P159 Transabdominal ultrasound has high negative predictive value for short-term complications of Inflammatory Bowel Disease
Z. Zelinkova*, B. Kadleckova, B. Repakova
IBD Center, Thalion, Bratislava, Slovakia
Transabdominal ultrasound (US) is a non-invasive, easily accessible cross-sectional imaging technique for bowel examination. It has been shown to have high specificity but traditionally lower sensitivity compared with other cross-sectional techniques and/or endoscopy in depiction of inflammatory bowel disease (IBD) activity. The data available provide comparison of transabdominal US with endoscopy and other cross-sectional imaging but the predictive value of IBD complications is unknown for US. Therefore, the aim of this study was first, to determine the negative predictive value of US in a setting of IBD patients with clinical suspicion of flare and second, to establish the rate of agreement between US and endoscopic and magnetic resonance enterography (MRE) findings.
Between July and October 2014, all consecutive IBD patients with clinical suspicion of IBD flare were referred for transabdominal US at one referral IBD centre. The activity of IBD on US was determined according to standard criteria for each small and large bowel segment. Negative predictive value for short-term complications of IBD, i.e. flare or surgery occurring within 1 to 4 months of US, was calculated. Endoscopic and MRE findings were categorized for each bowel segment and the agreement between US and other techniques was considered only if the agreement on presence of disease activity was achieved for all segments.
In total, 80 US were performed in 79 patients; 62 (78%) with Crohn`s disease, 16 (20%) with ulcerative colitis, 1 pts with IBD unclassified; 52 (65%) women; mean age 35 years, range 19-79. Overall, there were 44 (55%) cases of US findings of active disease, in 6 patients fistula or abscess were found on US. From 36 cases with negative US findings, 35 were in remission without any changes in therapy at the median follow-up of 3 months (range 1 to 5 month); resulting in negative predictive value of 97% (95%CI 85.42 % to 99.54 %).
During the follow-up period, 32 (40%) patients underwent MRE and 21 (26%) ileocolonoscopy, with agreement of US findings in 84% and 73% of cases for MRE and ileocolonoscopy, respectively.
Transabdominal ultrasound has high negative predictive value for short-term complications of inflammatory bowel disease and seems to be a promising tool for rapid and non-invasive triage of IBD patients who do not necessitate further diagnostic work-up.