Definition
Definition
Acanthosis nigricans is a drare ermatosis (skin disease), characterized by the presence of plaques hyperkeratotic (thick), gray or blackish skin, generally in the folds of the neck, groin, and armpits.
Symptoms
Symptoms
- Patients present, at the level of the folds, plates thick grayish coloring that will slowly darken.
- We also note the presence ofgrowths of flesh attached by a flap of skin (pendulums).
- The verrucous papillomas (wart-like lesions) on the face and hands.
- Sometimes the tongue appears to be covered with small villi.
Pathophysiology
L'acanthosis Nigricans occurs during multiple syndromes:
- Seip syndrome.
- Familial diabetes insulin resistant.
- Bloom syndrome.
- Rud syndrome.
- Costello syndrome.
- Crouzon syndrome.
- Sebaceous adenomatosis.
Medical exam
Additional examination
They will essentially highlight a primary cancer mainly at the level of the digestive tract (stomach).
Cause
Cause
There are several forms:
- La malignant form preferentially affects adults and older people. It is also called paraneoplastic and is usually associated with a stomach tumor.
- La hereditary form appears following a hyperinsulinism (excess insulin secretion) or is due to the absorption of certain medications (cortisone, nicotinic acid, estrogens, progestins) or another hormonal imbalance (syndrome of cushing, Acromegaly, syndrome of Stein-Leventhal)
- Le pseudo-acanthosis nigricans sometimes occurs in obese individuals who have dark complexions.
Treatment
Treatment
The treatment of acanthosis nigricans is that of its cause.
- The use of keratolytics sometimes gives results.
- Keratolytics are products applied to the skin, the purpose of which is to destroy excess keratin.
Evolution
Evolution
The malignant form only regresses after treatment.
In hereditary forms, acanthosis Nigricans tends to become more pronounced at puberty and then regress thereafter.
As for the drug form, it is enough to stop the treatment to obtain an improvement in the pathology.
For the shapes paraneoplastic, the evolution is dependent on the primary cancer.