Symptoms dermatologists should look for in daily practice to improve detection of psoriatic arthritis in psoriasis patients: an expert group consensus

Background Up to 29% of patients with psoriasis seen by dermatologists have undiagnosed psoriatic arthritis (PsA). As early detection of PsA may be associated with improved joint and skin outcomes, it is essential for dermatologists to improve their ability to diagnose PsA. Skin and nail features of psoriasis associated with PsA are well known to dermatologists but they may feel less confortable assessing other symptoms and they rarely use PsA screening questionnaires. Objective To develop a limited list of clinical signs and symptoms that a dermatologist should be looking for in a psoriasis patient in addition to specific skin features and nail involvement, to improve PsA detection. Methods A systematic search was performed in Pubmed, Cochrane and Embase databases to identify clinical key symptoms associated with PsA. It yielded 27 studies in which we extracted a list of clinical signs and symptoms observed in PsA and submitted it to a panel of dermatology experts through a DELPHI selection process. The experts had to determine which minimal set of signs and symptoms dermatologists should look for in daily practice to improve detection of PsA in patients with psoriasis. Results The four items that received a score higher than 90% in the DELPHI process were finally selected. Those items were as follows: peripheral inflammatory pain (100%), axial inflammatory pain (95.3%), dactylitis (93%), buttock and sciatic pain (90.7%). The remaining items: distal interphalangeal joints (DIPs) involvement (83.7%), Talalgia (79.1%), swollen Achille's tendon (41.9%), costo-chondral involvement (32.6%), uveitis (7%), mouth ulcerations (2.3%), were not retained. Conclusion We propose a set of four items to screen psoriasis patients for psoriatic arthritis for routine clinical use by dermatologists.