Constipation and Encopresis in Childhood

IMPORTANT POINTS

1. Constipation is a symptom, not a diagnosis, that has multiple etiologies and multiple alternative treatments.

2. Encopresis or fecal soiling has many etiologies, not all of which are associated with fecal retention or responsive to laxatives.

3. Children who have Hirschsprung disease almost never have encopresis because the aganglionic segment maintains tonic contraction due to the absence of inhibitory neurons containing nitric acid and vasoactive intestinal polypeptide.

4. Functional retentive constipation is associated with loss of lower colonic muscle tone and will not resolve until complete repetitive evacuation of the lower colon allows muscle tone to be restored.

5. Successful treatment of constipation and encopresis requires a combination of patient and parent education, medical therapy, nutritional intervention, behavioral modification, and long-term monitoring of compliance.

Introduction

Constipation is a very common frustration for children, parents, and physicians. It is reported to account for nearly 5% of all outpatient visits to pediatric clinics and more than 25% of all referrals to pediatric gastroenterologists. Painful defecation and encopresis (involuntary passage of stool from the anus) usually are the first manifestations noted. Constipation generally is defined by the hard nature of the stool, the pain associated with its passage, or the failure to pass three stools per week. It would be preferable to define constipation as the failure to evacuate the lower colon completely with a bowel movement. This allows the parents and physician to realize that a child who has three small stools daily may not yet have evacuated the colon, while a child who has two large soft stools a week may not be constipated.

The frequency of stools in most children decreases from a mean of four per day in the first week of life to 1.7 per day by the age of 2 years. Over this interval, stool volume increases more than tenfold while maintaining …