How is distal esophageal motor disorder different from a mechanical obstruction in presentation?

• A. Motor disorders may cause both solids and liquids dysphagia and regurgitation; mechanical obstructions usually present with progressive solid-food dysphagia first
• B. Mechanical obstruction tends to affect liquids first
• C. Motor disorders only affect solids
• D. Mechanical obstruction never causes regurgitation

Answer: (A)

Distal esophageal motor disorders disrupt the coordinated propulsion and relaxation of the esophagus, so the problem is with moving the bolus rather than a fixed blockage. Because of this propulsion failure, both solids and liquids can be difficult to swallow from the outset, and food may regurgitate because it’s left in the distal esophagus to stagnate. A mechanical obstruction, on the other hand, is a physical narrowing or barrier; it tends to trap larger, solid boluses first, so patients typically develop progressive dysphagia to solids before liquids as the obstruction tightens. Regurgitation can occur with stagnation proximal to a blockage, but the classic early pattern for a mechanical obstruction is solids-first dysphagia, whereas motor disorders produce initial trouble with both solids and liquids along with regurgitation from stasis.