SAT0386 USEFULNESS OF THE FECAL CALPROTECTIN AS SCREENING TOOL FOR INFLAMMATORY BOWEL DISEASE IN PATIENTS WITH SPONDYLOARTHRITIS AND NO DIGESTIVE SYMPTOMS
Authors: C. Merino Argumánez, M. Espinosa, C. Ramos Giráldez, O. Rusinovich, N. De la Torre, J. Campos Esteban, Y. Gonzalez Lama, V. Matallana, M. Calvo Moya, B. Ruiz Antorán, I. Vera, G. Vázquez, J. L. Andréu Sánchez, J. Sanz
Journal: Annals of the Rheumatic Diseases (2020)

Background: Fecal calprotectin (FC) is a biomarker of bowel inflammation widely spread in diagnosis and follow-up of inflammatory bowel disease (IBD). It is classically estimated that 5% of patients with axial spondyloarthritis (SpA) also have IBD; coexistence of both conditions has definite impact in clinical decisions. Proactive detection of both diseases should be advisable, though appropriate screening tools are still lacking. Objectives: To evaluate the usefulness of FC for the diagnosis of IBD in patients diagnosed with SpA with no clinical suggestive manifestations or previous diagnosis of IBD. Methods: Patients from a Rheumatology clinic diagnosed with SpA who met ASAS criteria and did not present digestive symptoms suggestive of IBD were consecutively included. Demographics, clinical and analytical data of SpA (uveitis, HLA B27, acute phase reactants) at the time of inclusion, and treatment history were collected. Patients with a positive FC (&gt; 50 mg/Kg) underwent ileocolonoscopy with biopsies of colon and terminal ileum. Patients who were recommended to avoid NSAIDs 2-4 weeks before stool collection and endoscopy. Patients with no endoscopic findings underwent a second determination of fecal calprotectine. If persisted positive, capsule endoscopy was performed to evaluate small intestine. Results: 98 patients included; 47% male, mean age 46.1 (20-74) years. BASDAI 3.6 ± 2.5. HLA B27 positive in 78% of patients, high ESR in 31.6%, high CRP in 9.2%. FC positive in 49 patients (50%): mean 147 mg/kg (range 0-3038). 47 underwent ileocolonoscopy: In 13 cases (26.5%), endoscopic findings were suggestive of IBD (7 Crohn’s disease and 1 ulcerative colitis). Microscopic inflammation was found in 2 additional cases. Among those 34 patients with normal ileocolonoscopy, 16 patients refused further investigations; among the remining 18 patients, a second FC was positive in 16. Capsule endoscopy showed findings suggestive of small intestine IBD in 6 additional patients. In patients with high FC levels, those with high CRP and ESR were more likely to have IBD (29% v 16% and 29% v 12% respectively). Patients with a history of uveitis (18% vs 12%) or psoriasis (33% v 16%) also had a higher prevalence of IBD, although none of those differences reached statistical significance. FC was higher in smokers (72%v 44%; p=0.03). There were no significant differences regarding HLA B27. No statistically significant differences were found in FC between patients with high FC who were diagnosed with IBD and those who were not. Conclusion: In our study, patients with SpA and no clinical feature suggestive of IBD who showed FC&gt; 50 mg/kg had high prevalence of IBD, which could indicate the usefulness of FC as screening tool for IBD in patients with SpA. Patients with SpA and other immune-mediated condition or elevated CRP, seem to be more likely to have subclinical IBD. Disclosure of Interests: None declared