Acanthosis nigricans is diffuse epidermal hyperplasia (thickening of the skin). It implies increased thickness of the Malpighian layer (stratum basale and stratum spinosum).it is a skin hyperpigmentation condition which can be characterized by areas of dark, velvety discoloration in body folds.
Acanthosis nigricans is seen in both men and women and most commonly seen in those who are overweight or have diabetes or perdiabetic condition. Acanthosis nigricans skin patches occur when epidermal skin cells begin to reproduce rapidly. This abnormal skin cell growth is most commonly triggered by high levels of insulin in the blood.
Disease statistics: In 2002-03, 0.001% (178) of hospital consultant episodes were for acanthosis nigricans in england. 100% of hospital consultant episodes for acanthosis nigricans required hospital admission and 44% of hospital consultant episodes for acanthosis nigricans were for men and 56% were women, 3% required emergency services. 51 is the mean age of occurance, 54% occured in 15-59 year olds and 15% in over 75.