Rinsho Shinkeigaku (Clinical Neurology)

Case Report

A case of anti-MuSK positive MG with recurrent right-sided heart failure as the initial manifestation

Yasuko Matsumoto, M.D., Ph.D.1), Keisuke Shima, M.D., Ph.D.1)2), Kazuyoshi Yamaguchi, M.D.1) and Ai Shimizu, M.D.3)

1) Department of Neurology, Ishikawa Prefectural Central Hospital
2) Department of Neurology, Toyama Prefectural Central Hospital
3) Department of Neurology, Kanazawa Medical Center

We report a case of anti-MuSK antibody (Ab)-positive myasthenia gravis (MG) in a patient who developed recurrent right-sided congestive heart failure. The patient presented with right-sided congestive heart failure of unknown etiology, necessitating hospitalization on three occasions over a 6-month period. During the third episode of hospitalization, she developed disturbance of consciousness, and heart failure was attributed to carbon dioxide narcosis. We performed various investigations including an anti-MuSK Ab assay, which showed positive results, and she was diagnosed with MG based solely on anti-MuSK Ab positivity. Selective plasma exchange did not produce a satisfactory therapeutic effect, and she received additional intravenous immunoglobulin, plasmapheresis, and oral immunosuppressive therapy after which she was successfully weaned off the ventilator. This case report highlights the following points: (a) Recurrent right-sided congestive heart failure may be the first manifestation of anti-MuSK Ab-positive MG and, (b) detection of the anti-MuSK Ab alone is a convincing rationale to diagnose patients with MG.
Full Text of this Article in Japanese PDF (1123K)

(CLINICA NEUROL, 60: 791−794, 2020)
key words: MuSK antibody, myasthenia gravis, right heart failure, first manifestation

(Received: 8-May-20)