Overview of Hidradenitis Suppurativa
Hidradenitis suppurativa, also known as acne inversa, is a chronic, noncontagious, inflammatory condition characterized by pimple-like bumps or boils and tunnels or tracts on 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.
Who Gets Hidradenitis Suppurativa?
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 seem to increase the risk of developing HS. People who are obese tend to have more severe symptoms. The disease cannot be spread from one person to another. Poor personal hygiene does not cause HS.
Symptoms of Hidradenitis Suppurativa
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 tracts, narrow tunnel-like structures beneath the skin. In some cases, HS leaves open wounds that won’t heal. The disease 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 frequent sites of lesions may include 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 will be affected as well.
Causes of Hidradenitis Suppurativa
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.