La seborrheic dermatitis designates a skin disease benign which is characterized by formation of red patches accompanied by squames, kinds of dandruff on the surface of the skin. This illness evolves in spurts and can last for several years.

It is said to be “seborrheic” because it mainly affects oily parts of the skin, such as the face, trunk and hair. It has no character of gravity and does not cause any complications but is aesthetically embarrassing. The proliferation of yeast would be responsible for the red patches. The treatments are based on the use ofantimycosiques (shampoos, creams, lotions).

It relates to between 3% and 5% of the population and is manifested by the creation of red patches and scales of white or yellowish coloring.

The causes of seborrheic dermatitis

At present, the origin of seborrheic dermatitis is not known with certainty.

Two elements are involved: the oily skin area and a fungus (yeast) Type Malassezia furfur (formerly pitysporum). But it does not appear that sufferers suffer from excess sebum production.  Malassezia-type yeasts are present on all skin types, but some people seem to react to them inappropriately, possibly leading to seborrheic dermatitis. Another hypothesis is that the yeasts convert the sebum into free fatty acids, which themselves are the source of inflammation.

Diagnostic

The visible manifestations are sufficient for the doctor to make a diagnosis, although the lesions presented sometimes resemble those of the Psoriasis. It is not always easy to differentiate between these two diseases. We also speak of sebopsoriasis in the profuse forms of seborrheic dermatitis associated with psoriasis plaques on the body.