SPECIFIC FEATURES OF AXIAL SKELETON INVOLVEMENT IN EARLY PSORIATIC ARTHRITIS (The REMARCA TRIAL)

Abstract

Objective: to optimize the diagnosis of spinal column involvement in early psoriatic arthritis (ePsA).Subjects and methods. 40 ePsA patients (17 men and 23 women) fulfilling the respective CASPAR criteria were examined. Their median age was 36.5 [28.5; 49.5] years; median PsA duration – 13.5 [5; 24] months. The activity of ePsA was assessed using DAS and DAS28. Presence of inflammatory back pain (IBP) according to ASAS criteria and HLA-B27 was evaluated in all the patients; 38 of them underwent pelvic X-ray to reveal significant sacroiliitis (SSI) (Stage II bilateral or Stage III–IV unilateral SSI) and 37 had magnetic resonance imaging (MRI) of sacroiliac joints. A radiologist determined blindly the presence of active sacroiliits (ASI) as bone marrow edema/osteitis.Results and discussion. In ePsA, median DAS and DAS28 were 3.99 [2.99; 4.92] and 4.22 [3.37; 4.8], respectively. IBP was detected in 22 (55%) patients; it was prolonged in 12 (54.5%); IBP episodes were noted in 10 (45.5%). MRI revealed ASI n 15 (40.5%) of the 37 patients; SSI in 11 (28.9%); 17 (42.5%) patients were HLA-B27 positive. In ePsA, there was a very high association of ASI and SSI with IBP (Q = 0.91, р<0.002 and Q=0.83, р<0.002). No significant relationship was found between ASI and HLA-B27. There was no correlation between ASI and DAS (Q=0.06, р>0.9) and SSI and DAS (Q=0.42, р>0.3). A significant association was revealed between ASI and SSI (Q=0.67, р<0.002). Conclusion. In ePsA, ASI and SSI are identified in 40.5 and 28.9% of cases, respectively. ASI and SSI are closely related to IBP rather than to HLA-B27. The activity of peripheral arthritis does not affect the rate of ASI detected on MRI and SSI in patients with ePsA.

Keywords

• psoriatic arthritis
• spinal column involvement
• x-ray study
• magnetic resonance imaging
• sacroiliitis