Introduction
Data on using Intestinal Ultrasonography (IUS) for monitoring colonic lesions and treatment response in ulcerative colitis (UC) are still limited and most results are from single-center units usually performed in centers with a special expertise in IUS.
Aims & Methods
Our multicenter study aimed to identify predictive factors and monitor early response after different therapies in UC.
Methods: From July 2022 to Oct. 2023, we conducted a multicenter study at 5 IBD centers. UC pts starting biological therapies or small molecules were included, and underwent colonoscopy (CS), IUS, clinical assessments at baseline and at 12 weeks. All pts received standard of care therapy according to ECCO guidelines. Exclusion criteria were disease limited to the rectum, active infections, and inability or contraindication to perform CS and/or IUS within the time intervals established by the study. Colonic wall thickening (CWT), vascularization (CWF), Milan Ultrasound Criteria (MUC), Mayo endoscopic score (MES), total/partial Mayo score were evaluated.
Results
Eighty-four UC patients were enrolled and eligible for starting biological therapy or small molecules. Forty-nine out of 84 pts (58.4%) were male, 40 pts (47.6%) had extensive colitis and 44 pts (52.4%) had left colitis, with a disease duration of 20 months (1-336); 53 pts (63%) were steroid-dependent/refractory. Forty-one pts (48.9%) started anti-TNFs, 14 pts (16.6%) anti-IL12/23 or anti IL 23, 16 pts (19%) vedolizumab, and 13 pts (15.5%) JAKi. After 12 weeks, 39 out of 84 patients (46.4%) had partial Mayo score<2, 31 patients (36.9%) 2-4, 10 patients (11.9%) 5-7, and 4 patients (4.76%) >7. Forty-three out of 84 patients (51.2%) had MES=0-1, while 41 out of 84 patients (48.8%) had MES=2-3. Fifteen out of 84 patients (17.9%) had ultrasonographic response (defined as CWT<3mm) and 26 out of 84 patients (30.1%) had MUC<6.2 (1). Logistic regression was performed to evaluate the relationship between clinical/endoscopic and ultrasonographic characteristics and early IUS response at 3 months. Univariable analysis showed that active smoking ([RR], 1.9; 95% CI, 1.2–3.1, p<0.005), appendectomy ([RR], 2.5; 95% CI, 1.9–3.2, p<0.0001), partial Mayo score <2 ([RR], 2.18; 95% CI, 1.5–3, p<0.001) were associated with higher risk of response at 3 months. Inversely, severe endoscopic lesions (MES 3) (RR, 0.3; 95% CI, 0.2–0.6; p<0.0001), presence of lymph-nodes, mesenteric hypertrophy and vascularization (p<0.001, RR 0.36, 0.28, 0.45 respectively) were associated with a lower risk of response at 3 months. CWT was associated with a lower risk of response at 3 months (RR 0.66, 95% CI, 0.53-0.81, p<0.0001) and every increased mm was associated with a 34% reduction of IUS response. MUC was associated with a lower risk of response at 3 months (RR 0.78, 95% CI, 0.7-0.87) and every increased of one point was associated with a 22% reduction of IUS response. In the multivariable analysis, CWT and MUC were the only predictive factors associated with IUS response at 3 months (RR 0.70, 0.78 respectively, p<0.04). A CWT<5.5 mm showed a 2.5 risk of treatment response at 3 months.
Conclusion
Our multicenter study demonstrated that IUS allows close monitoring of treatment in UC. MUC, and in particular CWT, are valuable parameters to predict early response in UC.
References
1)Allocca M, et al. Predictive value of Milan ultrasound criteria in ulcerative colitis: a prospective observational cohort study. United European Gastroenterol J. 2022; 10:190-7.
