Children with functional constipation often report that they do not feel the urge to defecate. A recent study has used colonic manometry to show that these children are aware of the urge to defecate, but that they misinterpret the sensation as abdominal pain.

The researchers analysed data from 56 children who had been diagnosed with functional constipation and denied the urge to defecate. During the manometric test, the first high-amplitude propagating colonic contraction (HAPC) was associated with retentive posturing and facial grimaces. However, when questioned by the examiner the children stated that they felt nothing. The examiner then discussed the readout from the manometric assessment with the child and their caregiver, explaining that the pain was a signal to defecate that would pass if they relaxed and allowed the bowel movement. During subsequent HAPCs, all the children recognized the urge to defecate and successfully defecated.

The authors suggest that functional constipation in these children is the result of learned maladaptive behaviours to avoid a painful or unpleasant experience. “Colon manometry can be a powerful tool for biofeedback and reassurance,” write the authors. “It is an opportunity for the clinician to show the patient and family that the child is healthy, that the condition is not dangerous and that they can get better if they are ready to make an effort to do so.”