CHILDREN CONSTIPATION FUNCTIONAL

A normal pattern of stool evacuation is felt to be a sign of health in children of all ages. Especially during the first months of life, parents pay close attention to the frequency and the characteristics of their children’s defecation. Any deviation from what is felt to be normal for children by any family member may trigger a call to the nurse or a visit to the pediatrician. Thus, it is not surprising that approximately 3% of general pediatric outpatient visits and 25% of pediatric gastroenterology consultations are related to a complaint of defecation disorder.

Chronic constipation is a source of anxiety for parents who worry that a serious disease may be causing the symptom. Yet only a small minority of children have an organic etiology for constipation. Beyond the neonatal period, the most common cause of constipation is functional constipation, which has also been called idiopathic constipation, functional fecal retention, and withholding constipation. In most cases the parents are worried that the child’s stools are too large, too hard, painful or too infrequent. The normal frequency of bowel movements at different ages has been defined.

Infants have a mean of 4 stools per day during the first week of life. This frequency gradually declines to a mean average of 1.7 stools per day at 2 years of age and 1.2 stools per day at 4 years of age. Some normal breastfed babies do not have stools for several days or longer. After 4 years, the frequency of bowel movements remains unchanged.

In most children constipation is functional, that is, without objective evidence of a pathological condition. Functional constipation most commonly is due to painful bowel movements with resultant voluntary withholding of feces by a child who wishes to avoid an unpleasant defecation.

Many events can lead to painful defecation such as toilet training, changes in routine or diet, stressful events, intercurrent illness, unavailability of toilets, or postponing defecation because the child is too busy. They can lead to prolonged fecal stasis in the colon, with reabsorption of fluids and an increase in the size and consistency of the stools.

The passage of large hard stools that painfully stretch the anusmay frighten the child, resulting in a fearful determination to avoid all defecation. Such children respond to the urge to defecate by contracting their anal sphincter and gluteal muscles, attempting to withhold stool. They rise on their toes and rock back and forth while stiffening their buttocks and legs, or wriggle, fidget or assume unusual postures, often performed while hiding in a corner. This dancelike behavior is frequently misconstrued by parents who believe that the child is straining in an attempt to defecate.

Eventually, the rectum habituates to the stimulus of the enlarging fecal mass and the urge to defecate subsides. With time such retentive behavior becomes an automatic reaction. As the rectal wall stretches fecal soiling may occur, angering the parents and frightening the child. After several days without a bowel movement, irritability, abdominal distension, cramps and decreased oral intake may result.