Do oro-anal transit markers predict which children would benefit from colonic manometry studies?

The aim of the study was to compare oro-anal transit time (OTT) measured by radio-opaque markers with colon motility (CM) findings in children with chronic constipation and to assess clinical outcomes in children with chronic constipation evaluated by OTT and CM studies.

Twenty-four children with chronic constipation (12 girls; median age 12 years [3-18 years]; median symptoms 87 months [6-186 months]) who underwent OTT and CM studies were reviewed. The OTT was determined using commercially available Sitzmarks. Patients were studied for a median of 23 months (4-60 months) and outcomes reviewed.

All 5 children with normal OTT had normal CM; however, only 47% (9/19) of children with slow OTT had an abnormal CM. The abnormal CM findings were total colonic pseudo-obstruction in 3 and left colonic pseudo-obstruction in 6 children. Of the 9 children with abnormal CM, 5 were managed surgically, 1 with medicine escalation, and 3 were lost to follow-up; all 6 children with known follow-up have more bowel movements and less soiling. Of the 15 children with normal CM, 10 were managed with medication escalation, 3 with behavioral intervention, and 2 surgically. Of these 15 children, 8 improved, 1 did not change, 2 worsened, and 4 were lost to follow-up.

OTT studies may be helpful to predict which children should be referred for CM studies. Normal OTT studies may predict normal colon manometry; however, abnormal OTT studies may not predict abnormalities in colonic manometry in children with chronic constipation. Therefore, patients with slow transit marker studies should be assessed by colon manometry to evaluate colon neuromuscular integrity.