Achalasia

ACHALASIA OVERVIEW

Achalasia is an uncommon swallowing disorder that affects about 1 in every 100,000 people. The major symptom of achalasia is usually difficulty with swallowing. Most people are diagnosed between the ages of 25 and 60 years. Although the condition cannot be cured, the symptoms can usually be controlled with treatment.

ACHALASIA CAUSE

In achalasia, nerve cells in the oesophagus (the tube that carries food from the mouth to the stomach) degenerate for reasons that are not known. The loss of nerve cells in the oesophagus causes two major problems that interfere with swallowing:

1. The muscles that line the oesophagus do not contract normally, so that swallowed food is not propelled through the oesophagus and into the stomach properly
2. The lower oesophageal sphincter (LOS), a band of muscle that encircles the lower portion of the oesophagus, does not function correctly.

Normally, the LOS relaxes when we swallow to allow swallowed food to enter the stomach. When the food has moved through the oesophagus into the stomach, the LOS muscle contracts to squeeze the end of the oesophagus closed, thus preventing the stomach contents from flowing backwards (refluxing) into the oesophagus.

 In people with achalasia, the LES fails to relax normally with swallowing. Instead, the LES muscle continues to squeeze the end of the oesophagus, creating a barrier that prevents food and liquids from passing into the stomach. Over time, the oesophagus above the persistently contracted LOS dilates, and large volumes of food and saliva can accumulate in the dilated oesophagus. 

ACHALASIA SYMPTOMS

The most common symptom of achalasia is difficulty swallowing. Patients often experience the sensation that swallowed material, both solids and liquids, gets stuck in the chest. This problem often begins slowly and progresses gradually. Many people do not seek help until symptoms are advanced. Some people compensate by eating more slowly and by using manoeuvres, such as lifting the neck or throwing the shoulders back, to improve emptying of the oesophagus.

Other symptoms can include:

• Chest pain
• Vomiting
• Heartburn
• Feeling like you have a lump in your throat
• Losing weight without trying

 ACHALASIA DIAGNOSIS

Achalasia may be suspected based upon symptoms, but tests are needed to confirm the diagnosis.

You will have had 1 or more of the following tests:

• Manometry: Measuring the pressure in your oesophagus and LOS –a thin tube into your mouth or nose and down into your oesophagus. The tube measures the pressure there.
• Barium swallow: You drink "barium, a chalky substance. Then, they take an X-ray as the barium moves down your oesophagus where you can see the outline.
• Gastroscopy: a thin tube with a camera on the end is put into the mouth and down into the oesophagus and stomach to see the lining of the oesophagus and stomach.
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ACHALASIA TREATMENTS

Several options are available for the treatment of achalasia. Unfortunately, none can stop or reverse the underlying loss of nerve cells in the esophagus of patients with achalasia. However, the treatments are usually effective for improving symptoms.

None of the available treatments are expected to restore normal (peristaltic) contractions in the esophagus of patients with achalasia. Rather, the treatments aim to weaken the LOS muscle to the point that it no longer poses a barrier to the passage of food. 

1. Medicines– Different medicines can relax the LOS. People can take these medicines before they eat. Two classes of drugs, nitrates and calcium channel blockers, have LOS muscle-relaxing effects.

 Pros:

• Least invasive option.

Cons:

• Side effects: cause low blood pressure and headache
• Inconvenient: have to be taken 10-30 minutes before all meals
• Ineffective: they become less effective over time

2. Tube feeding, to bypass the oesophagus. A thin tube can be placed through the nose and into the stomach where liquid feed can be given. A tube can be placed through the abdominal wall skin directly into the stomach to place feed. This may be a last resort option if surgery is not wanted or possible and the oesophagus no longer works (end stage achalasia).

Pros:

• Sustains nutrition 

Cons:

• No eating pleasure
• Uncomfortable
• Tubes can dislodge and need to be replaced

3. An injection of botox into the LOS:delivered via a gastroscopy. Botulinum toxin injections temporarily paralyze the nerves that signal the LOS to contract, thereby helping to relieve the obstruction. Botulinum toxin injection also is used occasionally as a diagnostic test for people who appear to have achalasia but who have inconclusive test results.

Pros:

• Minimally invasive
• Symptom improvement in >65% of patients 

Cons:

• Lasts 6-12 weeks then wears off
• Less effective if >50 years old
• Expensive

4. Balloon dilation:during a gastroscopy a balloon is placed across the LOS and inflated to 3cm to widen and tear the muscle open.

Pros:

• Less invasive than surgery (day-stay case)
• Improves symptoms in >75% of patients, 60% are still OK at 1 year.

 Cons:

• Usually recurrent symptoms after 9 months or so, then repeat treatments needed
• Causes scarring which can make other treatments more difficult in the future
• Can cause chest pain (15% of patients), bleeding, reflux and perforation (rare 1%)

5. Keyhole surgery:laparoscopic Heller’s myotomy. Weakens the LOS by cutting its muscle fibres.

Pros:

• Improves symptoms in 70-90%, sustained relief of symptoms in 85% of patients at 10 years.
• A fundoplication (portion of the stomach is wrapped around the oesophagus to prevent the reflux of stomach contents) can be performed simultaneously to reduce risk of reflux 

Cons:

• General anaesthetic required
• Small cuts made in the abdomen
• Type III achalasia not well treated by this method
• Post-operative pain

6. Peroral endoscopy myotomy: (POEM)is an endoscopic technique for performing myotomy of the LOS. In POEM, the endoscopist passes an electrical scalpel through the endoscope to make an incision in the lining of the esophagus and to create a tunnel within the wall of the esophagus (between the inner lining of the esophagus and the outer muscle layer of the esophagus). The endoscope is advanced into that tunnel, and the muscle of the esophagus can be cut using the electrical scalpel device that is passed through the endoscope.

See: POEM patient information 

Pros:

• Minimally invasive (no cuts in the skin)
• Similar efficacy to surgery

Cons:

• General anaesthetic required
• Reflux – requirement of ant-acid PPI post procedure 

Reference: UpToDate: Retrieved Aug 08, 2024.