Achalasia

What is Achalasia?

Achalasia is a disorder of the oesophagus (the tube that carries food from the mouth to the stomach). The oesophagus is less able to move food toward the stomach and the valve from the oesophagus to the stomach does not relax as much as it needs to during swallowing. This relaxation is needed to allow food to enter the stomach. To the right is a picture of the gastroesophageal junction valve between the stomach and the oesophagus that usually relaxes to allow the passage of food, and then closes so that food cannot 'reflux' back out. As seen in this image (taken with an endoscope - a camera that looks down the throat) the sphincter is very tightly closed and thus would not adequately allow the passage of food.

Statistics on Achalasia?

It affects men and women equally between the ages of 30-60. It can also occur in infancy and childhood. The incidence is 1 in 100,000/year.

Risk Factors for Achalasia

Most commonly the cause is unknown (idiopathic). However, Achalasia can also develop as a result of damage to the nerves to the oesophagus. This is seen in chronic Chagas disease - a condition common in South America which is caused by the Trypanosoma cruzi parasite.

Progression of Achalasia

Achalasia is a progressive disease meaning patients will gradually develop increasing severity of difficulty when swallowing. Medical treatment may alleviate symptoms but they do not provide a long term solution. Most patients require surgical intervention. Those who are treated early (before marked dilation) may avoid complications of oesophageal ulceration, oesophageal candidiasis, and aspirating stomach contents into the lung. There is also a slight increase in the risk of oesophageal carcinoma (cancer of the oesophagus). With successful myotomy (surgery dividing the abnormal muscle in the lower sphincter of the oesophagus), patients are able to gain weight and lead a normal life. Some will develop gastro-oesophageal reflux, especially after surgery which responds to medical treatment. Some recommend endoscopic monitoring for the increased risk of oesophageal carcinoma.

How is Achalasia Diagnosed?

A chest x-ray may show an enlarged oesophagus or a "fluid-level" behind the heart but it is not an accurate test for diagnosing achalasia. - An endoscopy can be done to exclude other causes of dysphagia - such as a benign stricture secondary to reflux disease or a carcinoma (malignancy or cancer).

Prognosis of Achalasia

Surgery often results in longer lasting relief of symptoms, while dilation alone (done at endoscopy) often results in only temporary improvement in symptoms. There is a slightly increased risk of oesophageal cancer.

How is Achalasia Treated?

Dilatation (widening) of the lower oesophagus during an endoscopy is satisfactory in over 80% of patients. This treatment can be complicated in some cases with aspiration pneumonia, reflux, re-stenosis (recurrence of the achalasia) and in rare cases a rupture of the oesophagus. Surgery: Heller's operation - the surgical division of the abnormal muscle layer in the lower oesophagus. Often a Nissen fundoplication (the strengthening of the "valve" between the stomach and the oesophagus by wrapping the upper portion of the stomach, or fundus, around the bottom of the esophagus) is done at the same time due to the high incidence of post-op reflux oesophagitis.

Achalasia References

Braunwald, Fauci, Kasper, Hauser, Longo, Jameson. Harrison's Principles of Internal Medicine. 15th Edition. McGraw-Hill. 2001.
Cotran, Kumar, Collins 6th edition. Robbins Pathologic Basis of Disease. WB Saunders Company. 1999.
Haslet C, Chiliers ER, Boon NA, Colledge NR. Principles and Practice of Medicine. Churchill Livingstone 2002.
Hurst JW (Editor-in-chief). Medicine for the practicing physician. 4th edition Appleton and Lange 1996.
Kumar P, Clark M. Clinical Medicine. WB Saunders 2002;
Longmore M, Wilkinson I, Torok E. Oxford Handbook of Clinical Medicine. Oxford Universtiy Press. 2001
McLatchie G and LEaper DJ (editors). Oxford Handbook of Clinical Surgery 2nd Edition. Oxford University Press 2002.
MEDLINE Plus
Raftery at Churchill's pocketbook of Surgery. Churchill Livingsone 2001.