Esophageal atresia

Definition

Esophageal atresia is a serious birth defect in which the esophagus, the long tube that connects the mouth to the stomach, is segmented and closed off at any point. This condition usually occurs with tracheoesophageal fistula, a condition in which the esophagus is improperly attached to the trachea, the nearby tube that connects the nasal area to the lungs. Esophageal atresia occurs in approximately 1 in 4,000 live births.

Description

Failure of an unborn child (fetus) to develop properly results in birth defects. Many of these defects involve organs that do not function, or function only incidentally, before birth, and, as a result, go undetected until the baby is born. In this case, the digestive tract is unnecessary for fetal growth, since all nutrition comes from the mother through the placenta and umbilical cord.

During fetal development, the esophagus and the trachea arise from the same original tissue. Normally, the two tubes would form separately (differentiate); however, in cases of esphageal atresia and tracheoesophageal fistulas, they do not, resulting in various malformed configurations. The most common configuration is the "C" type, in which the upper part of the esophagus abruptly ends in a blind pouch, while the lower part attaches itself to the trachea. This configuration occurs in 85-90% of cases. Esophageal atresia without involvement of the trachea occurs in only 8% of cases.

Causes & symptoms

The cause of esophageal atresia, like that of most birth defects, is unknown.

An infant born with this defect will at first appear all right, swallowing normally. However, the blind pouch will begin to fill with mucus and saliva that would normally pass through the esophagus to the stomach. These secretions back up into the mouth and nasal area, causing the baby to drool excessively. When fed, the baby will also immediately regurgitate what he or she has eaten. Choking and coughing may also occur as the baby breaths in the fluid backing up from the esophagus. Aspiration pneumonia, an infection of the respiratory system caused by inhalation of the contents of the digestive tract, may also develop.

Diagnosis

Physicians who suspect esophageal atresia after being presented with the above symptoms diagnose the condition using x-ray imaging or by passing a catheter through the nose and into the esophagus. Esophageal atresia is indicated if the catheter hits an obstruction 4-5 in (10-13 cm) from the nostrils.

Treatment

Infants with esophageal atresia are unlikely to survive without surgery to reconnect the esophagus. The procedure is done as soon as possible; however, prematurity, the presence of other birth defects, or complications of apiration pneumonia may delay surgery. Once diagnosed, the baby will be fed intraveneously until he or she has recovered sufficiently from the operation. Mucus and saliva will also be continuously removed via a catheter until recovery has occured. When surgery is performed, the esophagus is reconnected and, if neccessary, separated from the trachea. If the two ends of the esophagus are too far apart to be reattached, tissue from the large intestine is used to join them.

Prognosis

Surgery to correct esophageal atresia is usually successful. Post-operative complications may include difficulty swallowing, since the esophagus may not contract efficiently, and gastrointestinal reflux, in which the acidic contents of stomach back up into the lower part of the esophagus, possibly causing ulcers.

Key Terms

Fetal

Refers to the fetus, also known in the first two months after conception as an embryo.

Fistula

Unnatural connection between two hollow organs or one organ and the outside.

Further Reading

For Your Information

Books

• "Atresia and Tracheoesophageal Fistula." Nelson Textbook of Pediatrics, edited by Waldo E. Nelson, et al. Philadelphia: W. B. Saunders, 1996.
• Long, John D., and Roy Orlando. "Anatomy and Development and Acquired Anomalies of the Esophagus." Sleisenger & Fordtran's Gastrointestinal and Liver Disease, edited by Mark Feldman, et al. Philadelphia: W. B. Saunders, 1998.

Gale Encyclopedia of Medicine. Gale Research, 1999.