What is psoriasis?
Psoriasis is a common, chronic, relapsing, immune-mediated, inflammatory disorder with primary involvement of the skin and a strong genetic predisposition. The disease onset usually occurs in younger ages. Skin lesions typically represent erythematous, inflammatory plaques and silvery scaling expressing the inflammatory changes and keratinocyte hyperproliferation.
A substantial proportion of psoriasis patients experience an inflammatory polyarthritis (psoriatic arthritis) that may include enthesitis, synovitis, tenosynovitis, periostitis, osteitis, sacroiliitis and spondyloarthritis. Psoriasis and psoriatic arthritis cause major physical, functional and psychosocial disability.
With increasing severity the spectrum of psoriasis is associated with signs of systemic inflammation and several comorbidities including cardio-vascular diseases, the metabolic syndrome, an increased risk for mortality and shorter life-span. Special types include nail psoriasis, pustular psoriasis (localized to palms and soles, or generalized), psoriatic erythroderma, inverse psoriasis and various forms of palmo-plantar involvement.
