Early Intestinal Ultrasound Predicts Intravenous Corticosteroid Response in Hospitalised Patients With Severe Ulcerative Colitis

Background and aims: Our aim was to determine if transabdominal intestinal ultrasound changes after 48 ± 24 h of intravenous corticosteroids can predict treatment outcomes in hospitalised patients with severe ulcerative colitis.

Methods: We performed a blinded observational multicentre study. Ultrasound parameters were assessed before treatment initiation, after 48 ± 24 h, and 6 ± 1 days. Treatment response was determined within 7 days by two outcome measures: 1] partial Mayo score reduction; 2] no administration of rescue therapy.

Results: Out of 69 recruited patients, 56 were included in the final analysis, with 37 responders. The colon segment with the highest baseline bowel wall thickness was analysed, being the sigmoid in all patients. There was no difference in baseline bowel wall thickness between responders and non-responders in the partial Mayo score outcome. At 48 ± 24 h, a significant difference between responders and non-responders was identified in both absolute bowel wall thickness [median 3.1 mm vs 4.9 mm; p <0.0001], absolute reduction [-1.9 mm vs -0.2 mm; p <0.001], and relative reduction [-35.9% vs -4.1%; p <0.0001]. A ≤20% reduction had a sensitivity of 84.2% (95% confidence interval [CI] 60.4, 96.6%) and a specificity of 78.4% [61.8, 90.2%] for determining non-response [area under the curve 0.85]. In the multivariable analysis, a >20% reduction had the highest odds ratio (22.6 [4.2, 201.2]; p = 0.001) for determining response. Similar results were seen for the rescue therapy outcome.

Conclusions: Changes in bowel wall thickness, after 48 ± 24 h following intravenous corticosteroid treatment in hospitalised patients with severe ulcerative colitis, identify responders with high accuracy and might be used as an early marker to guide accelerated rescue therapy.