Article: Achalasia

Achalasia or acalasia is a failure of a ring of muscle (as a sphincter) to relax (completely). It refers most commonly to esophageal achalasia, which is a neuromuscular disorder of the esophagus characterized by (1) the reduced ability to move food down the esophagus (peristalsis), and (2) the inability of the cardia (also called lower esophageal sphincter or "LES")- to relax properly in response to swallowing.

Synonyms are achalasia cardiae, cardiospasm, dyssynergia esophagus, esophageal aperistalsis.

Signs and symptoms

• Dysphagia, or difficulty swallowing
• Regurgitation of undigested food
• Heartburn
• Chest pains, which sometimes increase after eating and may radiate to the back, jaw, neck, and arms
• Weight loss
• Coughing, especially at night or when lying down

Diagnosis

Due to the similarity of symptoms, achalasia can be misdiagnosed as other disorders, such as gastroesophageal reflux disease (GERD) and Chagas disease. Unfortunately for patients with this condition, it is not uncommon for achalasia to be misdiagnosed -- or not diagnosed at all -- for many years.

• X-ray with a barium swallow or esophagography. Shows narrowing at the level of the gastroesophageal junction ("bird beak" presentation of the lower esophagus), and various degrees of megaesophagus (esophageal dilation).
• Endoscopy, which provides a view from within the esophagus.
• Manometry, the key test for establishing the diagnosis. Measures the pressure induced in different parts of the esophagus and stomach during the act of swallowing.
• CT scan, which provides further visual evidence.

Complications

1. Gastroesophageal reflux disease-GERD or heartburn.
2. Barrett's esophagus or Barrett's mucosa: in 10% of patients.
3. There are two kinds of esophageal cancer: squamous cell carcinoma and adenocarcinoma. There are predisposing conditions that, if present for a long time, may lead to esophageal adenocarcinoma, like achalasia (in up to 5% of cases, Barrett's esophagus leads to esophageal adenocarcinoma).

Treatment and new expectations

• Balloon (pneumatic) dilation. The muscle fibers are stretched. Gastroesophageal reflux (GERD) occurs after dilatation in 25% to 35% of patients. Is a risk to later Heller myotomy.
• Medication:
  • Intra-sphincteric injection of botulinum toxin (or botox), to paralyze cardia and prevent spasms. Like the botox injected for cosmetic reasons, this result is only temporary, and symptoms will return in the majority of patients within a year.
  • Drugs that reduce LES pressure such as nifedipine and nitroglycerin may be useful.
• Heller myotomy, which can usually be performed via laparoscopic surgery.
• Transplant and artificial cardia. (In theory -- this does not appear to be common in practice.)

See also

• endoscopy
• esophageal motility disorder.