P117 point-of-care intestinal ultrasound for the detection of postoperative Crohn's disease endoscopic recurrence

Dolinger, M.(1);Stauber, Z.(2);Spencer, E.(1);Kayal, M.(3);Pittman, N.(1);Colombel, J.F.(3);Dubinsky, M.(1);

(1)Icahn School of Medicine at Mount Sinai, Pediatric Gastroenterology, New York, United States;(2)Icahn School of Medicine at Mount Sinai, Internal Medicine, New York, United States;(3)Icahn School of Medicine at Mount Sinai, Gastroenterology, New York, United States;

Background

In patients with Crohn’s disease (CD), following an ileocolic resection (ICR), colonoscopy is the gold standard for the detection of endoscopic recurrence (ER). Colonoscopy, however, is invasive and not easily accepted by patients, particularly for repeated monitoring. In contrast, intestinal ultrasound (IUS) has the advantage of being non-irradiating, non-invasive, well-tolerated, and easy to repeat. The goal of this study was to assess the accuracy of IUS for ER in CD.   

Methods

This was a cross-sectional study of CD patients who underwent IUS during a postoperative clinic visit within 30 days of a planned colonoscopy. Parameters on IUS included bowel wall thickness (BWT), bowel wall hyperemia (BWH; modified Limberg score 0-III), layer stratification, inflammatory fat, and complications. C-reactive protein (CRP), fecal calprotectin (FC), endoscopic healing index (EHI; Prometheus Labs, CA) and Harvey Bradshaw Index (HBI) were also measured. ER was defined as a Rutgeerts Score (RS) > i2. Primary outcome was the association between IUS parameters and ER. Secondary outcomes were the association of IUS parameters with other markers of disease activity. 

Results

Eighteen CD patients (9 female; 29 [19-40] years old), underwent IUS examination 45 [29-99] months post-ICR during a routine clinic visit. Seven (39%) patients were on ustekinumab, four (22%) on adalimumab, two (11%) on infliximab, one (6%) on vedolizumab, and four (22%) on no therapy. ER was found in eight (44%) patients. BWT and BWH in the neo-terminal ileum and BWH at the ileocolic anastomosis were the only IUS parameters associated with ER (Table 1). Neo-terminal ileum BWT was 4.0 [3.2-4.8] mm in patients with ER compared to 2.0 [1.5-2.6] mm without (p=0.04). Neo-terminal ileum BWH was abnormal in six (75%) patients with ER compared to 0% without (p=0.007). BWT of 3.2 mm was the optimal cut point for predicting ER with an: AUROC of 0.82, positive predictive value of 100%, negative predictive value of 97.3%, sensitivity of 75%, and specificity of 100% (Figure 1) vs. a CRP of 10.4 mg/L (AUROC = 0.54) or FC of 1146 µg/g (AUROC = 0.56). Significant correlations were observed between neo-terminal ileum BWT and RS (ρ=0.51, p=0.04) and between BWT and CRP (ρ=-0.56, p=0.023). No correlation was observed between BWT and FC (ρ=-0.04, p=0.91), BWT and EHI (ρ=-0.04, p=0.91), or BWT and HBI (ρ=0.09, p=0.75).



Conclusion

IUS is a feasible, accurate, non-invasive monitoring tool for detection of postoperative CD recurrence. Larger prospective studies are needed to determine how IUS can be integrated in the monitoring of CD patients after surgery.