Einar Ólafur Arnbjornsson, Christina Granéli, Pernilla Stenström, Anna Börjesson
The diagnostic method for Hirschsprung’s disease (HD) involves rectal biopsy to determine the presence of histopathological findings for aganglionosis. Contrast enema (CE) and anorectal manometry help to support the indication for biopsies. Patients with HD lack a rectoanal inhibitory reflex (RAIR) that can be studied using manometry, ultrasound, or a modified contrast enema (CE), which provokes the RAIR with an injection of cold fluid. A question that arises is whether the RAIR also could be visualized with only a specific clinical examination.
Objective: The purpose of the study was to test the hypothesis that the RAIR could be seen with a cold fluid injection into the rectum to identify children without HD and thus to avoid additional investigations involving a CE or rectal biopsy.
Materials and method: In a prospective study all children who were suspected to have HD and who had clinical symptoms were examined using modified CEs. In children in whom the RAIR was found with a modified CE but who still had constipation, further examinations including biopsy were necessary. These children were examined under general anesthesia. Cold water was injected in the rectum to induce and register the RAIR, and a rectal biopsy was conducted. The results were correlated with the modified CE results, histopathological findings from the rectal biopsy, and clinical follow-up outcomes.
Results: The clinical cold fluid examination was not comparable with the modified CE for demonstrating a RAIR in children without HD (p < 0.001) and did not correlate with the rectal biopsy (p < 0.001). Thus, the proportion of unnecessary x-ray examinations, as well as the number of rectal biopsies, could not be reduced with a clinical examination using cold water only
Conclusion: The findings demonstrated that an examination using cold water was not a reliable method for evoking the RAIR..