Acanthosis nigricans

What is acanthosis nigricans?

Acanthosis nigricans (ay-can-THOE-sis NIE-gri-cans) (AN)
is a skin condition that causes one or more areas of skin to darken and thicken. The affected skin often feels velvety.

People who get this skin condition sometimes mistakenly believe that a dye or something else they touched has discolored their skin. Vigorous scrubbing will not get rid of the darkened skin.

Acanthosis nigricans is not contagious. It is not harmful. Sometimes, it is a warning sign of a health problem that requires medical attention. For this reason, it is important to see a dermatologist if you notice an area of darker, thicker skin.
A dark crease on the back of your neck or darker skin in your armpit could be acanthosis nigricans.

When to see a dermatologist

If you notice a change to your skin, you should see a dermatologist. Small changes may seem like nothing. Sometimes a small change is an early warning sign. AN can be a sign of pre-diabetes, which increases your risk of getting diabetes. Making lifestyle changes before diabetes develops can prevent diabetes.

Some people get AN from a medicine that they are taking. Changing medicines might be an option for you. Other times, these dark patches have no connection to any medical condition. A dermatologist can help you find out what’s causing your skin changes.

Source: https://www.aad.org

Signs, symptoms

This skin condition causes some easily recognized signs and symptoms. You may notice:

• Brown or black discoloration on your skin.
• Affected skin may feel velvety and thicker than the surrounding skin.
• Skin tags may form on the darkened skin.
• Skin can itch.
• Skin can have a bad odor.

Where acanthosis nigricans forms

A velvety, dark patch of skin can form on most areas on the body, including the:

• Armpits.
• Back of the neck.
• Groin area (especially in skin folds and creases).
• Elbows.
• Knees.
• Knuckles.
• Belly button.
• Woman’s breasts (beneath).
• Face.
• Female genitalia.

Less often, a patch can form on the lips, mouth, eyelids, palms of the hands, bottoms of the feet, and nipples.

Acanthosis nigricans (AN) tends to appear slowly, taking months or years to form. If it appears suddenly, you should immediately make an appointment to see a dermatologist. When AN appears suddenly, it can be a warning sign of cancer.

Source: https://www.aad.org

Who gets, causes

Who gets acanthosis nigricans?

Anyone can get this skin condition. Some people, however, have a greater risk. People who are most likely to get acanthosis nigricans (AN) are:

• Obese or overweight.
• Of Native American, African, Caribbean, or Hispanic descent.
• From a family with a history of AN.

Acanthosis nigricans is most common in people who are obese or have diabetes.

What causes acanthosis nigricans?

People get this skin condition for many reasons. Obesity is the most common cause. Studies show that when obese children and adults who have AN lose a significant amount of weight, they often see their skin clear.

People who are completely healthy also get AN. These people tend to have others in their family with this skin condition.

Sometimes, AN is a warning sign of something going on inside the body. It can warn about:

• Pre-diabetes or diabetes: If you have pre-diabetes, making some lifestyle changes can help prevent diabetes. If you have diabetes, it is important to find out so that you can treat it.
• A reaction to a medicine: Birth control pills, strong corticosteroids like prednisone, and niacin can cause AN.
• Hormonal disease: This skin condition can be a sign of polycystic ovarian syndrome (PCOS), thyroid disease, or a problem with the adrenal glands.
• Cancer: When AN develops quickly, it can be a sign of a cancer, especially a cancer in the stomach, colon, or liver.

Source: https://www.aad.org