AB0964 Psoriatic arthritis (PsA) with positive rheumatoid factor (RF) versus psoriatic arthritis with negative RF

Abstract

BackgroundRheumatoid factor (RF) has been detected in several patients with psoriatic arthritis (PS). It is likely that its positivity is linked to a very specific clinical, biological and/or evolutionary profile of PsA.ObjectivesThe objective of our study was to evaluate the frequency of positive rheumatoid factor during PsA, and to define the characteristics and factors related to this positivity.MethodsMonocentric observational cross-sectional study including 84 patients with PsA, fulfilling the CASPAR criteria, and hospitalized in our rheumatology department in University Hospital Hassan II of Fez, on the period lying between January 2012 and October 2021. A threshold greater than 20Ui/ml of defines RF positivity.ResultsOur study included 84 patients, the average age was 57 +/- 13 years. The sex ratio was 0.35 M/F, the average duration of disease progression was 6 years +/- 8 years. 47.6% of patients had a positive RF (40 patients) while 52.4% of patients had a negative RF (44 patients).In bivariate analysis, PsA with positive RF had an earlier age of the disease onset (p=0.017), was more frequent in chronic smokers (p=0.045), and showed more enthesis damage (p=0.046). Also, patients with PsA and a positive RF had a higher biological inflammatory syndrome (p=0.013) in particular CRP (p=0.007), higher Basdai and DAPSA (p=0.021) (p=0.021) respectivelyIn multivariate analysis, enthesis damage involvement was significantly linked to RF positivity (p=0.039, OR=3, IC=1.059-8.495), as was the biological inflammatory syndrome (p=0.010, OR=3.875, IC=1.382 -10.766).ConclusionIn our study, PsA with positive RF is found to be earlier and more severe in comparison with PsA with negative RF, and more frequently adopts the peripheral enthesitic form.