Achalasia

What is achalasia? How is it defined?

The word achalasia is derived from the Greek word for relaxation khalasis, and translates to ‘failure to loosen or relax’. In medical terms, achalasia is a condition commonly defined by two cardinal characteristics:

• An excessively ‘tight’ lower oesophageal sphincter that fails to relax or open up. The lower oesophageal sphincter is a muscle at the bottom of the oesophagus which ordinarily relaxes and opens up when food or fluid arrives, in order to allow passage into the stomach.

• Absence of normal peristalsis in the body of the oesophagus. Peristalsis is the normal coordinated contraction of the oesophageal muscles which helps propel food down the oesophagus.

 

How common is achalasia?

Achalasia is an uncommon condition. Traditionally the reported incidence of achalasia has been 1 case diagnosed per 100,000 population  each year. However, the reported incidence of achalasia appears to be increasing recently, and may now approach 2.5-3 cases per 100,000 each year. This is not due to the disease truly affecting more people; but rather, improvements in our ability to record, detect and diagnose the condition. 

 

This means that in Australia, there are approximately 650-700 new people diagnosed with achalasia each year, and there are estimated to be at least 6000-7000 persons living with the condition.

 

What is the cause of achalasia?

Patients with achalasia have been found to have damage and/or loss of neurons (nerve cells) in the oesophagus and lower oesophageal sphincter. It is the dysfunction in these neurons that cause the abnormalities in oesophageal function seen in achalasia. The cause for the damage to these neurons is not known, but is suspected to be due to an autoimmune process. However, achalasia has not been found to respond to immune-suppressing medications. This is likely because by the time of diagnosis, the damage to the neurons has already been done, and is not reversible.

 

Is achalasia hereditary?

In general, no. While there are reports of achalasia running in a family, this is exceedingly rare and in general, the family members of a patient with achalasia are not at increased risk of developing the condition. In a very small proportion of achalasia cases, the disease occurs in combination with other rare hereditary disorders (e.g. Allgrove syndrome).

 

What are the symptoms of achalasia?

Symptoms in achalasia tend to come on gradually and slowly progress over months or even years. In patients who develop symptoms that worsen rapidly, consideration should first be given to alternative diagnoses. The symptoms of achalasia predominantly arise from food and fluid not being able to pass through the lower oesophagus into the stomach. Food and fluid gets held up and stuck in the oesophagus, which can give rise to some or all of the following:

• Dysphagia, or difficulty swallowing. The patient may feel that food and/or fluid is getting held up in the chest, and not passing down easily. Sometimes, the sensation of impaired food passage is felt in the throat region, even though the problem is lower down in the oesophagus.

• Regurgitation, i.e. throwing up or spitting up of swallowed food or fluid. Unlike vomiting, regurgitation in achalasia is effortless. That is, the matter is brought up without any heaving or retching. Sometimes, patients describe bringing up a frothy white liquid – this represents swallowed saliva that is unable to pass through into the stomach. 

• Chest pain and/or heartburn – Commonly experienced in achalasia and one of the reasons why the condition is often initially misdiagnosed as GORD (acid reflux). Chest pain may occur due to multiple reasons e.g. ‘spasm’ of oesophageal muscle, or acidic fermentation of food held up in the oesophagus.

• Weight loss, which can be marked in untreated severe achalasia because nutrition is inadequate.

 

Other symptoms which occur less commonly include cough, aspiration, voice hoarseness and sore throat.

 

Is achalasia serious? Can I die from achalasia?

Thankfully, achalasia itself is not a lethal condition. However, it is an important condition to diagnose as it can lead to troubling symptoms, malnutrition and significantly affect a patient’s quality of life. Patients with longstanding achalasia are at a slightly higher risk of developing cancer of the oesophagus compared to the general population, and for this reason screening with endoscopy is often recommended in such patients. However, it is thought that the risk of cancer is predominantly in those with severe, poorly treated disease; and therefore by ensuring the disease is kept under control with effective treatment, the risk of cancer should be negligible.

 

Is achalasia related to GORD (acid reflux)?

GORD is a much more common condition than achalasia. In GORD, stomach acid inappropriately rises into the oesophagus, leading to troubling symptoms. As some of the symptoms of GORD can overlap with achalasia, achalasia is very often initially misdiagnosed as GORD or acid reflux. However in untreated achalasia, acid reflux is actually very uncommon; since the tight, non-relaxing lower oesophageal sphincter that doesn’t allow food to pass down, also acts as a barrier preventing acid from rising up.

 

However, acid reflux can be one of the side effects of therapy for achalasia. Any therapy that ‘opens up’ the lower oesophageal sphincter to let food through, carries some risk of causing acid reflux to occur.

 

How is achalasia diagnosed?

