Achalasia is an esophageal motility disorder in which the lower esophageal sphincter (LES) fails to relax during swallowing. The disorder occurs when ganglionic cells in Auerbach’s (myenteric) plexus are destroyed due to autoimmunity or infection (Chagas’ disease).
The patient’s symptoms (dysphagia, halitosis, and nocturnal food regurgitation) are typical of achalasia and other esophageal motility disorders. Manometry is used to diagnose achalasia, and patients with the disease show diffuse esophageal spasm, lack of functional peristalsis, and failure of the lower esophageal sphincter to relax upon swallowing. Medical treatment includes medications that reduce LES tone, including nifedipine, nitrates, and botulinum toxin. Myotomy and endoscopic balloon dilation of the LES are surgical treatment options.
Abell and Werkman review gastrointestinal motility disorders. Clinical history can localize gastrointestinal motility disorders. Dysphagia, odynophagia, heartburn and reflux point to esophageal origins, while nausea, vomiting, anorexia, bloating and abdominal pain point to stomach and intestine disorders. Right upper quadrant pain implicates liver pathology.
Francis and Katzka review the pathophysiology of achalasia and current treatment options. Histologic analysis of myotomy and esophagectomy specimens from patients with achalasia shows that the degeneration of ganglion cells in the myenteric plexus of the esophageal body and the LES cause disease.
Illustration A shows broad dilation of the proximal esophagus with narrowing of the distal esophagus around the LES (‘bird’s beak appearance’) in achalasia.
Answers 1,2,4,5: The lamina propria, submucosa, Meissner’s plexus, and the muscularis mucosa are not associated with the pathophysiology of achalasia.
Francis DL, Katzka DA. Achalasia: update on the disease and its treatment. Gastroenterology. 2010 Aug;139(2):369-74. Epub 2010 Jun 18. Review
PMID:20600038 (Link to Abstract)
Abell TL, Werkman RF. Gastrointestinal motility disorders. Am Fam Physician. 1996 Feb 15;53(3):895-902. Review.
PMID:8594865 (Link to Abstract)
USMLE World Step 1 QBank Question #828. Copyright © USMLEWorld, LLC 2012