Achalasia

What Is It?

Achalasia is an uncommon disorder of the smooth muscle of the esophagus, the muscular tube that extends from the mouth to the stomach. Normally, coordinated contractions of this smooth muscle, known as peristaltic waves, carry food into the stomach. Between the esophagus and stomach is a special muscle called the esophageal sphincter (LES) that surrounds the esophagus to keep it closed and prevent food and acid from splashing back up into the esophagus from the stomach. When you swallow, this sphincter relaxes and opens to allow food to pass into the stomach. When you swallow, nerves tell the muscles when to contract so that the contractions of the esophagus are coordinated with the relaxation and opening of the LES. In achalasia, the nerve cells in the lower two-thirds of the esophagus and LES are abnormal. This causes uncoordinated or weak peristaltic waves and causes the LES to remain closed, making it difficult for food to pass from the esophagus into the stomach.

The cause of achalasia is unknown. Studies show that there is degeneration and damage of the nerves that control the muscle contractions of the esophagus. The cause of the degeneration is unclear. There have been theories that a viral infection leads to nerve damage but these theories have not been proven. Another possibility is that the body's immune system attacks and destroys the nerves. Approximately 2,000 new cases of achalasia are diagnosed each year in the United States.

Other conditions besides achalasia can cause the esophagus to function improperly, including diffuse esophageal spasm, polymyositis or dermatomyositis, hypothyroidism and scleroderma esophagus.

Symptoms

Most people with achalasia develop symptoms between the ages of 25 and 60, but the condition can occur in children. It does not run in families. The symptoms come on gradually and may take years to progress. Symptoms can include:

• Difficulty swallowing solid food (swallowing liquids is not affected in the early stages)
• Regurgitation or vomiting of undigested food
• Chest pain, discomfort, or fullness under the breastbone, especially following meals
• Coughing, especially at night or when lying down
• Difficulty swallowing solids and liquids (late in the illness)
• Weight loss (late in the illness)

Diagnosis

Among the tests that may be needed to diagnose achalasia and rule out other conditions are the following:

• Esophagography (barium swallow) — You will swallow a thick liquid (barium) that can be seen on an X-ray. The test can show whether the esophagus is enlarged or dilated, and whether the barium is able to empty properly into the stomach. The study is generally painless, although some people experience the same discomfort they may have when swallowing foods or liquids.