Psoriatic arthritis for dermatologists.

Psoriatic arthritis (PsA) affects up to one-third of patients with psoriasis. It is the major comorbidity of psoriasis because of the likelihood that loss of function and permanent disability will develop if initiation of treatment is delayed. Dermatologists are uniquely positioned to recognize early signs of PsA and be the first-line healthcare practitioners to detect PsA in patients with psoriasis. PsA can affect six clinical domains: peripheral arthritis, dactylitis, enthesitis, psoriasis, psoriatic nail disease, and axial disease. However, not every patient will have involvement of all domains and the domains affected can change over time. Complicating the diagnosis is the condition's similarity with other arthritic diseases and potential heterogeneity. In this article, we provide practical guidance for dermatologists for detecting PsA in patients with psoriasis. We also review the available treatment options by each clinical domain of PsA and give advice on how to interpret the results of PsA clinical trials. Through early recognition of PsA in patients with psoriasis and initiation of proper treatment, dermatologists can help to prevent PsA disease progression, irreversible joint damage, and resultant permanent disability, and improve quality of life.