Imperforate Anus
Imperforate Anus: What is it?
Your child has been born with an Imperforate Anus. The anus is the opening where the bowel connects to the outside of the body. A child born with an imperforate anus does not have the opening or exit for the bowel. This defect has been recognized for centuries. Newborns with this are diagnosed by the inability to pass meconium, or meconium seen in the urine, and during the physical exam there is noted to be little or no opening at the anus.
How many children have Imperforate Anus? Imperforate anus occurs in one out of every 4,000- 5,000 live births. It is slightly more common in males and males are twice as likely to have a high defect than are females.
What causes an Imperforate Anus?
During fetal life, the genitourinary tract and rectum form as one channel. This channel then divides to form each system. For some unknown reason in children with an imperforate anus this division is not complete and the bowel stops before it exits the body at the anus. Bowel contents cannot pass out through the anus. There are varying degrees of severity with this defect. The severity is determined by the distance between the end of the bowel and where the anus should be. The defect may be referred to as a low, intermediate, or high defect. In addition, many children have connections from the bowel to the urinary tract, genitalia, or to the skin. These small connections are called fistulas and will be repaired when your child has this defect repaired. Imperforate anus may occur as an isolated defect, but it may be associated with vertebral, tracheal, esophageal, cardiac, renal, or arm anomalies. Your baby will be examined for the associated defects. You may hear the combination of defects referred to as the VATER or VACTERL association.
Most parents do not know of any relatives with an imperforate anus. Nothing you did brought on this defect. Painting a room while pregnant, taking an aspirin, or going to an aerobics class did not cause your child to have an imperforate anus. It happened regardless of anything you did or did not do. The risk of having a second child with an imperforate anus is approximately 1%.
What will be done for my child?
The diagnosis of imperforate anus will be confirmed by an exam and x-ray films.
The severity of the defect will determine what approach is taken with your child. Children with an anal stenosis, which is the very mildest form of an imperforate anus, will need to have their anus stretched with a dilator. You will be taught to do this before your child is discharged from the hospital.
A child with a low imperforate anus, where the end of the bowel is just inside and very close to the skin, will need an operation to create an opening for the bowel to exit the body. This operation is called an anoplasty. If your child has an intermediate or high defect they will require a temporary colostomy. This is a surgically created opening that allows the stool to exit the body through the abdominal wall. The opening is called a stoma and is red or pink in color. The bowel movements will pass out through the stoma. A pouch, that adheres to your child’s skin, will sit over the stoma and collect the stool. An ostomy nurse will work with you before your child’s discharge from the hospital to teach you how to care for the ostomy.
The colostomy will not bother your baby. Once you have changed the ostomy pouch a few times, you will find yourself quite comfortable with the process. When your child weighs about 20 pounds, at around 1 year old, a pull through procedure will be done to bring the bowel down to and exit through a newly created anus. If your child has a fistula, it will be removed during this surgery. After your child’s surgery, you will need to learn how to stretch the new anal opening with a dilator. The surgeon and nurse will teach you how to do this at one of your child’s post-operative clinic visits. When the new anus has been stretched to the appropriate size, surgery will be done to close the colostomy.
What continuing care will my child need?
It is important to continue follow-up visits with your surgeon so progress may be monitored. Your child will also be seen by a pediatric gastroenterologist. In addition to these specialists, your child needs regular checkups with the pediatrician or family practice doctor in your community.
The long term outcome depends in part on the severity of the defect. Children with a low imperforate anus who have had an anoplasty may have problems with constipation. This can vary from mild to quite severe. Constipation is usually managed with dietary changes or by using mineral oil or occasional suppositories.
Children with high defects have a harder time achieving bowel control after the anal defect is repaired. For a while after the pull through procedure, your child will probably have frequent, loose bowel movements. A small amount of stool may be seen in the diaper all the time. It is important to maintain good skin care in the anal area to prevent painful rashes.
Families with children with high defects usually manage their child's bowel habits by manipulating the child's diet and using enema routines to achieve continence. Determining a routine that is the best for your child takes time and patience. Your child's doctors and nurses will help you find a routine that works best for your child.
Can my child be potty trained?
Most children with low defects eventually potty train without difficulty. Most of the children will potty train for urine before they will be trained for stool. Children with more severe defects often have poor bowel control and frequent accidents. Dietary changes, timing of meals, and a bowel management routine will help your child learn bowel control. Your child's doctors and nurses are available to help you work out a plan for your child.
Glossary
Abdominal distention: The belly becomes firm, round, and appears to stick out - caused by a swelling in the intestines due to large amounts of gas and fluid.
Adhesions: Scars that form on the inside of the abdomen after surgery. Anastamosis, Intestinal: Reattachment of two portions of bowel.
Anomaly: A departure from the normal form.
Anus: The opening of the rectum.
Genitalia: The reproductive organs. Imperforate: Without a normal opening or hole.
Meconium: The thick, sticky green/black first bowel movement a newborn passes.
Motility: Spontaneous movement.
Revised - 6/3/04
