The skin disease psoriasis can be associated with SpA. Psoriatic arthritis has various presentations, including oligoarthritis (up to 4 joints), distal polyarthritis (more than 4 joints), and a more destructive type of arthritis known as arthritis mutilans. The prevalence of HLA-B27 is higher in these patients than in the general population (30% versus 6%), although not as high as in AS (90%). The course of the disease varies, but it is often similar to the progression seen with RA. Over half of individuals who have the disease for more than 10 years develop deforming arthritis in 5 or more joints. Although methotrexate is sometimes initially used for treatment, biologics and JAK inhibitors appear to be more effective in controlling disease progression.
Parma A, Cometi L, Leone MC, Lepri G, Talarico R, Guiducci S. One year in review 2016: spondyloarthritis. Clin Exp Rheumatol. 2017;35(1):3–17.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.