Causes of psoriasis

Psoriasis is an autoimmune disease that disrupts the normal skin cell growth cycle by increasing the turnover rate in skin cells and shortening the cell cycle. Psoriasis is likely caused by a combination of genetics and environmental triggers. One third of psoriasis patients have a direct relative with psoriasis. Immune cells affect the skin by releasing growth factors that over stimulate skin cells. These growth factors cause the skin to grow too quickly, which results in a buildup of dead skin layers and forms the silver scaly patches of skin. The dilation of nearby blood vessels is the cause of redness and inflammation of the skin.

Psoriasis is sometimes, but not always, linked to certain irritants that trigger a psoriasis flare-up. Psychological stress and certain medications have been implicated in triggering psoriasis lesions in some patients.