Anorectal Manometry as a Tool to Determine the Necessity of Rectal Biopsy in Children with Severe Chronic Constipation

Constipation is one of the most common disorders of gastrointestinal tract in children. Anorectal manometry (AM) is a non-invasive procedure to determine its etiology. The aim of this study was to present the findings of this diagnostic procedure and relationship between clinical manifestations and determining the necessity of rectal biopsy. This cross-sectional study was performed on 192 children with chronic constipation aged between 6 months to 12 years during 2008-2010 at Amirkola children’s hospital. For unresponsive cases to treatment, AM was performed. The association of fecal incontinency (FI) and withholding status, with recto anal inhibitory reflex (RAIR), internal anal sphincter tonicity (IAT) and necessity of rectal biopsy was analyzed. The mean age of patients was 48.1±27.5 months. RAIR was present in 177 cases (92.2%) and absent in 15 cases (7.8%). The mean IAT was 34.1±19.9 cmH2O. All of the cases with history of FI were RAIR positive (p=0.04) and cases with history of withholding were RAIR positive too (p=0.607). Out of the 6 cases with rectal biopsy, in 4 patients Hirschsprung’s Disease (HD) was proved (2.08% of cases) that in these 4 cases, RAIR was not completely present. This study shows that although RAIR is present in the majority of severe chronic constipated patients, but HD is not ruled out specially in patients without FI and withholding and AM is beneficial in this specific group, for choosing them for probable rectal biopsy.