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 India the prevalence rate for Acanthosis nigricans was noticed that the flexural involvement (flexures of groins, knees and elbows) was seen in 40% patients, lip involvement was seen in 6.6% patients, and dorsal involvement was seen in 3.3% patients each. Increased serum testosterone levels were seen in 13.3% patients and increased DHEAS levels were seen in 20% patients. Regarding the types of AN, obesity induced AN or pseudo-AN was seen 70% patients.