Usefulness of the video fluoroscopic examination of swallowing in a patient with anti–muscle–specific receptor tyrosine kinase antibody–positive myasthenia gravis

Abstract

Anti–muscle–specific receptor tyrosine kinase antibody–positive myasthenia gravis (Musk–MG) is characterized by bulbar involvement associated with risks for aspiration and suffocation. However, objective evaluations including the video fluoroscopic examination of swallowing (VF) has been reported in only one case. We report the second such case. A 46–year–old man with Musk–MG regularly visited our outpatient clinic, but had difficulty of swallowing and marked nasal voice without cough. He was then admitted to our hospital. VF revealed silent aspiration. Oral feeding was halted, and he received one round of intravenous immunoglobulin therapy. Because swallowing functions on VF did not improve sufficiently, two rounds of methylprednisolone pulse therapies were added, and improved swallowing functions with disappearance of swallowing symptoms. The results of VF were useful to determine the halting and commencement of oral feeding, food textures, and therapeutic strategies. His condition improved without aspiration pneumonia or suffocation. Our findings highlight the importance of VF for evaluation of therapeutic effects in diseases associated with severe dysphagia, including MG.