WHAT IS ACANTHOSIS NIGRICANS?Acanthosis nigricans is a darkening and thickening of the skin. The skin feels velvety and is discolored brown to grayish-brown. It is most commonly found on the neck, armpits, groin, and other skin folds. It is more common in darker skin tones and is primarily seen in overweight or diabetic individuals. It is a harmless condition, but cosmetically disturbing. It usually causes no symptoms. Sometimes it is itchy. It can have an unpleasant odor, especially if the skin is very thick and bacteria accumulate in the folds. Acanthosis nigricans occurs equally in men and women and can begin at any age, but usually after puberty.
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| acanthosis nigricans |
acanthosis nigricans |
acanthosis nigricans |
The skin lesions are symmetrically distributed over the body. Sometimes, stalked warts are also present in the acanthosis nigricans areas. These are called skin tags, acrochordons, or fibroma molle. They are small, soft, skin-colored, spherical, or stalked warts.
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| stalked warts |
stalked warts |
stalked warts |
HOW DOES ACANTHOSIS NIGRICANS OCCUR?It is believed that skin cells and pigment cells grow under the influence of hormonal changes that occur with obesity and diabetes. Skin cells can be stimulated to grow by growth factors such as insulin-like growth factor (IGF). These growth factors circulate in the blood at elevated levels in people who are overweight and in diseases such as diabetes, metabolic disorders, polycystic ovary syndrome, Cushing's syndrome, acromegaly, metabolic syndrome, and hereditary conditions. Acanthosis nigricans can be hereditary. Acanthosis nigricans can also be caused by medications (usually hormone treatments).HOW IS THE DIAGNOSIS MADE?The diagnosis of acanthosis nigricans is based on the clinical picture, its appearance. It's a fairly typical condition, and further testing is rarely necessary. Blood glucose levels can be measured if this has never been done before.HOW IS ACANTHOSIS NIGRICANS TREATED?Because acanthosis nigricans is a benign condition with few symptoms, treatment is usually unnecessary. Sometimes, for cosmetic reasons, the doctor may ask if something can be done about it. One option is to address the underlying cause. If you are overweight, this means trying to lose weight (this may resolve the abnormalities). In diabetes, glucose levels should be properly regulated. If the condition is caused by medication, discontinue or replace it (if possible).
The stalked warts can be clipped off under local anesthesia or treated with electrocoagulation.
The thickened and darkened skin can be treated with topical creams such as vitamin A (tretinoin) cream. This improves the skin's structure and has a mild abrasive effect. It can also cause irritation, in which case it is counterproductive, especially in darker skin, which can react to irritation by darkening.
Another cream that can be used is calcipotriol cream. Calcipotriol is a vitamin D-derived substance that inhibits epidermal cell division.
For significantly thickened skin, you can try scraping off the top layer with a dermabrasion device or removing it with a laser (CO2 laser). This can, however, cause discoloration and scarring.
Scrubbing and abrading the skin is usually counterproductive, and will only cause the skin to thicken over time.WHAT IS THE PROSPECT FOR ACANTHOSIS NIGRICANS?Acanthosis nigricans is a chronic skin condition that usually doesn't go away on its own and is difficult to treat. If the underlying cause can be addressed, for example, by losing weight, the condition may disappear. Acanthosis nigricans causes few symptoms. It can be cosmetically disturbing, however. Sometimes it's a symptom of an underlying disease. |
