living Well

Hidradenitis suppurativa can be a challenging condition, and many with the disease may experience depression. Talking with a counselor or joining a support group may help.

Other tips for living with the disease and improving symptoms include:

  • Losing weight if you are overweight
  • Quitting smoking
  • Using a warm compress or warm tea bags on painful lumps
  • Staying cool and trying to avoid excessive sweating in hot weather
  • Keeping and attending all appointments with a dermatologist
  • Wearing loose clothing and avoiding tight waistbands
  • Paying attention to other symptoms like joint pain, and consulting with a healthcare provider if you experience other issues for treatment options since those with hidradenitis suppurativa are at greater risk of other inflammatory diseases like arthritis

A Word From Verywell

Hidradenitis suppurativa is a chronic, inflammatory skin disease characterized by painful lumps on the skin. In the early stages, there may only be one or two lumps. Without treatment, the disease can progress and cause abscesses that may burst, sinus tracts that may interconnect beneath the skin, and scarring.

Fortunately, treatment options are available for symptoms of hidradenitis suppurativa. Consult your healthcare provider as soon as lumps begin to appear, as early interventions can help get the condition under control and prevent it from progressing to a more painful and serious stage.

Frequently Asked Questions

  • How do HS symptoms progress?

    Hidradenitis suppurativa can progress over time. Symptoms may begin with itching and only a few lumps, but progress to abscesses that burst and ooze pus, interconnecting tunnels deep under the skin (sinus tracts), and eventual scarring.

  • What triggers acne inversa?

    The exact cause of hidradenitis suppurativa (acne inversa) remains unknown. But researchers believe it may be related to hair follicles becoming clogged and infected with bacteria.

  • What kind of disease is HS?

    Hidradenitis suppurativa is not an autoimmune disease. It is a chronic, inflammatory skin disease that may progress in severity.

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10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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