Psoriasis is a chronic, autoimmune, inflammatory, sometimes disfiguring, skin and joints disease, which has a high impact on health-related quality of life. Epidemiological studies from around the world have estimated the prevalence of psoriasis to be 0.6% to 4.8% [176]. Current evidence suggests that psoriasis is caused by the interaction of genetic-environmental factors and the immune system [177-179].
