Hidradenitis Suppurativa

This skin disease often forms on the underarm.

What is hidradenitis suppurativa?

Hidradenitis suppurativa (HS) is a disease that usually begins as pimple-like bumps on the skin. The pimple-like bumps tend to develop in places that everyday pimples do not appear. HS is most common on the underarms and groin.

Getting treatment for HS is important. Early diagnosis and treatment can prevent HS from worsening.

If HS worsens, the pimple-like bumps can grow deep into the skin and become painful. They can rupture, leaking bloodstained pus onto clothing. This fluid often has a foul odor.

As the deep bumps heal, scars can form. Some people develop tunnel-like tracts under their skin. As the skin continues to heal and scar, the scars thicken. When thick scars form in the underarm, moving the arm can be difficult. Thick scars in the groin area can make walking difficult.

Because HS can look a lot like acne, folliculitis, or boils, it is best to see a dermatologist for a diagnosis. To a dermatologist’s trained eye, the differences between HS and other skin diseases are subtle but obvious. Proper treatment depends on an accurate diagnosis. Hidradenitis suppurativa: In its earliest stage, HS often looks like boils or pimples (left), but with time thick scars can form.

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Frequently Asked Questions

How do dermatologists diagnose hidradenitis suppurativa?

To diagnose this skin disease, a dermatologist looks closely at the skin and asks some questions.

If your breakouts are leaking fluid, your dermatologist may swab a bit of the fluid onto a slide to find out if you have an infection. You also may need a blood test.