Rectal biopsy in the investigation of constipation

Aims-To develop criteria to prevent unnecessary rectal biopsies in constipated children. Methods-A retrospective review of 186 rectal biopsies from 141 children, comparing the age at onset of symptoms with the diagnosis of Hirschsprung's disease. Results-All of the 17 children with Hirschsprung's disease had the onset of symptoms before the age of 4 weeks. Twenty seven children had delayed passage of meconium (more than 48 hours) of whom 10 had Hirschsprung's disease. Three children with Hirschsprung's disease were referred after the neonatal period (2 months, 11 months, and 3 years) but all had the onset of symptoms before 4 weeks of age. Conclusion-If the age at onset of constipation is after the neonatal period, a rectal biopsy is unnecessary.