Acanthosis nigricans can be a sign of other medical conditions, so it’s important to bring it up with your healthcare provider.
Acanthosis Nigricans Symptoms
With acanthosis nigricans, dark, thickened, velvety skin slowly develops in areas of the body where there are skin folds, typically the armpits, underarms, groin, and the fold of the neck.
The pigmentation may also appear over the joints in the fingers and toes. The affected skin stays soft and doesn’t toughen.
Some people call the line on the neck the sugar line or sugar necklace (due to its association with diabetes). Less often, the pigmentation appears on the lips, palms, or soles of the feet, which is associated with cancer.
Causes
Acanthosis nigricans can affect otherwise healthy people, and it is not always related to a medical condition.
However, it is associated with these conditions:
Obesity: This is the most common association. Losing weight can reverse it Genetic disorders: Down syndrome can cause it. Cancers of the digestive tract, liver, kidney, bladder, or lymphoma: This is rare. Polycystic ovary syndrome (PCOS) and ovarian cysts; PCOS is associated with insulin resistance and diabetes. Medications: This includes birth control pills, human growth hormone, high-dose niacin, prednisone, and some other medications. Type 2 diabetes: One 2016 study noted that more than half of children with type 2 diabetes have acanthosis nigricans. Adults with diabetes often develop it as well.
Diagnosis
Discuss your skin changes with your healthcare provider, who will examine your skin and can usually diagnose it based on its appearance.
Insulin causes glucose to be taken into the body cells to be used for energy. Someone with insulin resistance will require larger amounts of insulin for glucose is taken into the body tissues.
Your practitioner may order blood sugar levels or insulin levels. In some cases, endoscopy or X-rays are needed to check for cancer and other causes.
Treatment
Primary treatment of acanthosis nigricans aims to correct the underlying cause. It is reversible and will disappear as the cause is treated. Weight loss and reversing insulin resistance are the most effective ways to eliminate the skin changes.
Topical retinoids increase the shedding of normal skin cells, which can reduce the appearance of the lesions.
There are also cosmetic treatment options if acanthosis nigricans is severe or does not improve with weight loss. Treatments include laser therapy, topical retinoids, and dermabrasion. These procedures should only be performed by a certified dermatologist.
Its exact cause is unknown, but it is associated with obesity, polycystic ovary syndrome, type 2 diabetes, genetic disorders, and certain cancers. You can also have acanthosis nigricans without any other medical conditions.
