[Pathogenesis of psoriasis].

Psoriasis is basically an excessive proliferation of the epiderm. This state results mainly from an imbalance in the cyclical nucleotides linked mainly to anomalies of the keratinocyte membranes. The membrane change is due to antibodies whose production may be dependent upon a deficit of a T-lymphocyte sub-population. This deficit may be considered the result of the penetration of virus agent with the help of multiple genetic factors. The various link of this pathogenic chain may be modified by numerous external factors which, by causing a worsening in a pre-existing imbalance, brings about the appearance of lesions.