The Pulse | Thursday, March 11, 2021
Achalasia: Everything You Thought You Knew and Then Some
Achalasia is a rare disease of unknown etiology, affecting 1-2 out of every 100,000 individuals. It is a classic esophageal motility disorder characterized by loss of peristalsis in the distal esophagus and failure of the lower esophageal sphincter (LES) to relax with swallowing. Below are some clinical pearls to help you become more familiar with this uncommon disease.
History: Achalasia was first described in 1672 by Sir Thomas Willis (of Circle of Willis fame), a professor of natural philosophy at Oxford. He described a “food blockage inside the esophagus,” and interestingly, used a sponge attached to a carved whalebone to dilate a patient’s esophagus (which is no longer the standard of care). The term “achalasia” — a Greek term for “lack of relaxation” — was not coined until 1927, when Sir Arthur Hurst published “The Treatment of Achalasia of the Cardia.”
Etiology: The true cause is unknown, but it is thought to originate from a chronic viral infection (herpes zoster or measles) in the presence of an underlying genetic susceptibility. This leads to inflammation of the neurons within the muscular wall of the esophagus (myenteric plexus). Antibodies eventually form against these neurons, which ultimately lead to their destruction.
Clinical Features: The development of achalasia is very gradual, and most patients experience symptoms for four or five years before seeking medical attention. Patients are often treated for other disorders (i.e., GERD) before a diagnosis is made. In addition, patients with achalasia also have an increased risk for developing esophageal cancer. The most common symptoms reported by patients include:
- Dysphagia to solids (91%)
- Dysphagia to liquids (85%)
- Regurgitation of undigested food (76-91%)
- Chest pain (40-60%)
Diagnostic Studies: The essential diagnostic test is high-resolution manometry. Characteristic findings on manometry include aperistalsis in the distal 2/3 of the esophagus, as well as incomplete relaxation and a high resting pressure of the lower esophageal sphincter. An EGD is performed to rule out pseudoachalasia (due to an underlying malignancy). A barium esophagram may show a dilated and tortuous esophagus that terminates in what the radiologist calls a “bird’s beak.” FLIP technology is evolving as an endoscopic screening tool for achalasia.
Treatment Options: There is no cure for achalasia, so the goal of therapy is palliation of symptoms. A few options with varying degrees of efficacy include:
- Medical therapy with nitrates and calcium-channel blockers is reserved for patients that are too frail or ill to undergo surgical therapy, and is otherwise not very effective.
- Botox injections into the LES shows good initial relief, but 50% of patients will need retreatment in six months.
- Graded pneumatic dilatation is initially effective with 85% claiming symptom relief at one month and results lasting several years. However, over one-third of patients will still require retreatment.
- Both Botox and pneumatic dilatation make subsequent surgical myotomy more difficult, but not prohibitive.
Surgical Options: Most clinicians agree that achalasia is best treated with some form of esophageal myotomy. A surgical myotomy was first performed in 1913 by Dr. Ernest Heller, and the laparoscopic approach with partial fundoplication is currently considered first line therapy for a confirmed diagnosis (90% successful in relieving symptoms). Per Oral Endoscopic Myotomy, or POEM, is a newer endoscopic approach to the myotomy. Some studies suggest that POEM is better at relieving dysphagia, but with a higher incidence of symptomatic and pH-positive GERD (since no fundoplication is performed).
I hope this brief review gives you a better understanding of why achalasia is a disease that is often “hard to swallow.”