P0839 Monitoring disease activity using intestinal ultrasonography in patients with Crohn’s disease treated with risankizumab
Authors: Miyakawa M , Shimoyama K , Hamada T , Shimazaki H , Sugiyama K , Nasuno M , Tanaka H 
Published: January 2025

Abstract

Background
Few studies have used intestinal ultrasonography (IUS) to monitor disease activity in patients with Crohn’s disease (CD) treated with risankizumab (RZB). In this study, we investigated the temporal changes in IUS findings among patients with CD who had received RZB.

Methods
We retrospectively collected data from patients with CD who received their first dose of RZB between January 2023 and February 2024, with baseline and subsequent IUS evaluations at our clinic. Patients with a colostomy were excluded from the study. IUS was performed using the Aplio a550 at baseline and at 4, 8, 12, 20, and 28 weeks for each intestinal segment (small bowel, ascending, transverse, descending, and sigmoid colons). Findings for each segment were analyzed using IUS indicators, including bowel wall thickness (BWT) and bowel wall stratification (BWS), while blood flow signals in the intestinal wall were assessed using superb microvascular imaging (SMI). Active BWT was defined by a value of ≥3 mm for the small bowel or ≥4 mm for the colon. The segment with the thickest BWT was considered the representative finding for each patient. BWS were categorized into preserved or loss of BWS. SMI signals were evaluated using our own simplified grading system based on the Limberg score: grade 0, no vascularization; grade 1, short stretches of vascularity as spots; grade 2, longer stretches of vascularity; or grade 3, longer stretches of vascularity reaching the mesentery 1). Changes in BWT, BWT reduction rates, loss of BWS, and SMI grade from weeks 0 to 28 were evaluated.

Results
This study included 28 patients (median age, 31.0 years; median disease duration, 6.0 years), 8 of whom were female. The median BWT at baseline was 5.3 mm. Preservation and loss of BWS were observed in 7 and 21 patients, respectively, and SMI grades of 0, 1, 2, and 3 were observed in 1, 11, 11, and 5 patients, respectively. The BWT and BWT reduction rates at 4, 8, 12, 20, and 28 weeks were 5.2 mm, 5.2 mm, 4.8 mm, 4.6 mm, and 4.5 mm and −1.9%, −2.8%, −10.1%, −12.2%, and −17.4%, respectively. Both values decreased significantly after 8 weeks. Loss of BWS was observed in 78.6%, 75.0%, 71.4%, 60.7%, and 60.7% of patients at 4, 8, 12, 20, and 28 weeks, respectively, and SMI grade 0 was observed in 17.9%, 17.9%, 25.0%, 39.3%, and 50.0% of patients at 4, 8, 12, 20, and 28 weeks, respectively, with a significant increase after 12 weeks.

Conclusion
IUS revealed that BWT changed significantly in patients with CD 8 weeks after treatment with RZB, while blood flow changed significantly 12 weeks post-treatment. Loss of BWS responded poorly even after 28 weeks of treatment. Time-dependent changes should be considered when monitoring disease activity in CD treated with RZB using IUS.

References
1)Nasuno M, Shimazaki H, Nojima M, Hamada T, Sugiyama K, Miyakawa M, Tanaka H. Serum leucine-rich alpha-2 glycoprotein levels for predicting active ultrasonographic findings in intestinal lesions of patients with Crohn’s disease in clinical remission. Medicine (Baltimore). 2023;102(32):e34628. doi: 10.1097/MD.0000000000034628.