ABSTRACT

Psoriatic arthritis occurs in approximately 20% of psoriasis patients during the lifetime. Knowing which psoriasis patient proceeds to psoriatic arthritis is important for dermatologists to refer patients to rheumatologists. Some clusters of the risk factor may predict this risk. High PASI scores, involvement of scalp, intergluteal/perianal region and nail are the most important risk factors. Besides, early onset psoriasis and involvement of over 3 regions are other less strong predictors. Marked personal risk factors are uveitis, high body mass index (BMI) (higher the BMI, higher the risk), heavy-lifting works, history of bone and joint trauma, infections requiring antibiotics, periodontitis, female gender, high serum uric acid and presence of Koebner phenomenon. Data regarding smoking are controversial, but smoking seems a protective factor for psoriasis patients with HLA C*06 gene. About 30% of psoriasis patients have non-specific musculoskeletal complaints and these patients are under a higher risk of psoriatic arthritis and should be followed closely. Psoriasis patients with arthralgia in at least one joint and with synovitis/osteitis in magnetic resonance imaging (MRI) were found more likely to develop psoriatic arthritis (PsA). Ultrasonography and MRI seem beneficial to catch PsA patients earlier, but more data are needed to validate these modalities. There are studies on biomarkers, which can enable us to know which psoriasis patient will proceed to PsA, CXCL-20 is the most studied molecule. Lastly, there is an ongoing randomized controlled trial about restrainability of transition from psoriasis to psoriatic arthritis (PAMPA study). This study will provide important information about this issue.