Achalasia is a disorder in which the lower esophageal sphincter does not relax when food passes down the esophagus to the stomach. As a result, the esophagus becomes distended and filled with food, and food passes into the stomach very slowly. Achalasia is often associated with chest pain during eating, weight loss, and regurgitation of food. The lower esophagus becomes distended as food and liquid are unable to pass into the stomach

INTRODUCTION — Achalasia is a rare swallowing disorder that affects only 1 in every 100,000 people. Patients typically first note increasing difficulty swallowing. Most people are diagnosed between the ages of 25 and 60 years. It is usually a chronic condition that worsens over time and does not resolve.

Several different treatments are available. Each treatment has advantages and disadvantages. It is important to discuss the various treatment options with your doctor before making a decision.

CAUSE — The specific cause of achalasia is unknown. However, patients with achalasia have two problems in the esophagus (the tube which carries food from the mouth to the stomach).

• The first is that the lower two-thirds of the esophagus does not propel food toward the stomach properly.

• The second problem is in the lower esophageal sphincter (LES), a circular band of muscle that lies at the junction of the esophagus and the stomach. The LES normally helps prevent food from flowing backwards, from the stomach into the esophagus. The LES should relax in response to swallowing to allow food to enter the stomach. In patients with achalasia, the LES fails to relax, creating a barrier that prevents food and liquids from passing into the stomach. One theory about achalasia is that the nerve cells responsible for relaxation are destroyed by an unknown cause.

Damage to the LES and esophagus causes large volumes of food and saliva to accumulate in the esophagus. Patients can initially compensate for this but eventually the barrier progresses to the point where food and saliva cannot reliably enter the stomach, and, as a result, build up in the esophagus.

SYMPTOMS — The symptoms have a slow onset and progress gradually; many people delay seeking medical attention until symptoms are advanced. The major symptom is difficulty swallowing (liquids or solids). Other symptoms include chest pain, regurgitation of swallowed food and liquid, heartburn, difficulty burping, a sensation of fullness or a lump in the throat, hiccups, and weight loss.

DIAGNOSIS — Achalasia is usually suspected based upon the presence of the symptoms described above, but tests are needed to confirm the diagnosis. In addition, it is important to rule out other conditions with similar symptoms, such as gastroesophageal reflux disease, pseudoachalasia (a rare condition in which certain tumors can mimic the features of achalasia), and an infection called Chagas' disease, which is seen almost exclusively in Central and South America.

Chest x-rays — A simple chest x-ray may reveal distortion of the esophagus and absence of air in the stomach, two abnormalities that suggest achalasia.

Barium swallow test — The barium swallow test is the primary screening test for achalasia. The test involves swallowing a chalky-tasting, thick mixture of barium while x-rays are taken. The barium shows the outline of the esophagus and LES .

Barium swallows are usually performed under fluoroscopy, a continuous low-grade x-ray, which is helpful for studying the motion in the esophagus. In achalasia, barium swallows usually reveals an absence of contractions in the esophagus after swallowing. Sometimes this test reveals spastic contractions of the esophagus in response to swallowing; this variation of achalasia is known as vigorous achalasia.

After the barium swallow, patients should drink extra fluid. Stools may be light in color for a few days after testing as a result of the barium.

Manometry — Manometry refers to the measurement of pressure within the esophagus and the LES. Pressures are measured by advancing a thin tube through the mouth or nose into the esophagus. The test is done after patients have had nothing to eat or drink for eight hours, while patients are awake. Patients will be asked to swallow while the tube is in place.

Manometry is always used to confirm achalasia. The test typically reveals three abnormalities in people with achalasia: high pressure in the LES at rest, failure of the LES to relax after swallowing, and an absence of useful (peristaltic) contractions in the lower esophagus. The last two features are the most important and are required to make the diagnosis.

Endoscopy — Endoscopy allows for direct visualization of the inside of the esophagus, LES, and stomach using a thin, lighted, flexible tube. Endoscopy is done while a patient is sedated. This test is usually recommended for people with suspected achalasia and is especially useful for detecting other conditions that mimic achalasia.

In people with achalasia, endoscopy often reveals distortion of the esophagus and the presence of residual food; it may also reveal inflammation, small ulcers caused by residual food or pills, and candida (yeast) infection. The endoscope can be advanced through the LES and into the stomach to check for stomach cancer. Cancer in the upper part of the stomach can produce symptoms almost identical to those of achalasia, and is called pseudoachalasia (meaning "false" achalasia). Thus, biopsies (small samples of tissue) are often obtained in the lower portion of the esophagus. Having a biopsy while sedated is not painful and is very safe.

TREATMENT — Several options are available for the treatment of achalasia. Unfortunately, none can halt or reverse the underlying problem. However, all of the treatments are effective for improving symptoms.

Two of these treatments (drug therapy and botulinum toxin injection) work by reducing the LES pressure while two other treatments (balloon dilatation and surgery (myotomy)) work by mechanically weakening the muscle fibers of the LES.

Drug therapy — Two classes of drugs, nitrates and calcium channel blockers have muscle-relaxing effects. These drugs can relax the LES and decrease symptoms in people with achalasia. They are usually taken by placing a pill under the tongue 10 to 30 minutes before meals.

Drug therapy is the least invasive option for treating achalasia. However, most people find that long-term drug therapy is inconvenient, ineffective, and sometimes associated with side effects such as headache and low blood pressure. Furthermore, these drugs tend to lose their effectiveness over time. For these reasons, medications are recommended for patients who are not interested in or not healthy enough for other treatments.

