SAT0388 CHROMOENDOSCOPY AND MAGNIFICATION COLONOSCOPY: ANALYSIS OF THE MUCOSA OF THE COLON AND ILEUM IN PATIENTS WITH SPONDYLOARTRHITIS AND GASTROINTESTINAL SYMPTOMS WITHOUT INFLAMMATORY BOWEL DISEASE
Authors: C. Florez, V. Parra-Izquierdo, W. Bautista-Molano, Y. M. Chamorro-Melo, A. Beltrán-Ostos, D. Jaimes, J. De Avila, A. Ramos-Casallas, D. Acero-M, J. M. Bello-Gualtero, J. Gutiérrez-Sánchez, C. F. Pacheco Tena, L. Chila, P. Chalem, C. Romero-Sánchez
Journal: Annals of the Rheumatic Diseases (2020)

Background: Digital chromoendoscopy with magnification is a technique that identify microscopic inflammation, with a better characterize, highlighting specific gastrointestinal findings showing a good correlation with histopathological features. Spondyloarthritis (SpA) patients with the presence of non-specific gastrointestinal symptoms, subclinical intestinal inflammation is defined by endoscopic and histological techniques Objectives: To detect early structural inflammatory changes by chromoendoscopy and magnification colonoscopy in colonic/ileum digestive mucosa and establish its association with clinical variables in patients with SpA and gastrointestinal symptoms Methods: In total, 180 patients with SpA (ASAS/criteria) were assessed by rheumatologists, of which (n=35) (19.4%) had an indication by a gastroenterologist to perform the chromoendoscopy, magnification colonoscopy and histological analysis. The association between clinical and colonoscopy variables were evaluated using the Chi square or Fisher’s exact test. (Ethical/Code. 2017-023) Results: The average age of the patients included for colonoscopy was 45.4±10.3 years, 57.1% were men and 42.9% presented the HLA-B*27 allele. Axial involvement (91.4%), inflammatory back pain (68.6%) and use of biological therapy (71.4%). High levels of calprotectin (25.7%), CRP&gt;3 (14.3%), positive ESR (22.9%) and positive ANCA (8.6%) was observed. Regarding outcome measures of function and activity, BASDAI &gt;4 (60%) and ASDAS-PCR &gt;2.1 (80.0%) was observed The loss of vascular pattern in the ileum was associated with high levels of calprotectin levels (p=0.002). At microscopic level, 80% of the patients who presented acute inflammation in the ileum had elevated calprotectin (p=0.013). Cryptitis (77.8%) in the ileum was associated with axial involvement (p=0.017). Ulcers and erosion in the ileum were associated with positive ESR (p=0.003). All patients who presented ulcerations and inflammation (64.3%) in ileum were HLA-B27 positive (p=0.029) and (p=0.052) respectively. The 50% of patients with atrophy of villi in ileum were receiving biological treatment (p=0.035) Conclusion: Digital chromoendoscopy and augmentation colonoscopy provided an improved and detailed contrast of the surface of the gastrointestinal mucosa. The tissue sampling showed the loss of vascular pattern as main finding in ileum with interesting associations with fecal calprotectin levels in patients with SpA. The interest of proposing the active search for symptoms, signs and biomarkers of gastrointestinal involvement in patients with SpA without IBD is to define subclinical gastrointestinal involvement and early remission through an endoscopic evaluation and objective histological and propose a specific clinical and therapeutic treatment. Acknowledgments: The Government Institute of Science, Technology, and Innovation, Francisco Jose de Caldas—COLCIENCIAS(Grant No. 130877757442). Universidad El Bosque (PCI-2018-10091), Hospital Militar Central (Grant 2017-023), Clínicos IPS, Gastroadvanced, Fundación Instituto de Reumatología Fernando Chalem-Bogota, Colombia and Biomedicina de Chihuahua, México Disclosure of Interests: None declared