Achalasia
Achalasia is a primary esophageal motility disorder from myenteric plexus degeneration that causes failure of lower esophageal sphincter relaxation and aperistalsis, producing dysphagia to solids and liquids with regurgitation. Diagnosis requires endoscopy to exclude pseudoachalasia followed by esophageal manometry, and definitive treatment is pneumatic dilation, laparoscopic Heller myotomy, or POEM.
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What this article covers
- Overview
Definition: achalasia ("failure to relax") is a primary esophageal motility disorder defined by inadequate LES relaxation together with aperistalsis of the esophageal body.
- Epidemiology
Rare disease: annual incidence of approximately 1 per 100,000 individuals.
- Risk factors
Idiopathic in most patients: no identifiable trigger in the majority of cases; considered the primary form.
- Pathophysiology
Loss of inhibitory neurons first: selective degeneration of nitric-oxide-releasing inhibitory ganglion cells in the myenteric (Auerbach) plexus of the esophageal body and LES.
- Clinical features
Dysphagia to solids and liquids simultaneously: the defining symptom, present from symptom onset rather than progressing from solids alone, distinguishing achalasia from mechanical obstruction (peptic stricture, ring, or cancer).
- Differential diagnosis
Pseudoachalasia (malignant GEJ infiltration): identical manometric and radiographic findings, but shorter symptom duration (under one year), more profound weight loss, and older age; distinguished by…
- Diagnosis
The diagnosis is confirmed by high-resolution esophageal manometry, the definitive test: it shows incomplete or absent LES relaxation with an elevated integrated relaxation pressure plus 100%…
- Management
Confirm fitness for a definitive procedure first: healthy patients able to tolerate a procedure should proceed to pneumatic dilation, laparoscopic Heller myotomy, or POEM rather than medical therapy…
- Complications
Aspiration pneumonia: recumbent regurgitation of retained esophageal contents is aspirated, particularly with long-standing untreated disease.
- Prognosis
Definitive therapy is generally durable: most patients treated with laparoscopic Heller myotomy, POEM, or pneumatic dilation achieve substantial, long-lasting symptom relief.
- Prevention
No primary prevention exists for idiopathic achalasia: the disease is not preventable because its trigger is unknown in most patients.
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