P332 External validation of intestinal ultrasound scores to detect endoscopic activity in children and adults with Crohn's disease: A prospective cohort study

Aronskyy, I.(1);Spencer, E.(1);Kellar, A.(1);Pittman, N.(1);Dubinsky, M.(1);Dolinger, M.(1)*;

(1)Icahn School of Medicine at Mount Sinai, Pediatric Gastroenterology, New York, United States;

Background

Intestinal ultrasound (IUS) scores were developed for adults and children with Crohn’s disease (CD) but have not been externally validated with endoscopy. This study aimed to externally validate all CD IUS scores with endoscopy.

Methods

Prospective cross-sectional study of children and adults with CD who underwent IUS and colonoscopy within 60 days. The International Bowel Ultrasound Segment Activity Score (IBUS-SAS), Simple Ultrasound Score for Crohn’s disease (SUS-CD), Simple Ultrasound Activity Score for Crohn’s disease (SUAS-CD), and Simple Pediatric Activity Ultrasound Score (SPAUSS) were compared to the Simple Endoscopic Score for Crohn’s disease (SES-CD). Primary outcomes were the area under the receiver operating curve (AUROC) for each IUS score for moderate (SES-CD > 5) and any (SES-CD > 3) CD activity. Secondary outcome was the correlation of IUS scores and SES-CD.

Results

82 CD patients (53 (65%) children, 29 (35%) adults, 41 (50%) female; 50 (61%) ileocolonic disease location) underwent IUS of 150 (74 (49%) terminal ileum) bowel segments with IUS scores and SES-CD. In both children and adults, all scores performed with high accuracy to detect SES-CD > 5 and moderate accuracy to detect SES-CD > 3. To detect SES-CD > 5 in children, a SUAS-CD > 4.5 had the highest AUROC [95% CI] =0.91 [0.85-0.97] (sensitivity=90%, specificity=81%), followed by an IBUS-SAS > 37.8 (AUROC=0.89 [0.83-0.96]), SPAUSS > 4 (AUROC=0.89 [0.81-0.96]), and SUS-CD > 2 (AUROC=0.88 [0.80-0.95]). To detect SES-CD > 5 in adults, an IBUS-SAS > 34.2 had the highest AUROC=0.85 [0.71-98] (sensitivity=70%, specificity=87%) followed by a SAUS-CD > 5.45 (AUROC =0.84 [0.71-0.98]), SUS-CD > 1 (AUROC=0.81 [0.65-0.97]), and SPAUSS > 5 (AUROC=0.78 [0.65-0.97]). To detect SES-CD > 3, SPAUSS > 4 (AUROC=0.78 [0.69-0.87], sensitivity=56%, specificity=92%) and SUS-CD > 3 (AUROC =0.78 [0.68-0.86], sensitivity=56%, specificity=89%) had the highest accuracy in children followed by a SAUS-CD > 4.5 (AUROC=0.74 [0.63-0.86]) and IBUS-SAS > 34 (AUROC=0.73 [0.62-0.84]). In adults, SAUS-CD > 2.68 and IBUS-SAS > 11.2 (AUROC = 0.68 [0.50-0.85], sensitivity=63%, specificity=72%) had the highest accuracy to detect SES-CD > 3 followed by a SUS-CD > 2.5 (AUROC = 0.65 [0.50-0.81]), and SPAUSS > 6 (AUROC = 0.61 [0.45-0.77]). IUS scores moderately correlated with SES-CD in children and adults, of which the IBUS-SAS had the highest (r=0.66 in children vs. r=0.57 in adults).

Conclusion

CD IUS scores are accurate for the detection of endoscopic activity in children and adults. IUS scores may be more accurate in children and correlate better with endoscopy but more studies are needed. This data supports the use of IUS as an accurate monitoring tool, reflective of endoscopic activity.