Rinsho Shinkeigaku (Clinical Neurology)

Case Report

A rare case of inclusion body myositis associated with anti-PM/Scl-75 antibodies

Masayoshi Yamamoto, M.D.1)2), Koji Tsuzaki, M.D.1), Kumi Itani, M.D.3), Naoko Tachibana, M.D., Ph.D.1), Manabu Inoue, M.D., Ph.D.4) and Toshiaki Hamano, M.D., Ph.D.1)

1)Department of Neurology, Kansai Electric Power Hospital
2)Department of Neurology, Kitano Hospital, Tazuke Kofukai Medical Research Institute
3)Depart of Neurology, Kansai Medical University
4)Department of Neurology, Osaka City General Hospital

A 71-year-old man presented with progressive muscle weakness of the four limbs in November 2014. His symptoms had started from the left leg in 2008, resulting in frequent falls. In 2011, he became unable to stand up without a handrail due to weakness of the both legs. Physical examination showed almost symmetric muscle weakness of the arms and legs; MMT4. The CK level was slightly elevated of 304 IU/l. The patient was diagnosed as having inclusion body myositis based on the muscle biopsy findings showing many fibers with rimmed vacuoles in addition to mononuclear cell infiltrating into the endomysium, surrounding and sometimes invading into non-necrotic muscle fibers. Anti-PM/Scl-75 antibodies were positive. Muscle strength improved after intravenous immunoglobulin therapy, although the effect was only temporary. This rare case suggests the autoimmunological etiology in inclusion body myositis.
Full Text of this Article in Japanese PDF (1239K)

(CLINICA NEUROL, 60: 264|267, 2020)
key words: inclusion body myositis, intravenous immunoglobulin therapy, myositis autoantibodies, PM/Scl

(Received: 2-Sep-19)