Psoriatic arthritis: state of the art review.

Psoriatic arthritis (PsA) accounts for around 20% of referrals to the early arthritis clinic and presents a significant diagnostic and management challenge. Early diagnosis is important to prevent long term functional disability and to ensure optimal management of arthritis and key comorbidities. From the rheumatologist's perspective, the differential diagnosis includes rheumatoid arthritis, gout and other inflammatory arthritides. Once diagnosed, it is essential to assess the disease fully, including arthritis, enthesitis, dactylitis, skin/nail disease and axial involvement. Using this information, appropriate treatment can be planned using therapies that are effective at treating the relevant domains of disease. Despite poor data, traditional disease-modifying anti-rheumatic drugs are commonly used and have been effective in observational studies. Following tumour necrosis factor inhibitors, which have proven excellent efficacy in multiple domains of PsA, new biologics are available or in development and will improve treatment options for people with refractory PsA. © Royal College of Physicians 2017. All rights reserved.