Introduction In patients presenting with symptoms suggestive of IBD (abdominal pain and/or diarrhoea) in common with ECCO guidelines colonoscopy is the first line test at our institution. In our practice magnetic resonance enterography (MRE) is then performed in those patients where there is a continuing clinical suspicion of small bowel Crohn’s disease.

However in patients who present to non-IBD physicians Computed tomography of the abdomen and pelvis with contrast (CTAP) is often the first line investigation.

In this situation MRE is commonly performed to exclude small bowel disease following review in the gastroenterology clinic. We are not aware of studies that have evaluated the additional diagnostic yield of MRE in this clinical scenario.

Aim to establish the additional diagnostic yield of MRE in patients previously investigated with CTAP and ileo-colonoscopy.

Methods Our radiology department maintain a prospective electronic database. We searched for all patients who underwent CTAP followed by MRE within the same 12 month period between February 2005 and February 2013. Electronic medical records were then reviewed.

Results 80 patients were identified. The mean age at time of MRE was 49 (range 17–87), 45 (56%) were female. Indication for these investigations were: assessment of known Crohn’s disease; 18 (23%), abdominal pain; 34 (43%). Mean time between CTAP and MRE; 127 days (range 3–352). Final diagnosis was Crohn’s disease; 37 (45%), coeliac disease; 4(5%), irritable bowel syndrome 4(5%). In 11(14%) MRE added further information or changed the management for the patient. Of this group in 3 patients MRE identified terminal ileal (TI) inflammation that was not identified at CTAP. In two of these cases ileal-colonoscopy collaborated TI inflammation and in the third case capsule enteroscopy confirmed TI inflammation. In all three the final diagnosis was Crohn’s disease. Overall MRE identified one (1.25%) patient with possible CD that was missed at CTAP and ileo-colonoscopy.

Conclusion In this study the diagnostic yield of MRE in patients previously investigated with ileo-colonoscopy and CTAP was low. This suggests that MRE has a limited diagnostic role in this specific situation and should be reserved for those patients where clinical suspicion remains high despite negative CTAP and ileo-colonoscopy or to further define complex disease.

Disclosure of Interest None Declared.