Anorectal malformation (anal atresia) is a congenital abnormality. It refers to conditions where the normal connection between the rectum (the last part of the large intestine) and the anus (the opening at the end of the digestive tract) fails to develop. This condition usually becomes apparent at birth and affects the child’s digestive system functions. It often presents as a closed or absent anus where it should normally be, but there are also types where the anus is narrower or located more anteriorly than normal. This condition can lead to failure to pass stool in the first days of life, and in infants with delayed diagnosis or inappropriate surgical intervention, it can cause bowel perforation.

Anorectal malformation is a rare congenital anomaly in children. It occurs approximately in 1 out of every 5,000 births. It is more common in male infants than in females. The diagnosis is typically made immediately after birth.

Symptoms

Usually detected either during detailed prenatal ultrasounds or immediately after birth. These symptoms include:

• Absence or improper placement of the anus, or complete lack of an opening in that region,
• Feeding difficulties,
• Inability to pass stool,
• Abdominal distension,
• Vomiting and fever.

Since the infant cannot empty the bowels, feeding becomes difficult, and vomiting begins.

Anorectal malformations are classified into several types, primarily divided into low and high types according to severity.

• Low types: The anus is slightly displaced forward. If there is no opening, it is located just slightly above where the anus should be.
• High types: The distal large intestine ends farther away from the normal anal opening site. This is a more serious condition.

Another classification divides anorectal malformations into fistulous and non-fistulous types. When the large intestine is connected to the urinary tract, it is called fistulous anorectal malformation. Those without urinary tract connection are non-fistulous. Fistulous types require urgent surgical intervention in the first hours of life. Without treatment, life-threatening urinary tract infections and kidney loss may occur.

The initial intervention for fistulous anorectal malformations usually involves creating a temporary colostomy (bringing the large intestine out to the abdomen) to protect the urinary tract from contact with stool. After a few months, surgery is performed to reposition the large intestine to the normal anal site, followed by closure of the colostomy, restoring normal anatomy.

Repair of anal atresia is done either via PSARP (Posterior Sagittal Anorectoplasty), involving an incision behind the anus, or by laparoscopic (minimally invasive) surgery, depending on the severity and presence of fistula.

Treatment

Common issues after treatment are constipation and difficulties with stool control. Untreated children may have trouble passing and holding stool because the anal opening and the muscle fibers responsible for controlling defecation are not properly developed or positioned. In cases of high-level anorectal malformations, these problems may persist after surgery due to congenital underdevelopment of these muscle fibers. Therefore, postoperative muscle-strengthening exercises are essential. A regular bowel management program should be implemented. Since not all centers offer this care, patients must be followed and treated in experienced centers with neonatal intensive care units and pediatric surgery departments.

After surgery, infants are usually monitored in the hospital for several weeks. Intravenous fluids and antibiotics are administered until feeding and fluid balance stabilize.

Anorectal malformation is a serious congenital anomaly in children that requires surgical treatment. Early diagnosis and appropriate intervention enable the child to grow and develop healthily. Careful postoperative monitoring and care reduce the risk of complications.

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