A case of Mu SK myasthenia gravis associated with solitary lymphadenopathy and insidious autoimmune‐like diffuse encephalopathy

We report an 81‐year‐old woman with anti‐muscle‐specific kinase (Mu SK ) antibody‐positive myasthenia gravis ( MG ) associated with solitary lymphadenopathy and insidious encephalopathy. At the age of 74, her myasthenic symptoms were remitted by immunosuppressive therapy and solitary abdominal lymphadenopathy was removed from the mesentery. Histopathological examinations showed follicular hyperplasia with marked IgG4‐positive plasma cell...