Acanthosis nigricans
is a skin disorder
that usually occurs
in body folds,
such as the posterior and lateral folds of the neck, the axilla, groin, umbilicus, forehead, and other areas.
Acanthosis nigricans
is described as a
brown to black, poorly defined, velvety hyperpigmentation of the skin.
The lesions are asymptomatic but resemble dirty areas of the skin but cannot be scrubbed off.
Pictures of
acanthosis nigricans
are available on-line (see References, below).
Acanthosis nigricans
frequently occurs in people with type 2 diabetes,
or in people with a family history of diabetes.
It may precede the diagnosis of diabetes,
thereby alerting the physician to screen for the
possibility of diabetes.
The exact cause of NLD is unknown, but it is clearly associated with insulin resistance.
In older adults,
acanthosis nigricans
may be associated with malignancies rather than diabetes.
Treatment of acanthosis nigricans is difficult.
Patients without known diabetes should be screened
for diabetes; tight control of glucose levels
may result in improvement.
Older patients should be screened for cancer.
References
1.
Acanthosis Nigricans
A 9+ minute video at Medicana Life.
2.
Acanthosis Nigricans
From the
American Osteopathic College of Dermatology.
With pictures.
3.
Acanthosis nigricans
At
Wikipedia.
With one picture (reproduced here).
4.
Acanthosis Nigricans
At Skinsight.
With pictures.
