TOPLINE:

In children hospitalised with acute severe ulcerative colitis on intravenous corticosteroids, intestinal ultrasound (IUS) parameters such as colonic wall thickness (CWT) were associated with non-response to intravenous corticosteroids, as indicated by the need for treatment escalation.

METHODOLOGY:

• Researchers conducted a prospective study across 11 paediatric inflammatory bowel disease centres in Europe to evaluate whether repeated IUS scans could predict short-term treatment outcomes in children with acute severe ulcerative colitis.
• They included 60 consecutive biologic-naive children with acute severe ulcerative colitis (median age at diagnosis, 13.5 years; 61.7% girls), defined by a Pediatric Ulcerative Colitis Activity Index score ≥ 65, who were hospitalised at diagnosis or disease relapse and received intravenous corticosteroids between 2020 and 2024.
• Each child underwent two IUS scans: the first within 48 hours of hospital admission and the second between days 5 and 7 post-admission.
• Researchers assessed various IUS parameters including CWT and colonic wall layer stratification, and Milan ultrasound scores were calculated across four colonic quadrants.
• Response to intravenous corticosteroids was assessed. The need for escalation to second-line therapy within 10 days of hospital admission was referred to as non-response, in which infliximab was initiated as a rescue therapy. Among responders, medical treatment was chosen for maintaining remission.

TAKEAWAY:

• Overall, 65% of children did not respond to intravenous corticosteroids and required escalation to second-line therapy; non-responders had higher CWT than responders in the left lower quadrant (median, 6 vs 4.2 mm; P < .001) and in the left upper quadrant (median, 5 vs 4 mm; P = .003).
• CWT and Milan ultrasound scores in the left lower quadrant were strong predictors of steroid resistance, with areas under the receiver operating characteristic curve (AUCs) of 0.819 and 0.834, respectively (P < .001 for both). The cutoff of 5 mm was identified for CWT and of 7.8 was identified for Milan ultrasound scores, with a sensitivity above 80%.
• Of children who did not respond to steroids, 16.7% required short-term colectomy within 8 weeks due to medical therapy refractoriness. In the second IUS scan, CWT and Milan ultrasound scores in the left lower quadrant and left upper quadrant predicted first-line therapy failure (P < .05 for respective AUCs).
• Among 50 children who responded to the therapy, clinical remission was noted in 64%. Children who achieved steroid-free clinical remission at week 8 vs those who did not had lower Milan ultrasound scores (median, 5.3 vs 8.7; P < .001) and CWT (median, 3.5 vs 5 mm; P = .037) in the left lower quadrant at the second IUS scan.

IN PRACTICE:

"IUS may provide valuable, non-invasive information for early identification of corticosteroid resistance and poor short-term outcomes in pediatric ASUC [acute severe ulcerative colitis]. LLQ [left lower quadrant] and LUQ [left upper quadrant] CWT and MUS [Milan ultrasound scores] are particularly informative, and their incorporation into routine care pathways may optimize risk stratification, guide timely escalation of therapy, and support clinical decision-making in this vulnerable population," the authors of the study wrote.

SOURCE:

This study was led by Luca Scarallo, Gastroenterology and Nutrition Unit, Meyer Children's Hospital IRCCS, Florence, Italy. It was published online on March 16, 2026, in Gastroenterology.

LIMITATIONS:

The study had a relatively small sample size. The absence of a study-specific treatment protocol may have introduced some variability in medical management. Additionally, the quadrant-based scanning approach may have limited anatomical granularity regarding precision in localisation.

DISCLOSURES:

This study did not receive any funding. Some authors reported serving as advisory board members and receiving grants, honoraria, consultation fees, or royalties from various companies.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.