Role of noncontrast enhanced abdominal ultrasound in the diagnostic assessment of pediatric inflammatory bowel disease

Abstract

Objectives: Assessment of small bowel involvement when diagnosing inflammatory bowel disease (IBD) delineates clinical subtype and disease extension. The gold standard for small bowel assessment is magnetic resonance enterography (MRE), but MRE is not always feasible for children. Standard, non-contrast enhanced abdominal ultrasound is an acceptable alternative. The study aimed to evaluate the utility of ultrasound in the diagnostic work-up of pediatric IBD to identify small bowel involvement.

Methods: A retrospective study was conducted among children (< 18 years) who had abdominal ultrasound during assessment for IBD (2019-2023) at Christchurch Hospital, New Zealand. Descriptive analysis compares small bowel ultrasound to MRE, endoscopy and histology.

Results: The cohort comprised 47 children, mean age 9.9 years (± 4.1), 23 (49%) males and 42 (89%) with Crohn's disease. All had endoscopy and histology data available for comparison, and 26 had MRE. Fourteen (30%) had no small bowel disease on ultrasound, MRE, endoscopy, or histology. Ultrasound confirmed small bowel disease diagnosed by other modalities for 12 (26%). Ultrasound identified small bowel disease for 7 (15%) that had not been seen during the diagnostic process by MRE, endoscopy or histology, possibly due to the limitations of endoscopy and time-delays between diagnosis and MRE. Small bowel disease was not picked up on ultrasound for 14 (30%) children, disease locations being duodenum (n = 6), TI (n = 5), proximal ileum (n = 3), and jejunum (n = 2).

Conclusions: Abdominal ultrasound is a valuable resource for assessing disease extent in suspected pediatric IBD. This study highlights the clinical benefit and feasibility of a multi-modal diagnostic approach.

Keywords: Crohn's disease; children; diagnosis; small bowel; ultrasonography.