P317 Key features of bowel ultrasonography in managing inflammatory bowel disease patients

Abstract

Background: Bowel ultrasonography (BUS) is an accurate imaging method for detecting and monitoring inflammatory bowel disease (IBD) patients [1]. This technique is recommended by current guidelines besides gold standard endoscopic assessment in managing IBD patients [2]. Several BUS characteristics strongly correlate with biological markers of inflammation suggesting that these tests could be used in monitoring IBD patients [3] but is yet unknown how these features predict the patient's evolution. Method(s): Our study included 95 consecutive IBD patients (24 diagnosed with ulcerative colitis, 71 with Crohn's disease) with both active and inactive disease at presentation. IBD diagnosis was established endoscopically and histologically. Patients with superimposed infection (viral or bacterial) and patients that had solely rectal involvement of the disease were excluded. BUS was conducted at baseline by one skilled examiner blinded to biological data. Biological markers were evaluated at baseline and all cases were prospectively followed-up for need of therapy escalation during the next 6 months. The following BUS characteristics were registered in every patient: bowel wall thickness, alteration of wall structure, thickened mucosa or submucosa, presence of hyperechoic spots in the mucosal wall, irregularity of the external wall, Doppler signal, presence of mesenteric hypertrophy, presence of lymph nodes, and an overall assessment of the examination. No special preparation was needed before BUS. Result(s): Of all the monitored sonographic features, the following characteristics correlated with the need of increasing treatment in the following 6 months: bowel wall thickness, altered structure of the wall, hypertrophic mucosa, Doppler signal, and the overall assessment of the examination (p<0.001). The presence of the lymph nodes, hyperechoic spots in the mucosa, thickened submucosa and the irregularity of the external wall were not statistically significant correlated with the need of treatment escalation. The strongest correlation with the need for increasing treatment was documented for a mean bowel wall thickness > 5 mm and for Doppler signal presence in the bowel wall (p<0.00001). In the multivariate analysis Doppler signal presence was the only independent predictor for the need treatment escalation during a 6-month follow-up. Conclusion(s): The most important sonographic features with an impact on therapeutic decision making in IBD patients are: bowel wall thickness, Doppler signal, altered stratification of he wall and mesenteric hypertrophy. In our analysis, Doppler signal was the only independent predictor for the need of step-up therapy.