psoriatic

Psoriatic is an adjective relating to psoriasis, a chronic autoimmune skin disease. The term is used to describe psoriasis itself and the related inflammatory conditions that can accompany it, most notably psoriatic arthritis.

Psoriasis is characterized by recurrent, well-defined red plaques with silvery scales, commonly occurring on the elbows, knees, scalp, and lower back. Nails may show pitting, onycholysis, or discoloration. The disease varies in severity and can cause itching or discomfort, with a significant impact on quality of life for some individuals.

Psoriatic arthritis is a related condition that affects the joints and periarticular tissues. It may occur with skin disease or develop later, and can present as peripheral arthritis, enthesitis, dactylitis, or axial involvement. Joint symptoms range from mild to destructive and can lead to functional impairment if not treated.

Pathophysiology involves immune dysregulation, particularly T-cell–driven inflammation with cytokines such as TNF-α, IL-17, and IL-23. Genetic predisposition plays a role, and environmental triggers such as infections, skin trauma, or stress can precipitate flares. The Koebner phenomenon, where skin injury leads to new psoriatic lesions, is sometimes observed.

Diagnosis relies on clinical assessment of skin and joint findings; biopsy is rarely needed. Management is tailored to disease extent and may include topical therapies (corticosteroids, vitamin D analogs), phototherapy, traditional systemic agents (eg, methotrexate), and biologic or targeted therapies that inhibit TNF-α, IL-17, or IL-23, as well as PDE4 inhibitors like apremilast. Effective treatment aims to control symptoms, prevent joint damage, and address comorbid conditions such as cardiovascular disease, metabolic syndrome, and depression.