Lower digestive tract problems

There are many problems that may affect the lower digestive tract that require clinical care by a physician or other healthcare professional. Severe constipation, irritable bowel syndrome and encopresis often respond to medical treatment and are discussed in these pages.

Also listed here are some conditions typically treated by a pediatric surgeon (a general surgeon with specialized training in pediatrics).

Hirschsprung disease

Hirschsprung disease occurs when some of the nerve cells that are normally present in the intestine do not form properly while a baby is developing during pregnancy. This lack of nerve cells in the intestine prevents peristalsis, the normal movement of stool through the intestine. Consequently, the intestine can become partially or completely obstructed (blocked), and begins to expand to a larger than normal size.

Intussusception

Intussusception is the most common cause of intestinal obstruction in children between 3 months and 6 years of age. Intussusception occurs when a portion of the intestine folds like a telescope, with one segment slipping inside another segment. This causes an obstruction, preventing the passage of food that is being digested through the intestine.

The walls of the two "telescoped" sections of intestine press on each other, causing irritation and swelling. Eventually, the blood supply to that area is cut off, which can cause damage to the intestine.

Intestinal malrotation/volvulus

Intestinal malrotation is a birth defect involving a malformation of the intestinal tract. It occurs while a fetus is forming in its mothers' uterus. A child with malrotation is likely to experience a twisting of the intestine known as a volvulus.

This will cause an obstruction, preventing food from being digested normally. The blood supply to the twisted part of the intestine can also be cut off, which can lead to the death of that segment of the intestine.

Pyloric stenosis

Pyloric stenosis is a problem that affects babies between 2 and 8 weeks of age and causes forceful vomiting that can lead to dehydration. It is the second most common problem requiring surgery in newborns.

Meckel diverticulum

Meckel diverticulum is a small pouch in the wall of the intestine, near the junction of the small and large intestines. The pouch is a remnant of tissue from the prenatal development of the digestive system. It is not made of the same type of tissue as the small intestine, but, instead, is made of the type of tissue found in the stomach or the pancreas.

The tissue in Meckel diverticulum produces acid, just as the tissue of the stomach does. The intestinal lining is sensitive to being in contact with acid, and eventually an ulcer can form. The ulcer can perforate (rupture), causing waste products from the intestine to leak into the abdomen. A serious abdominal infection called peritonitis can result. The intestine can also become obstructed (blocked) by Meckel diverticulum.