Achalasia can be suspected based on a patient’s symptoms. However, as all of the symptoms can overlap with other disorders, diagnostic tests are always necessary to confirm the diagnosis and assess severity of the condition. Usually, a combination of diagnostic tests are used, as listed below:

• Endoscopy: In advanced, classical cases of achalasia endoscopy may reveal an oesophagus full of food or fluid, which is always abnormal. In milder or early cases of achalasia, the endoscopy may appear completely normal. Sometimes, an endoscopist will report abnormal or decreased peristalsis visible during endoscopy; however this cannot be reliably interpreted as peristalsis cannot be accurately assessed at endoscopy. Similarly, the function of the lower oesophageal sphincter cannot be accurately assessed at endoscopy. One of the major purposes of endoscopy is to exclude an alternative diagnosis, especially cancer of the lower oesophagus. Cancer can occasionally cause a very similar pattern of symptoms and radiological (x-ray) findings as achalasia (termed ‘pseudoachalasia’), but cancer is generally readily identified at endoscopy. 

• Barium swallow: A special type of x-ray test where the patient drinks a contrast liquid (barium) while x-rays are taken of the chest and upper abdomen. The barium provides better definition of the oesophagus, lower oesophageal sphincter and stomach. The barium swallow provides some information about the function of the oesophagus in terms of the quality of peristalsis and how effectively it empties ingested contents into the stomach. In advanced cases of achalasia, a barium swallow will typically reveal a dilated oesophagus which empties very little barium into the stomach. However, in early or mild cases of achalasia, barium swallow is often normal or non-diagnostic. 

• High-resolution oesophageal manometry: Always required for the definitive diagnosis of achalasia. Manometry is a test where the patient is asked to swallow after a thin tube is placed into the oesophagus to take pressure recordings. Manometry can confirm the diagnostic hallmarks of achalasia by identifying absent peristalsis and the failure of the lower oesophageal sphincter to relax and open up during swallowing. Manometry not only confirms the diagnosis of achalasia, but can subtype the condition (Type I vs. Type II vs. Type III achalasia). Establishing the subtype of achalasia provides valuable information regarding prognosis and aids in selecting treatment modality, since some therapies perform differently in Type III vs. Type II achalasia, for example.

 

What is the treatment for achalasia?

The goal of therapy should be for the patient to be able to eat a wide, varied diet with minimal symptoms. Nowadays, several effective treatment options for achalasia exist. While there is no effective treatment for the lack of peristalsis in the oesophagus, treatment is generally directed at the tight lower oesophageal sphincter. However by opening up the sphincter, patients are generally able to eat and drink relatively normally even though there is no peristalsis, as food and fluid can pass through by gravity. For this reason, after any form of successful achalasia treatment, patients need to be conscious of always being upright whilst eating and drinking. Sipping on water during meals is also a helpful strategy to assist food passing down with gravity.

 

Treatment options for achalasia include:

• Surgical (Heller) myotomy: Via keyhole surgery and with the patient under general anaesthesia, several incisions are made on the abdominal wall through which the lower oesophagus and sphincter muscle are visualised. A cut (myotomy) is made through the sphincter muscle, in order to open it up. Myotomy is followed by a partial ‘wrap’ of the top of the stomach around the sphincter muscle in an attempt to reduce acid reflux postoperatively (fundoplication). This usually requires a 1-2 day hospital admission and a longer recovery period.

• Endoscopic pneumatic balloon dilatation: A procedure performed via endoscopy as a day procedure. Under X-ray guidance, a balloon is positioned across the sphincter muscle and inflated for 30-60 seconds. This causes a controlled disruption of the sphincter muscle to open it up. Balloons come in three sizes (30, 35 and 40mm) and for safety reasons it is recommended to start with the smallest balloon. However, the procedure rarely provides patients durable relief unless larger balloon sizes are reached. Therefore, up to three procedures may be required.

• Per-oral endoscopic myotomy (POEM): The newest treatment modality for achalasia. Via endoscopy, a tunnel is made through the inner lining of the oesophagus such that the muscle layer can be visualised. Through this tunnel, a cut (myotomy) can be performed in the sphincter muscle using a special endoscopic knife. The procedure usually requires an overnight hospital stay.

• Botulinum toxin injection: Via endoscopy, botulinum toxin is injected into the lower oesophageal sphincter to loosen and open it up (paralyses the sphincter muscle). Nowadays, botulinum should rarely be performed except in some limited scenarios. While it can be effective, the effect only lasts 3-6 months before symptoms recur.

 

Oral medications for achalasia are no longer recommended as they are poorly effective and often cause troubling side effects. 

 

How do I decide on the right treatment option for achalasia?

Recent high quality studies (e.g. the European Achalasia Study) have shown that all three treatment options (surgery, pneumatic balloon dilatation and POEM) are equally effective for the treatment of achalasia. All are acceptable first-line treatment options for patients with achalasia. However, each treatment has its own pros and cons, some of which are listed in the table below. Ultimately, the choice of treatment needs to be individualised to each patient and partly depends on the patient’s own preference.