Rectal diameter measured by transabdominal ultrasonography for monitoring treatment response in children with functional constipation
Year: 2026
Type: article
Abstract: BACKGROUND Transabdominal ultrasonography (USG) is a noninvasive tool for detecting fecal impaction in children with functional constipation (FC) and may predict treatment response. However, supporting evidence remains limited and controversial. AIM To evaluate changes in rectal diameter (RD) and anterior rectal wall thickness (AWT) measured by USG in children with FC after treatment with polyethylene glycol (PEG) for 8 weeks. METHODS This substudy of a randomized controlled trial included children aged 6 months to 18 years diagnosed with FC according to the Rome IV criteria at King Chulalongkorn Memorial Hospital (May 2024-February 2025). Participants received either commercial PEG or PEG-Chula as laxatives for FC. USG was performed at baseline and at 1, 4, and 8 weeks by the primary investigator. RD and AWT were measured following Klijn’s technique. RESULTS Of the 52 enrolled children, 44 completed all four visits. The median age was 50.5 [interquartile range (IQR): 28-92.5] months, and 65.9% were female. The median FC duration was 19.5 (IQR: 12-36) months. Stool frequency and consistency improved significantly over 8 weeks, with no difference between the commercial PEG and PEG-Chula groups. The mean RD decreased significantly from 2.70 cm (95%CI: 2.51-2.88) at baseline to 2.46 cm (95%CI: 2.30-2.62) at week 1, 2.45 cm (95%CI: 2.30–2.60) at week 4, and 2.33 cm (95%CI: 2.18-2.48) at week 8. AWT remained 0.29 cm (95%CI: 0.27–0.32) at baseline and 0.29 cm (95%CI: 0.26–0.30) at week 8 (P = 0.997). The time since the last defecation to USG significantly influenced RD (P = 0.030) but not AWT (P = 0.382). CONCLUSION USG-measured RD decreases significantly with effective PEG treatment and may serve as a useful noninvasive marker for monitoring treatment response in children with FC.
DOI: 10.5409/wjcp.119251
Language: English
Subfield: Gastroenterology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7163181630