Acanthosis nigricans (ah-kan-THO-sis NY-gruh-kans) is a skin condition. It causes thicker and darker patches or streaks around joints and body areas with many creases and folds (such as knuckles, armpits, elbows, knees, and the sides and back of the neck).
Some people also develop acanthosis nigricans on their palms, groin, lips, or, in very rare cases, non-crease areas like the face, back, arms, or legs. The skin may stay soft, which is why the word "velvety" is often used to describe the symptoms of acanthosis nigricans.
Acanthosis nigricans is not an infection and isn't contagious. A few kids might have mild itching, but otherwise acanthosis nigricans is harmless. Still, a doctor will run tests to rule out underlying causes that could require treatment.
Managing acanthosis nigricans means treating the conditions that are causing the skin darkening.
Sometimes acanthosis nigricans can be a warning sign of other more serious conditions, such as certain cancers and endocrine problems, along with type 2 diabetes and the health issues associated with obesity.
In rare cases, acanthosis nigricans can be caused by certain medicines, such as oral contraceptives and cholesterol medicine. In some cases, it can be hereditary (passed on to a person by his or her parents).
Usually, the only signs of acanthosis nigricans will be dark, thick, velvety patches of skin in creases and folds, usually in the neck, armpits, or groin. But it's sometimes found in the lips, palms, knuckles, soles of the feet, and other areas. In rare cases, children may have mild itching in the affected areas.
The patches of skin will usually change color slowly, over the course of months or even years. If your child's skin changes color rapidly, call your doctor right away. It could be a sign of a serious medical condition.
If your child develops acanthosis nigricans, see your doctor, who can determine whether there's a serious cause. Doctors can generally make a diagnosis of acanthosis nigricans by taking a look at the affected skin.
To test for other conditions, the doctor may order blood tests or an X-ray.
Most cases of acanthosis nigricans only involve changes in skin color and thickness, and there is no set treatment for it. For many kids, acanthosis nigricans requires no treatment at all; for some, the dark skin will eventually fade on its own.
For cases of acanthosis nigricans where an underlying cause is found, treating the cause can make the dark patches of skin fade or disappear entirely. This can mean stopping any medicine that might be causing the problem or treating any health issues.
For most kids, the best treatment for acanthosis nigricans is to maintain a healthy weight and get plenty of exercise. Encourage your child to eat a good diet and make healthy lifestyle choices. Several studies show that eating well and exercising can help lessen, and in some cases prevent or reverse, acanthosis nigricans.
Living With Acanthosis Nigricans
Acanthosis nigricans can be highly visible and hard to cover up — especially if it happens on the neck or hands. So having it it can be embarrassing for kids. They may feel self-conscious and might be teased by classmates.
To help kids feel better about their appearance, doctors often prescribe creams and lotions that can help lighten the skin. Ask as many questions as you need to in order to understand when and how to follow the treatment plan.
Don't believe the hype about bleaches, skin scrubs, and over-the-counter exfoliating treatments — these aren't likely to work and can irritate the skin, not to mention waste money.
As a parent, you can do a lot to help your child manage worry and feel less embarrassed. Talk openly about acanthosis nigricans and let your child know that he or she is not alone. Ask a doctor about local support groups or other resources that can help your child feel more confident.
Reviewed by: Patrice Hyde, MD
Date reviewed: 10/01/2016