AB0853 Development of inflammatory bowel disease during anti-TNF therapy in patients with spondyloarthritis

Background The spondyloarthritis (SpA) are a group of chronic inflammatory diseases with common clinical, pathogenic, radiologic and genetic characteristics. The anti-TNF drugs have shown be efficacious when treatment with NSAIDs and DMARDs fails. However, the paradoxical onset of these diseases have been reported during anti-TNF therapy, specifically psoriasis, inflammatory bowel disease (IBD) and uveitis, in both patients with history of SpA and patients with not-related diseases as rheumatoid arthritis. We present a series of 4 cases with previous SpA history who developed IBD during anti-TNF therapy. Objectives To describe the clinical and immunological characteristics, and outcome of patients with SpA who developed IBD during anti-TNF therapy. Methods A retrospective, observational and transversal study was carried out. The register of biological therapies of a university hospital was revised and SpA patients who developed IBD during anti-TNF therapy were identified, then obtaining their medical records for data recollection and analysis. Results 82 SpA patients were identified (including ankylosing spondylitis [AS], psoriatic artritis, undifferentiated and juvenile SpA), who received 219 treatment doses. 68 patients received [IFX] (253 patient-years), 88 patients adalimumab [ADA] (225 patient-years) and 63 con [ETN] (181 patient-years). 4 cases of IBD were identified and all of these occurred with ETN, with an accumulated incidence of 2,2 cases by 100 patient-years of exposure. 2 patients were males and 2 females, with a mean age of 44,2 years (23-56). The elapsed time since beggining of anti-TNF therapy until IBD diagnose was 29,5 months (2-59). All the patients were previously diagnosed of SpA, 3 AS and 1 undifferentiated SpA, being all of them HLA-B27 positive. None of them had previous history of digestive complaints, but there was positive family history of IBD in 2 of them. Symptoms that guided to diagnose were persistent diarrhoea in 2 patients, whereas the other 2 presented intestinal obstruction and rectorrhagia. Endoscopic and histophatological findings were compatible with Crohn’s disease (CD) in 2 patients and with ulcerative colitis (UC) in the other 2. ETN was withdrawn in all patients and switched to a monoclonal antibody with control of IBD, but 1 patient presented palmoplantar pustulosis as second paradoxical event during IFX treatment. Conclusions Although SpA patients have a increased background risk of IBD development, the clinical onset of IBD during anti-TNF therapy is a rare event and most of the cases have been reported with ETN. This drug, unlike of monoclonal antibodies, does not control the inflammatory activity in IBD and its use is not recommended in these diseases. Most of cases of IBD during anti-TNF therapy correspond to CD, but UC has been reported too. In this series, we found the same number of both. It’s recommendable to watch the occurrence of suggestive symptoms of IBD in all patients who receive anti-TNF therapy, and perform a more exhaustive study in patients with risk factors as family history of IDB or SpA diagnose. Disclosure of Interest None Declared