Hidradenitis Suppurativa (HS)

Definition

Hidradenitis suppurativa, also known as HS and less commonly as acne inversa, is a chronic, noncontagious, inflammatory condition characterized by painful bumps or boils and tunnels in and under the skin. Pus-filled bumps on the skin or hard bumps beneath the skin can progress to painful, inflamed areas (also called “lesions”) with chronic drainage.

HS starts in the hair follicle in the skin. In most cases, the cause of the disease is unknown, although a combination of genetic, hormonal, and environmental factors likely play a role in its development. The disease can significantly affect a person’s quality of life.

Risk Factors

Hidradenitis suppurativa affects an estimated three women for every man and is more common in African Americans than in whites. HS often appears around puberty.

Having a family member with the disease increases the risk of developing HS. An estimated one-third of people with HS have a relative with the condition.

Smoking and obesity may be linked to HS. People who are obese tend to have more severe symptoms. HS is not contagious. Poor personal hygiene does not cause HS.

Causes

Hidradenitis suppurativa begins in the hair follicle in the skin. The cause of the disease is unknown, although a combination of genetic, hormonal, and environmental factors likely play a role in its development.

An estimated one-third of people with HS have a family member with a history of the disease. The disease seems to have an autosomal dominant pattern of inheritance in some affected families. This means that only one copy of an altered gene in each cell is needed to cause the disorder. A parent who carries the altered gene has a 50 percent chance of having a child with the mutation. Researchers are working to identify which genes are involved.

Symptoms

In people with hidradenitis suppurativa, pus-filled bumps on the skin or hard bumps beneath the skin can progress to painful, inflamed areas (also called “lesions”) with chronic drainage. In severe cases, the lesions can become large and connected by narrow tunnel-like structures beneath the skin. In some cases, HS leaves open wounds that won’t heal. HS can cause significant scarring.

HS tends to occur where two areas of skin may touch or rub together, most commonly the armpits and the groin. Lesions may also form around the anus, on the buttocks or upper thighs, or under the breasts. Other less frequently involved areas may include behind the ear, the nape of the neck, the areola of the breast, the scalp, and the area around the navel.

Some people with relatively mild disease may have just one affected area, while others have more extensive disease with lesions in multiple sites. Skin problems from HS are usually symmetrical, meaning if an area on one side of the body is affected, the corresponding area on the opposite side is often affected as well.

Diagnosis

Early diagnosis and treatment of hidradenitis suppurativa is important both for managing symptoms and reducing the development of new lesions. Doctors can often diagnose the condition by examining the skin for boils in locations that are characteristic for the disease. Laboratory tests of fluid from the lumps and blood tests may occasionally be performed to rule out other diagnoses.

Treatment

Treatment for hidradenitis suppurativa is individualized and targeted at reducing the skin lesions and preventing the progression of the disease. Options will vary depending on several factors, including the severity and extent of the lesions and possible complications.

A TNF inhibitor, from a class of medications known as “biologics,” is approved for the treatment of moderate to severe HS. Other medications used in the management of HS include antibiotics, corticosteroids, immunosuppressants, retinoids, hormone therapy, and approved treatments for other medical conditions. Laser hair removal may also prove beneficial. Some patients take medications to manage pain associated with the disease. Surgical techniques can help, such as de-roofing (taking the tops off) of lesions, and wide excision of the affected area in more advanced cases.

Treatment will often begin with a primary care clinician; however, primary care clinicians often refer patients to dermatologists, particularly in cases of more severe or hard-to-treat disease.

Psychological counseling may be helpful for people dealing with the emotional effects of the disease.

Health care professionals such as a family doctor, internist, or pediatrician treat hidradenitis suppurativa. Depending on your symptoms, your primary care doctor may refer you to a dermatologist, a specialist who is trained to diagnose and treat diseases of the skin.

Living with HS

In addition to treatment prescribed by a doctor, people can do several things on their own to be more comfortable and, in some cases, minimize lesions. These include: