Achalasia and Cricopharyngeal Sphincter Dysfunction in a Patient With Myasthenia Gravis: A Case Report

This case report describes an 82-year-old female patient with myasthenia gravis (MG) who presented with worsening dysphagia. The patient was found to have cricopharyngeal sphincter and esophageal achalasia, and a percutaneous endoscopic gastrostomy (PEG) tube was placed due to severe pharyngeal dysphagia and cricopharyngeal dysfunction. The patient had class IVb myasthenia gravis and was treated with intravenous immunoglobulin (IVIG), prednisone, and pyridostigmine. The report discusses the link between myasthenia gravis and dysphagia, which is seen in 20% of patients. The report also explores the relationship between myasthenia gravis and achalasia, which is a rare disorder characterized by the failure of relaxation of the sphincter muscles. While myasthenia gravis leads to muscle weakness and should not cause achalasia, there have been a few case reports describing a link between the two disorders. Cricopharyngeal dysfunction, which is a common disorder causing dysphagia in the elderly, was also noted in the patient. The report highlights that cricopharyngeal dysfunction may be primary or secondary, with the latter often being associated with inflammatory myopathies such as polymyositis or mixed connective tissue disorders. The patient did not have a workup for other autoimmune diseases that could have been the cause of achalasia.