Balloon dilatation (pneumatic dilatation) — Balloon dilatation mechanically stretches the contracted LES. This procedure is effective for relieving symptoms of achalasia in two-thirds of patients, although chest pain persists in some people. Up to half of patients may require more than one treatment for adequate relief. Patients receive general anesthesia and are generally able to go home at the end of the day.

  Procedure — People undergoing balloon dilatation are typically placed on a liquid diet 12 hours to two days in advance (a longer period is recommended in patients with a great deal of food in the esophagus). Using fluoroscopy, a physician advances a guide wire down the esophagus and positions it inside the LES. A deflated balloon is then advanced along this guide wire, positioned inside the LES, and inflated for about 60 seconds. The balloon is then deflated and withdrawn, and the person is monitored in a recovery area for five to six hours to detect any complications of the procedure. If there are no complications, people can usually resume eating after six hours. If a person's day-to-day symptoms do not improve, additional sessions can be performed.

  Success rate — A single balloon dilatation session continues to relieve symptoms of achalasia in about 60 percent of people one year after the procedure and in about 25 percent of people five years after the procedure. Higher success rates have been reported in some studies. The success rate at later time points has not been well studied, but some people have remained symptom-free for as long as 25 years.

  Complications — About 15 percent of people experience severe chest pain immediately after balloon dilatation, and some experience fever.

The most significant complication of balloon dilatation is creation of a hole (perforation) in the wall of the esophagus; this complication occurs in about 2 to 6 percent of people undergoing the procedure, and it is most likely to occur during the first dilatation session. Symptoms of persistent or worsening pain in the hours after the procedure may indicate a perforation. Some doctors routinely check x-ray and/or swallow tests immediately after the procedure to check for a perforation.

Most perforations are small, and some heal on their own with antibiotics and intravenous feeding. However, many doctors recommend surgery to repair these tears, regardless of their size. There is no way to predict perforation; however, it is sensible to choose a doctor who has a great deal of experience performing balloon dilatation procedures.

Other possible complications of balloon dilatation include bruising of the esophageal wall, damage to the esophageal lining, the development of small pockets (diverticula) in the esophagus or upper stomach, and the development of gastroesophageal reflux disease (GERD). Because the LES is the principal barrier which prevents the reflux of stomach contents into the esophagus, its disruption can lead to acid reflux. GERD occurs in about 2 percent of people after balloon dilatation, but is usually easily controlled with acid-reducing medications.

Surgery (myotomy) — Myotomy can be used to directly cut the muscle fibers of the LES. The surgical technique used most often is called the Heller myotomy. In the past, surgery was performed through an open incision in the chest or abdomen, but it can now be performed through a tiny incision using a thin, lighted tube (a laparoscope or a thoracoscope). This new approach is less traumatic and shortens recovery time. Patients who undergo myotomy are given general anesthesia, and generally stay in the hospital for one to two nights.

  Success rate — Surgery relieves symptoms in 70 to 90 percent of people. Symptom relief is sustained in about 85 percent of people 10 years after surgery and in about 65 percent of people 20 years after the surgery. Thus, surgery is a more permanent solution for achalasia than balloon dilatation or botulinum toxin injection (see below). However, surgery can also be associated with complications, is more invasive than balloon dilatation (and more costly).

  Complications — Like balloon dilatation, there is a risk of reflux following myotomy, which, over time, can cause damage to the esophagus. Surgeons generally perform a fundoplication (wrapping a portion of the stomach around the esophagus to prevent regurgitation of stomach contents) at the time of surgery; however this does not always prevent reflux. Patients should be regularly monitored for this complication, and may require acid suppressing medications. The procedure requires general anesthesia, and patients are hospitalized for one to two days . Some post-operative pain is expected, which can be controlled with pain medications.

Botulinum toxin injection — Botulinum toxin injection is the newest treatment for achalasia. The botulinum toxin temporarily paralyzes the nerve cells that signal the LES to contract thereby helping to relieve the obstruction. Botulinum toxin injection may also be used as a diagnostic test in people with suspected achalasia who have inconclusive test results.

  Procedure — The injection procedure is performed during routine endoscopy, while patients are sedated. The botulinum toxin is injected directly into the LES.

  Success rate — A single botulinum toxin injection session relieves symptoms in 65 to 90 percent of people in the short term (three months to approximately one year). Additional injections can relieve symptoms in patients whose symptoms return. Botulinum toxin injection is more likely to be effective in people over the age of 50 years and in people who have the vigorous form of achalasia.

When compared with balloon dilatation, botulinum toxin has a similar effectiveness for relieving symptoms in the first one to two years after the procedure; however, this prolonged effectiveness requires multiple botulinum toxin injections in 40 to 50 percent of people. The long-term safety and effectiveness of botulinum toxin injection is unknown.

  Complications — About 25 percent of people have chest pain for a few hours after the procedure while about 5 percent develop heartburn. Damage of the esophageal wall and lining are rare. The short-term safety of botulinum toxin injection appears to be greater than the short-term safety of both balloon dilatation and surgery; this greater short-term safety may make botulinum toxin injection a better choice for people with other medical conditions who must avoid more invasive procedures. Because the amounts of botulinum toxin used are very small, there is virtually no risk of botulism poisoning from this procedure.

LONG-TERM RISK OF ESOPHAGEAL CANCER — People with achalasia have an increased risk of esophageal cancer, particularly if obstruction is not adequately relieved. As a result, doctors recommend regular endoscopic screening for early detection of this cancer.

WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two patients are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.

This discussion will be updated as needed every four months on our web site . Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information. Some of the most pertinent include:

A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable.

• National Library of Medicine