Functional obstruction at the gastroesophageal junction.
M/C cause of dysphagia
Auto-immune conditions: Sjogren’s syndrome, Systemic Lupus Erythematosus and uveitis
Infectious agents: Chagas disease, varicella zoster virus and Guillain-Barre syndrome
Triple “A” syndrome: Triad of achalasia, alacrima and adrenocorticotrophic hormone resistant adrenal insufficiency
Inflammatory changes within the oesophagus following the causative insult result in the loss of postganglionic inhibitory neurons in the myenteric plexus and a consequent reduction in the inhibitory transmitters, nitric oxide and vasoactive intestinal peptide. The excitatory neurons remain unaffected, with the resulting imbalance between excitatory and inhibitory neurons preventing lower oesophageal sphincter relaxation.
Due to initial non-specific symptoms in early stage disease and the low prevalence of achalasia worldwide, the condition often goes undiagnosed for many years, giving rise to features of late stage disease and their associated complications.
Similar to that of gastro-oesophageal reflux:
Retrosternal chest pain typically after eating
Progressive dysphagia (Cardinal sign):
Lack of peristalsis and a non-relaxing lower oesophageal sphincter
Late (established) disease:
Regurgitation, particularly at night, with aspiration of undigested food
Result of the natural course of the condition:
Squamous cell carcinoma (SCC): M/C oesophageal cancer in patients with achalasia
High resolution manometry with pressure topography plotting:
gold standard in diagnosis of achalasia, classically showing aperistalsis and failure of relaxation of the lower oesophageal sphincter
Uncoordinated/absent peristalsis + ↑ LES resting pressure
Type I (classic): Minimal contractility in the esophageal body
Type II: Achalasia with intermittent panesophageal pressurization
Type III (spastic): Premature/spastic distal esophageal contractions
Not accurate in diagnosis but necessary to exclude a carcinoma at the lower end of the oesophagus
Bird’s beak appearance (pathognomonic) of the distal oesophagus with dilatation of the oesophagus proximally
Upper GI endoscopy:
Other imaging modalities:
There is no cure for achalasia. Thus, treatment is aimed at relieving symptoms by improving LES physiology, which leads to reduced functional obstructions and facilitates esophageal emptying. This may be achieved through pharmacologic, endoscopic, or surgical methods.
Endoscopic management (1st line):
POEM (Per Oral Endoscopic Myotomy)
Gradual pneumodilation (balloon dilatation): Balloon positioned across LES and inflated, effectively rupturing the muscle of the affected segment.
Heller’s surgical myotomy:
Creating a longitudinal division of the circular muscle of the lower oesophageal sphincter, extending this both proximally and distally onto the cardia. Laparoscopic technique commonly performed
Partial posterior fundoplication following cardiomyotomy
Anti-reflux procedure: For treating GERD following surgery