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Acanthosis Nigricans

Definition

Acanthosis nigricans is a skin condition in which brown or black velvet-like markings appear under the arms, in the groin, or on the back of the neck. Any skin fold can be affected, including the lower lip and chin.

Causes

Causes of acanthosis nigricans may include:

Risk Factors

Acanthosis nigricans is more common in people of African-American decent. Other factors that may increase your chance of acanthosis nigricans include:

Symptoms

Symptoms include velvety-looking, dark areas anywhere on the skin.

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done.
Tests may include:
Your bodily structures may need to be viewed. This can be done with:
Endoscopy
Endoscope in stomach
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Treatment

Treatment often involves treating the underlying cause. For example, if acanthosis nigricans is due to obesity, weight loss can improve the skin condition.
Topical and oral retinoids and other medications have been reported to improve appearance in some cases. They help remove excess layers of skin.

Prevention

To reduce your chances of acanthosis nigricans:

RESOURCES

American Academy of Dermatology http://www.aad.org

NORD—National Organization for Rare Diseases http://www.rarediseases.org

CANADIAN RESOURCES

Canadian Dermatology Association http://www.dermatology.ca

Health Canada http://www.hc-sc.gc.ca

References

Acanthosis nigricans. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated July 11, 2014. Accessed September 2, 2015.

Clark N, Stulberg DL, Tovey D. Common hyperpigmentation disorders in adults: part II. Melanoma, seborrheic keratoses, acanthosis nigricans, melasma, diabetic dermopathy, tinea versicolor, and postinflammatory hyperpigmentation. Am Fam Physician. 2003;68(10):1963-1968.

Katz AS, Goff DC, Feldman SR. Acanthosis nigricans in obese patients: presentations and implications for prevention of atherosclerotis vascular disease. Dermatol Online J. 2000;6(1):1.

Kong AS, Williams RL, Rhyne R, et al. Acanthosis Nigricans: high prevalence and association with diabetes in a practice-based research network consortium—a PRImary care Multi-Ethnic network (PRIME Net) study. J Am Board Fam Med. 2010;23(4):476-485.

Luba MC, Bangs SA, Mohler AM, Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;67(4):729-738.

10/15/2010 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Kong AS, Williams RL, Smith M, et al. Acanthosis nigricans and diabetes risk factors: prevalence in young persons seen in southwestern US primary care practices. Ann Fam Med. 2007;5(3):202-208.

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