Esophageal smooth muscle dysfunction in oculopharyngeal muscular dystrophy

Oculopharyngeal muscular dystrophy (OPMD) is a rare genetic disorder with late-onset progressive myopathy affecting mainly head and neck striated muscles. It is more common in certain ethnic communities. Dysphagia was usually attributed to the malfunction of striated pharyngeal muscles. We studied a group of Bukharan immigrants affected by this disorder (N = 13). Esophageal studies, including endoscopy, manometry, and scintigraphic emptying were performed. Very low pharyngeal pressures were measured. Upper esophageal pressures (UEP) were in the normal range in eight patients, and above normal in three patients. Four also had low lower esophageal sphincter pressure. Esophageal body peristaltic activity was grossly impaired in all patients: mainly nonpropulsive, simultaneous, retrograde, and failed activity was recorded. Marked retention of isotopic material was demonstrated in all patients studied, usually in the middle and lower parts of the body, ranging from 17 to 100% retention. The dysphagia in OPMD is due not only to dysfunction of pharyngeal and upper esophageal striated muscle, but also has a significant smooth muscle component.