Reversible oropharyngeal dysphagia secondary to cricopharyngeal sphincter achalasia in a patient with myasthenia gravis: a case report.

Bulbar weakness and fatigue resulting in dysphagia and dysarthria is common in myasthenia gravis. In chronic MG it is often assumed that these symptoms herald an exacerbation of the patient's disease and doses of cholinergic agents and immunomodulatory therapies may be increased, along with initiation of plasma exchange. A case is presented in which dysphagia was refractory to standard MG therapy, leading to the subsequent discovery of cricopharyngeal sphincter achalasia as the primary cause of the patient's symptoms rather than an assumed myasthenia gravis exacerbation. The patient's dysphagia resolved after esophageal dilatation. Cricopharyngeal sphincter achalasia is a common disorder producing dysphagia in the elderly and needs to be considered in the evaluation of a myasthenic patient with worsening dysphagia when standard myasthenia gravis therapy fails. Discussion of myasthenia gravis, cholinergic therapy and cricopharyngeal sphincter achalasia is undertaken. Clinicians are encouraged to consider non-neurologic causes of worsening dysphagia in the myasthenic patient.