RÉSUMÉ
Valosin-containing protein (VCP)-related multisystem proteinopathy (MSP1) is a rare genetic disorder marked by abnormal protein accumulation. This study presents the case of a 52-year-old woman with MSP1, showing progressive weakness, gait disturbances, and respiratory muscle weakness over five years. The clinical examination revealed diverse presentations, including neurogenic changes in electrophysiologic study, multifocal fatty changes of muscle, and cognitive impairment with a confirmed VCP gene mutation through genetic testing. Notably, we identified lobulated myofibers in the muscle biopsy, an unusual finding in MSP1. This is the first report of lobulated myofibers in MSP1 with multisystem involvement. Identifying unique muscle biopsy results in suspected MSP1 patients through careful neurological examinations and timely genetic testing may help in early diagnosis and appropriate management.