Mastering Medical
USMLE Step 1 · Gastrointestinal

Achalasia vs Diffuse esophageal spasm

How to tell Achalasia and Diffuse esophageal spasm apart when a board question makes them look alike.

Fastest separator

Achalasia is tight nonrelaxing LES with bird-beak narrowing; diffuse spasm is uncoordinated contraction with corkscrew appearance.

Side by side

AchalasiaDiffuse esophageal spasm
Key clue

Dysphagia to solids and liquids with regurgitation, bird-beak narrowing, and impaired lower esophageal sphincter relaxation.

Intermittent chest pain and dysphagia with uncoordinated esophageal contractions and corkscrew appearance.

Mechanism

Loss of inhibitory myenteric neurons prevents coordinated LES relaxation.

Disordered esophageal smooth muscle contraction creates simultaneous, nonpropulsive contractions while LES relaxation is not the central defect.

Labs and tests

Manometry with high LES pressure and impaired relaxation supports achalasia.

Corkscrew esophagus or simultaneous high-amplitude contractions supports diffuse esophageal spasm.

The trap

Both can cause dysphagia and chest discomfort, so manometry pattern and barium morphology separate them.

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The repair move

For esophageal motility, decide whether the main problem is LES nonrelaxation or uncoordinated contractions.

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Core

A patient has progressive dysphagia to solids and liquids, regurgitation, bird-beak narrowing on barium swallow, and failure of the lower esophageal sphincter to relax. Which diagnosis is most likely?

Show answer and explanation

Answer: A. Achalasia. Achalasia causes impaired LES relaxation with dysphagia to solids and liquids and bird-beak narrowing.

Why the other choices are tempting

  • B. Diffuse esophageal spasm causes intermittent chest pain/dysphagia with corkscrew esophagus.
  • C. Scleroderma esophagus has low LES tone and dysmotility with reflux.
  • D. GERD causes reflux symptoms rather than bird-beak obstruction.
  • E. Adenocarcinoma causes progressive obstructive symptoms with mass or stricture.

Flashcards

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What manometry pattern favors achalasia?

High LES pressure with impaired relaxation supports achalasia.

What barium swallow pattern favors diffuse esophageal spasm?

A corkscrew esophagus reflects uncoordinated contractions.

Quick answers

What is the fastest way to tell Achalasia from Diffuse esophageal spasm?

Achalasia is tight nonrelaxing LES with bird-beak narrowing; diffuse spasm is uncoordinated contraction with corkscrew appearance.

What is the key clue for Achalasia?

Dysphagia to solids and liquids with regurgitation, bird-beak narrowing, and impaired lower esophageal sphincter relaxation.

What is the key clue for Diffuse esophageal spasm?

Intermittent chest pain and dysphagia with uncoordinated esophageal contractions and corkscrew appearance.

What is the common trap with Achalasia vs Diffuse esophageal spasm?

Both can cause dysphagia and chest discomfort, so manometry pattern and barium morphology separate them.