Acanthosis nigricans is a condition characterized by dark, thick areas on the skin. The areas affected are spread out, and the skin is velvety. It is most common in the armpits and other body folds.
There are at least four disease processes associated with acanthosis nigricans: Gougerot-Carteaud syndrome occurs in young females and is probably inherited.Malignant acanthosis nigricans is sometimes seen in adults with cancer of the genital, urinary, or gastrointestinal systems.Miescher syndrome is an inherited disease that causes skin lesions for no apparent reason.Pseudoacanthosis nigricans is caused by a hormone imbalance in the body that may cause excess insulin in the blood.
Acanthosis nigricans causes skin lesions that are darker than the skin around them. The lesions have a velvety feel. The lesions often form in the folds along the neck, armpits, groin, knuckles, between the legs, at the elbow, under the breasts, and around the belly button.
There are many causes of acanthosis nigricans, including: Addison disease, which is caused by a deficiency of hormones from the adrenal glanddiabetesdisorders of the pituitary gland within the braingenetic causesgrowth hormone therapyhypothyroidism, which means low levels of thyroid hormone that are caused by decreased activity of the thyroid glandinsulin resistance caused by obesityoral contraceptivessome medicines, such as nicotinic acid, which are used to treat high cholesterol
When acanthosis nigricans is caused by obesity, weight management is key. When it is caused by cancer, there may be little that can be done to prevent it until the cancer is successfully treated. Acanthosis nigricans caused by medicine may go away once the medicine is stopped.
A healthcare professional can diagnose acanthosis nigricans by doing a medical history and physical exam.
A person with acanthosis nigricans may have chafing of the skin. These areas do not become cancerous. The appearance of these chafed spots bothers some people.
Acanthosis nigricans is not contagious and poses no risk to others.
Treatments of acanthosis nigricans include the following: antibiotic ointments or creamsretinoids, taken orally or used in a creamtopical corticosteroid creamsweight loss to lower insulin resistance
Side effects of steroid creams and ointments include stretch marks and thinning of the skin. Retinoids can cause birth defects if taken by a pregnant woman.
The healthcare professional may recommend treatment for an underlying condition or disease. For example, obese people may be advised to lose weight to lower their insulin resistance. A person who has diabetes will need to keep blood glucose levels under good control.
The disease or condition that is causing acanthosis nigricans will need to be monitored. Any new or worsening symptoms should be reported to the healthcare professional.