Anorectal malformation

What are anorectal malformations?

Anorectal malformations are birth defects where the anus and rectum (bottom) do not develop properly. They occur in an around 1 in 4,000 newborn babies and can range from mild to complex.

What type of anorectal malformation does my baby have?

Perineal fistula or rectoperineal fistula

Perineal fistula is the simplest problem. It is where the bowel opens out on to the skin, but the opening is not within the muscles that allow people to control their bowels. These can happen in boys and girls.

Perineal fistula

Rectoperineal fistula

Anorectal malformations without an opening to the bottom

Some babies do not have an opening to the bottom at all. They will have connection to the urinary system (waterworks) which is called a rectourethral, rectoprostatic or rectobladder neck fistula depending on where the connection is.

Rectourethral fistula

Rectoprostatic fistula

Rectobladderneck fistula

Other anorectal malformations in girls

In girls, 2 other types of anorectal malformation can happen.

In a rectovestibular fistula, the bowel opens just outside the vagina and there is no opening on to the bottom.

Rectovestibular fistula

In a cloaca the urethra (tube from the bladder), the vagina and the bowel all open into a common passage.

Cloacal malformation

What will happen after my baby is born?

In the first few days after your baby has been born, our main concern will be seeing if their bowel is blocked.

If it is, we will need to make a colostomy (taking part of the colon up to the skin for the temporary passage of poo). Occasionally it may be possible to correct the problem straight away. If this is the possible your surgeon will discuss it with you.

We will also need to look for other problems which may be related. There might be:

• a spine problem
• heart problems
• a condition called oesophageal atresia
• kidney and peeing problems
• arm or leg problems

Some of these problems are obvious and we do scans to detect some of them.

What will happen when my baby comes for anorectal malformation repair?

After we investigated for the other problems that your baby might have, we will start preparing your baby for their surgical repair.

The type of surgery they will have will depend on their problem. Some operations take 1 hour and a half hours while others may take over 3 hours.

The surgery will include giving your baby a general anaesthetic and possibly an epidural. Your baby will have a wound on their bottom and sometimes another wound in the tummy. We usually call this operation a PSARP (posterior saggital anorectoplasty) procedure.

What are the risks of surgery?

The risks of this surgery include:

• infection — so we will give antibiotics to reduce this risk
• bleeding — so a blood transfusion may be necessary
• damaging the nerves that control sexual function
• the wound can open up
• the new opening (called the ‘neoanus’) can start to narrow

In the long-term there is a risk of your baby either having constipation or not being able to control their bowels or their bladder. This risk depends on the type of malformation and your surgeon will discuss this with you.

What will happen after surgery?

After surgery your baby will go to the ward for observation and pain control.

If your baby has a colostomy, feeds can start soon after recovery from general anaesthesia.

Your baby might need a couple of days of antibiotics before going home.

A follow-up appointment will be arranged for you and your baby for the next steps. This will start with dilatation (stretching) their new opening using metal rods. There will also be a plan for closing the colostomy if needed.

What about toilet training?

Most children who are born with an anorectal malformation will have full control of their bowel and bladder although they may need extra help with this.

If the problem was severe, your child might find it more difficult to have complete control and may need to have more surgery or regular bowel washouts to become continent (have control).

Constipation can be a problem for all children who have been born with anorectal malformations. This needs to be treated promptly, usually with laxatives, and a good fluid intake and diet.

Children who have associated bladder problems may also need procedures to help have bladder control. Even when they have full control, it is likely that your child will have to take more care than people who have no bowel problems at all.

Specialist nurses will be able to help support you if your child has a problem with incontinence, toilet training and constipation.