Anal atresia (anorectal malfunction; imperforate anus) is a congenital defect, where the baby is born with the problem of the anus that develops abnormally, meaning the anus developed in the wrong place or is not present at all. Anal atresia is categorized in two distinct forms. Boys can be born with high anal atresia where a fistula (channel) develops and connects the large intestine (colon) to the bladder or urethra where urine passes out the penis from the bladder. Girls can be born with a fistula (channel) from the large intestine to the vagina.
Six out of every ten children born with congenital high anal atresia also suffer from other defects. Some of these problems can include difficulties with the bones, urinary tract, trachea, heart, spleen, kidneys, limbs, or esophagus. However, low anal atresia cases tend to involve a channel that opens in front of a mass of muscles that will constrict the anal sphincter to close in boys and girls, or just below the scrotum in boys. Sometimes, the anus is not present at birth and instead, the end of the large intestine stops just under the skin.
The most common forms of anal atresia include:
- The anal passageway may develop too narrow or in the wrong location.
- The end of the large intestine (rectum) may not develop correctly by connecting to the anus (the opening where the body passes stools from the large intestine).
- A membrane may develop and cover the anal opening.
- The rectum may develop as a part of the reproductive system or urinary tract by way of a fistula (channel), especially when the anus does not develop at all.
Who Is at Risk for Anal Atresia?
Anus and rectum congenital defects occur in approximately one out of every 5000 births. Boys are slightly more at risk for developing the congenital condition compared to girls. Some cases might be inherited. Research indicates that mothers who birth one child with an anus or rectum defect have a one percent increased potential risk of birthing another child who will also suffer from the identical ailment.
However, medical science has yet to determine the exact cause of anal atresia that always develops when the fetus is in the womb.
There are certain complications associated with anal atresia and repair. Some of these complications involve:
- Failure to Thrive – Doctors can determine if the child is failing to thrive by not obtaining optimal weight gain as they mature from infant to toddler. In some cases, the condition can lead to death. Major complications can arise when the infant's formula is mixed with too much water against the manufacturer's instructions. This is because the weakened formula can result in low weight gain or nutrition.
- Acquired Medical Issues – Anal atresia can cause numerous medical issues before or after the child is born including heart defects, cleft lip, infections, or a lack of physical or emotional stimulation.
- Insufficient Support and Care – Many children with anal atresia fail to thrive because of a lack of love and attention. Without constant support, the child can become depressed, leading to the loss of a desire to eat and thrive. All babies, including those with anal atresia, require constant care, eye to eye contact, and nurturing to ensure healthy development.
- One Hospitalization Is Required – When the child requires hospitalization, here she can give up their will to live if they did not receive constant attention, caring and love.
Some research indicates that the mother using steroid inhalers while pregnant could be one of the causes of the child developing anal atresia.
Many children with anal atresia become constipated after the repair and require an ongoing high fiber diet. Many of the common symptoms associated with anal atresia include:
- Malformed Anal Opening – The child may be born with an abnormal opening of the anus that is in the wrong location or not present.
- Failure to Past Stool – The child may not pass stool within the first 24 to 48 hours after being born.
- Stool Passing Problems – The child may be excreting stools through the urethra, scrotum, penis, or vagina.
- Tightened, Swollen Stomach
- Decreased Weight Gain – The child can become easily malnourished causing a decrease in their weight gain. Indicators of malnourishment can be identified if the child is two years or younger and has not gained weight each month since birth.
- Poor Physical Development – The child might be slow to develop when crawling, walking, rolling over, or talking at the appropriate age.
- Poor Eating Habits – The child might have poor feeding habits, sleep disturbances, unexplained vomiting, or is constantly spitting up food.
- Loss of Appetite – The child may have a loss or decrease of appetite, leading to all types of serious health problems.
- Repetitive Negative Behaviors – The child may develop repetitive behaviors including rocking their body or banging their head, indicating that more stimulation is required.
Diagnosing Anal Atresia
Anal atresia is easy to diagnose during a physical examination once the child was born. However, determining the extent of the damage usually requires other procedures and tests including x-rays to see what parts of the body have developed abnormally.
Medical science has determined that the child's intestines develop in the wound during the fifth to seventh week of pregnancy. Scientists believe that any disturbance occurring to the fetus during this phase of development could lead to anal atresia. However, the exact reason or risk factor has not yet been identified.
Treating the Condition
Nearly all forms of anal atresia will require one or more surgical procedures to correct the condition. After surgery, the child will likely require anal dilations to ensure the anus enlarges gradually as the patient matures.
Many children who have undergone an anal treatment repair become constipated, necessitating the consumption of a high-fiber diet and likely the use of laxatives and the time before they are fully "potty" trained. That said, many children with the condition are toilet trained successfully at the appropriate time of maturation. Over time, the child will likely gain better bowel control. However, the process is slow. Depending on the malformation of the anus and rectum, and the type of surgical repair, the child may not ever achieve optimal bowel control.
Surgical treatments are available for anal atresia. In cases involving high anal atresia, the surgeon will perform a colostomy, where an incision in the large intestine (colon) is made to create a temporary opening in the abdomen to allow the excretion of waste. Within a few months, the surgeon will then move the intestine to the sphincter ring of muscles and close the colostomy opening weeks later.
When surgically repairing low anal atresia, the surgeon will make a hole in the skin where the anus should be and move the intestine into the correct position in subsequent surgeries. As the child matures, the pediatric surgeon will widen or dilate the rectum using an instrument, and teach the parents to perform the procedure each day at home to prevent the development of scar tissue caused by skin contractions.
Medical science has yet to determine a way to prevent the development of anal atresia.