We are still unsure as to what precisely causes psoriasis. Nevertheless, we know that outbreaks of psoriasis may be triggered in individuals who have a genetic predisposition to the disease, when confronted with several factors:
- a psychological shock
- clothing that rubs against the skin
- particular medicines
- an infection (rhinopharyngitis, pharyngitis...)
Psoriasis is, in fact, caused by chronic inflammation. This inflammation, confirmed by the presence of T lymphocytes, speeds up the cellular renewal process. This accelerates the production of keratinocytes, which are epidermal cells. Rather than the normal 28-day renewal process, these keratinocytes take only 3 or 4 days to go from the basal layer to the epidermal stratum corneum. The cells remain on the skin’s surface and begin to accumulate. This causes red scaly patches to form. Although these psoriatic plaques may sometimes be inconspicuous, at other times they can be much more visible and thus a handicap for the afflicted individual.