Histopathological Investigation of Progressive Encephalomyelitis with Rigidity and Myoclonus: An Autopsy Case Characterized by Oculomotor Dysfunction and Autonomic Failure

• Published in: Internal Medicine p. 3741-24
• Main Authors: Yabata, Hiroyuki, Nakamura, Ryutaro, Sugiyama, Seiji, Tamaki, Yoshitaka, Yamakawa, Isamu, Onoda, Shiori, Ishigaki, Hirohito, Ikeda, Toshimasa, Akagi, Akio, Itoh, Yasushi, Kushima, Ryoji, Yoshida, Mari, Iwasaki, Yasushi, Urushitani, Makoto
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Internal Medicine 2024
• Subjects: anti-glycine receptor antibody; autopsy; pathology; progressive encephalomyelitis with rigidity and myoclonus; progressive encephalomyelitis with rigidity and myoclonus; pathology; autopsy; anti-glycine receptor antibody
• ISSN: 0918-2918; 1349-7235; 1349-7235
• DOI: 10.2169/internalmedicine.3741-24

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a rare disease associated with the presence of anti-glycine receptor (GlyR) antibodies. We herein report an autopsy case of an 80-year-old man diagnosed with anti-GlyR antibody-positive PERM who presented with symptoms of oculomotor dysfunction and autonomic failure. Despite intensive immunotherapy, the neurological symptoms showed almost no improvement, and the patient succumbed to aspiration pneumonia and bacterial translocation. Postmortem pathology revealed mild inflammatory changes and neuronal loss that were disproportionate to a severe clinical presentation. These results suggest that the clinical symptoms of PERM may result from antibody-mediated GlyR internalization, leading to neuronal disinhibition, rather than a neuroinflammatory signature.