FRI0248 ANTI-CYCLIC CITRULLINATED PEPTIDE ANTIBODY IN PRIMARY SJÖGREN SYNDROME: A MARKER OF EROSIONS ON HIGH RESOLUTION ULTRASOUND OF HANDS AND WRISTS
Authors: Lissiane Guedes, Elaine Leon, Margarete Vendramini, Tamyris Bocate, Karina Bonfiglioli, Eloisa Bonfa, Sandra Pasoto
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Cyclic citrullinated peptides antibodies (anti-CCP) were described in primary Sjögren's syndrome (pSS). However, its possible associations with joint erosions, synovitis and tenosynovitis on high resolution ultrasonography of hands and wrists (US) in pSS are uncertain. <h3>Objectives:</h3> To assess in pSS the US findings, and their possible associations with anti-CCP. <h3>Methods:</h3> We have evaluated 97 consecutive pSS patients (2016 ACR/EULAR Classification Criteria), of both sexes, aged 18-76 years, and without meeting the 1987 ACR classification criteria for rheumatoid arthritis (RA). Twenty RA patients (disease duration &lt;5 years, and without joint deformities), and 80 healthy controls with comparable mean age, gender and ethnicity were also included in a case-control study. Clinical evaluation was performed through a standardized protocol with interview and physical examination. Disease activity was measured according to EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI). US was done in 36 joints and 36 tendon areas of wrists and hands, by the same rheumatologist with expertise in ultrasound, and blinded to autoantibody profile. Patients and controls also underwent X-ray of hands and wrists. Anti-CCP was determined by ELISA using a commercially available kit. <h3>Results:</h3> Frequency of tenosynovitis on US was higher in the pSS group than in healthy controls (36.1 vs. 3.8%, p&lt;0.001). Moreover, the number of tenosynovitis was higher in the former group (p&lt;0.001). Importantly, the presence of erosions on US (27.8 vs. 7.5%, p=0.001) and their number (p=0.005) were greater in the pSS group than in healthy controls, with predominance of small erosions (p=0.015). Comparative analysis between RA and pSS groups revealed that the frequency (p&lt;0.001) and number (p&lt;0.001) of synovitis on US were greater in the former group. The number of grade 1 synovitis was comparable between RA and pSS patients (p=0.354). However, the number of grade 2/3 synovitis were higher in RA than in pSS patients (p&lt;0.001/p&lt;0.001, respectively). Similarly, the number of erosions on US was higher in the RA group compared to pSS group (p&lt;0.001), particularly of moderate/large erosions (p&lt;0.001/p&lt;0.001, respectively). ESSDAI had moderate correlation with the number of synovitis (r=0.302, p=0.003) and tenosynovitis (r=0.343, p=0.001) on US. In pSS patients, US detected 225% more erosions than X-ray. Anti-CCP was more frequent in RA patients (85%) than in pSS (16.5%) (p&lt;0.001). Anti-CCP was more frequent in pSS patients (16.5%) than in healthy controls (4.1%) (p=0.010). In addition, this reactivity was associated with higher mean numbers of erosions in wrists (p=0.018) and proximal interphalangeal joints (p=0.001) on US in pSS patients. <h3>Conclusion:</h3> US detected higher frequencies of tenosynovitis and erosions in pSS patients than in healthy controls, and the numbers of synovitis and tenosynovitis correlated with ESSDAI, suggesting that US is an important tool for the evaluation of these patients. Moreover, grade 2/3 synovitis and moderate/large erosions appear to be relevant for the distinction between pSS and RA. The additional observation that erosions are associated with anti-CCP in pSS seems to characterize a subgroup of patients with a severe underlying mechanism of joint damage. Grant from FAPESP: 2015/03756-4. <h3>References:</h3> [1] Riente L, Scirè CA, Delle Sedie A, et al. Ultrasound imaging for the rheumatologist. XXIII. Sonographic evaluation of hand joint involvement in primary Sjögren's syndrome. Clin Exp Rheumatol. 2009;27(5):747-50. <h3>Disclosure of Interests:</h3> Lissiane Guedes: None declared, Elaine Leon: None declared, Margarete Vendramini: None declared, Tamyris Bocate: None declared, Karina Bonfiglioli Speakers bureau: Has received speaking fees from Roche, Pfizer, Bristol-Myers Squibb, Abbvie and Janssen., Eloisa Bonfa: None declared, Sandra Pasoto: None declared