A 65-year-old man comes to the office due to a several month history of difficulty swallowing and frequent coughing during meals. His wife reports that his breath odor has changed and his voice sounds "gurgly." The patient occasionally regurgitates food or medications taken earlier in the day. Medical history is significant for hypertension, gastroesophageal reflux disease, and osteoarthritis of the right knee. Medications include hydrochlorothiazide, famotidine, and, occasionally, naproxen as needed. Which of the following mechanisms leads to the development of this patient's condition?
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This patient with dysphagia, halitosis, and a history of regurgitating undigested food likely has a Zenker (pharyngoesophageal) diverticulum. Patients are typically age >60 and have an insidious onset of progressive dysphagia. Retained food trapped in the pouch causes halitosis and sometimes a "gurgling" sound. This food is often regurgitated later and appears undigested because it has not been exposed to gastric enzymes. Aspiration of the regurgitated food may lead to recurrent aspiration pneumonia.
Abnormal spasm or diminished relaxation of the cricopharyngeal muscles during swallowing (cricopharyngeal motor dysfunction) is the underlying mechanism of the formation of a Zenker diverticulum. Increased intraluminal pressure above the cricopharyngeus muscle eventually causes herniation of the mucosa, resulting in a pulsion (ie, pushing) pseudodiverticulum. This occurs through a zone of muscle weakness between inferior pharyngeal constrictor fibers and the cricopharyngeus muscle.
Diagnosis is confirmed with a contrast swallow study. Treatment is surgical. The cricopharyngeus muscle is divided (cricopharyngeal myotomy), and the diverticulum may be removed (ie, diverticulectomy) or combined with the esophageal lumen (ie, diverticulotomy).
(Choice A) Abnormal cellular proliferation is the underlying pathophysiologic defect in neoplasia. Esophageal cancer may cause dysphagia, but not typically regurgitation of undigested food.
(Choice B) Gastroesophageal reflux disease (GERD) is frequently associated with Zenker diverticula, but it is not causative. GERD can cause dysphagia and regurgitation of acid, but it does not typically cause regurgitation of undigested food or medications that were consumed several hours before.
(Choice C) Chronic inflammation in the mediastinum (eg, due to tuberculosis or fungal infections) can lead to the formation of midesophageal diverticula due to the pull (traction) of adjacent scar tissue. In contrast to pulsion diverticula, these traction diverticula are true diverticula (ie, involve the mucosal, submucosal, and muscular layers). Traction diverticula are very rare, and this patient has no signs of tuberculosis or other mediastinal inflammatory processes.
(Choice D) Metabolic abnormalities (eg, iron deficiency) may be associated with upper esophageal webs (Plummer-Vinson syndrome) that can cause an insidious onset of dysphagia. However, halitosis and regurgitation of undigested food are not typical.
Educational objective:
Diminished relaxation of the cricopharyngeus muscle during swallowing results in increased intraluminal pressure in the hypopharynx. This may cause the mucosa to herniate, forming a Zenker (pharyngoesophageal) diverticulum, which presents in patients age >60 with dysphagia, halitosis, and regurgitation of undigested food.