Imperforate anus may include a single abnormality or a combination of abnormalities of the rectum (the end of the intestine near the anus) and anus (the opening of the rectum to the skin). There are many forms of this birth defect that may include the following:
- The absence of an anal opening, which prevents any bowel movements completely.
- The anal opening in the wrong place that is often too small.
- A connection, or opening called a fistula, between the rectum and the urethra, bladder or vagina. This may cause bowel movements to pass out of these abnormal openings.
- In girls, the rectum, urethra, vagina can join together to form a single opening. This is called a cloaca and it is very rare.
There is no known cause for imperforate anus and most cases are isolated and do not run in families. The birth defect occurs in about one of every 4,000-5,000 newborns and is somewhat more common in boys than girls.
- What are symptoms of imperforate anus?
- How is the diagnosis of imperforate anus made?
- What is the treatment for imperforate anus?
- How long will my child be in the hospital after the operation?
- Homecare after imperforate anus repair
What are symptoms of imperforate anus?
If the opening of the anus is missing the baby will not be able to pass stool after birth. Because the intestine ends in a blind pouch, instead of opening to the skin, baby stool (called meconium) is retained in the intestine. This can cause vomiting and a swollen or "enlarged" abdomen.The type of anatomic abnormality can vary, and it is important for you to understand your child's anatomy after birth. The portion of the intestine called the rectum can end high in the abdomen, far away from the skin, or it can end low or very close to the skin.
If there is a connection between the intestine and the urethra (the tube that drains the bladder) or the bladder itself, stool may be passed with the baby's urine. If there is a connection between the intestine and the vagina, meconium may pass out of the vagina.
How is the diagnosis of imperforate anus made?
If the anal opening is missing or in the wrong place, it can be seen on a physical examination. If there is stool coming out of the urethra or vagina, it will be seen as the baby passes urine. Some newborns with imperforate anus have other health associated problems.
What is the treatment for imperforate anus?
Since the anatomy varies in imperforate anus patients, the surgical plan will be determined by your child's individual needs. In some newborns, if the anus is low in the pelvis, the rectum can be pulled down to the anus and a new opening created in a single operation. In this case, a stoma is not necessary and the entire defect is repaired at one operation.
If the anal opening is misplaced, it will be closed and a new anal opening will be made in the correct place. This operation is called an anoplasty and is performed soon after birth. An anoplasty is usually done in one stage or a single operation.
If the anus is missing, an operation will be needed to make an opening for stool to pass. When the intestine ends high in the pelvis (the area below the abdomen, between the hips), surgical repair will require multiple stages. First a stoma, or connection of the intestine to the abdomen, is created. In the second operation, the rectum is pulled down to the anus where an anal opening is created and the intestine attached. During the operation, if there is a (fistula) connection between the urethra, bladder or vagina, and the rectum it will be closed to prevent stool from entering that area. The stoma is closed in a third operation, several months later, after the new anal opening has been dilated and is healed.
In most imperforate anus operations, there is very little blood loss. You child will receive blood only in the rare case of an extreme emergency. If you wish to provide a directed donation of blood, contact our office, 1-2 weeks in advance of the operation.
How long will my child be in the hospital after the operation?
Children can go home once they are feeding normally, having bowel movements, are comfortable on pain medication by mouth and do not have a fever. Babies who have this operation, without a stoma, often have very frequent bowel movements that can cause severe diaper rash. We will begin using a protective skin cream as soon as bowel movements start. This cream is to be applied after each bowel movement and with each diaper change. Use thickly to protect the skin from the irritating effects of the stool. We recommend you continue this cream at home, for several weeks, until the number of stools passed each day become less frequent.
Newborns that have a stoma made will need a special pouch placed on the abdomen, over the stoma, to catch the stool. Your baby's nurses will explain how the pouchs are applied and removed. The surgical nurse practitioner will order stoma bags for your child to be sent to your home after hospital discharge. You will use the pouchs at home until the stoma is closed.