Anal canal and sphincter function in children with Hirschsprung disease after definitive surgery

Abstract

IntroductionAnorectal manometry may be useful to objectively evaluate anorectal function following definitive pullthrough for Hirschsprung Disease (HD) but there is little published data. Our study aims to investigate anorectal manometry findings and their association with bowel function. MethodologyThis was a prospective observational study. Convenience sampling method was used to recruit all HD patients who had definitive pullthrough from January 2019 to December2020 in our institution. High-resolution anorectal manometry (HRAM) was used to record anal resting pressure (ARP), length of high-pressure zone (HPZ), and presence/absence of recto-anal inhibitory reflex (RAIR). The Paediatric Incontinence/Constipation Scoring System (PICSS) was scored for all participants. PICSS is a validated questionnaire with scores mapped to an age-specific normogram to denote constipation, incontinence, and their combinations. Non-parametric and chi-square tests at significance p<0.05 were conducted to examine the relationship between PICSS categories and manometry findings. Ethical approval was obtained. ResultsThere were 32 participants (30 boys). Median age at participation was 26.5 months (range: 13.8–156). Twenty-four (75%) had transanal pullthrough, 8(25%) underwent Duhamel procedure. PICSS scored 10(31.3%) as normal, 8(25%) as constipation, 10(31.3%) as incontinent, and 4(12.5%) as mixed. RAIR was present in 12 patients (37.5%). HPZ, maximum ARP, mean ARP were comparable across all PICSS groups without statistically significant differences. Presence of RAIR was not significantly associated with any PICSS groups (p = 0.13). ConclusionBowel function does not appear to be significantly associated with HRAM findings after definitive pullthrough for HD, but our study is limited by small sample size. RAIR was present in 37.5% patients after pullthrough. Level of EvidenceLevel II