P295 Correlation between sonographic measurements in inflammatory bowel diseases and biological markers of disease activity

Abstract

Background

Bowel ultrasound is becoming an useful tool in managing inflammatory bowel diseases (IBD). Sonographic measurements correlate well with endoscopic findings and other imagistic methods (MRI, CT) . Several studies attempted to demonstrate a link between bowel wall thickness(BWT) and bowel echo pattern and disease severity expressed by clinical disease indexes and biological markers ( C-reactive protein (CRP), erythrocyte sedimentation rate (ESR). Data from those studies failed to demonstrate a strong correlation but suggested a significant one, especially in ulcerative colitis. Recently, the TRUST study proved that the drop of the measured bowel wall thickness correlated with reduced levels of C-reactive protein after 3 months of treatment in Crohn disease patients, observation that emphasises the role of follow-up bowel ultrasonography.

Methods

42 IBD patients were included in the study (4 diagnosed with ulcerative colitis, 38 with Crohn’s disease). Diagnosis was established endoscopically and histologically and both patients with active and inactive disease were included. Patients with other causes of inflammatory syndrome were excluded (Clostridium Difficile and rotavirus infections, upper tract respiratory infections). Patients were prospectively evaluated sonographically using a 4–8 MHz micro-convex transducer. The examiner was blinded to biological data. Patient were examined in supine position with no special preparation before. For each subject 3 sonographic measurements of bowel wall thickness were noted and bowel echo pattern was evaluated. The sonographic measurements were noted in the corresponding regions according to endoscopic observations. Mean value of BWT was calculated. Biological markers of inflammation were obtained: CRP and ESR.

Results

A good correlation was detected for 2 of the measurements regarding the BWT ( Spearman’s equation, r = 0.529 and r = 0.586, p < 0.001) and CRP but not with the third one (r = 0.464, not statistically significant), this measurement being the closest value to normal. A mean calculated value of the 3 measurements of BWT was correlated with CRP, observing a good correlation too (r = 0.567, p < 0.001). Same statistics were applied to ESR and stronger correlations were obtained (r = 0.618, r = 0.718, r = 737, p < 0.0001. Mean value was strongly correlated as well (r = 0.740, p < 0.0001). Bowel echo pattern ( bowel stratification) correlated well with CRP( r = −0.585, p < 0.0001) and ESR (r = −0.669, p < 0.001).

Conclusions

Sonographic findings (BWT and bowel stratification) seem to correlate well with biochemical markers of inflammation (CRP and ESR), making this technique a good option in managing IBD patients.