Encopresis is the soiling of underwear with stool by children who are past the age of toilet training. Because each child achieves bowel control at his or her own rate, medical professionals do not consider stool soiling to be a medical condition unless the child is at least 4 years old. This stool or fecal soiling usually has a physical origin and is involuntary -- the child doesn't do it on purpose.
In the U.S., it is estimated that 1%-2% of children younger than 10 years are affected by encopresis. Many more boys than girls experience encopresis; approximately 80% of affected children are boys.
Rarely, encopresis is caused by an anatomic abnormality or disease that the child is born with. In the great majority of cases, encopresis develops as a result of chronic (long-standing) constipation.
What is constipation? Many people think of constipation as not passing a bowel movement every day. However, each person has his or her own schedule for bowel movements, and many healthy people do not have a bowel movement every day. A constipated child might pass a bowel movement every third day or less often. Constipation implies not only infrequent bowel movements, but also having difficulty or experiencing pain when doing so.
In most children with encopresis, the problem begins with painfully passing very large stools. This may have happened long before the encopresis starts, and the child may not remember this when asked. Over time, the child becomes reluctant to pass bowel movements and holds it in to avoid the pain. This “holding in” becomes a habit that often remains long after the constipation or pain with passing bowel movements has resolved.
As more and more stool collects in the child’s lower intestine (colon), the colon slowly stretches (sometimes called megacolon).
As the colon stretches more and more, the child loses the natural urge to pass a bowel movement.
Eventually, looser, partly formed stool from higher up in the intestine leaks around the large collection of harder, more formed stool at the bottom of the colon (rectum) and then leaks out of the anus (the opening from the rectum to the outside of the body).
Often in the beginning, only small amounts of stool leak out, producing streaks in the child’s underwear. Typically, parents assume the child isn’t wiping very well after passing a bowel movement and aren't concerned.
As time goes on, the child is less and less able to hold the stool in-more and more stool leaks, and eventually the child passes entire bowel movements into his or her underwear.
Often the child is not aware that he or she has passed a bowel movement.
Because the stool is not passing normally through the colon, it often becomes very dark and sticky and may have a very foul smell.