1999 Volume 13 Issue 7 Pages 828-831
Late-onset myasthenia gravis is rare and only 5 cases in patents over 80 years of age have been reported in the Japanese literature.
An 82-year-old man with chief complaints of a nasal voice and dysphagia was diagnosed as having myasthenia gravis (Osserman IIB). He had an anterior mediastinal tumor on chest CT and X-ray, with an elevated serum level of antiacetylcholine receptor antibody (2.9ng/ml). An extended thymectomy was performed. The resected specimen was a yellowish, elastic soft mass 5 cm in diameter, including a cystic component 1.5 cm in diameter. After the operation, the patient's symptoms improved markedly and his serum antiacetylcholine receptor antibody decreased to 0.9ng/ml. He was discharged on the 22nd postoperative day without any complications and has been in complete remission for one year since the surgery.
