title: Inclusion body myositis coexisting with hypertrophic cardiomyopathy: an autopsy study.
abstract: Inclusion body myositis is an inflammatory myopathy characterized pathologically by rimmed vacuoles and the accumulation of amyloid-related proteins. Autopsy studies in these patients, including histochemical examinations of multiple skeletal muscles, have not yet been published. In this paper, we describe the autopsy findings of a patient with inclusion body myositis and hypertrophic cardiomyopathy. A 69-year-old man, who was a human T lymphotropic virus type 1 carrier, exhibited slowly progressive muscle weakness and atrophy, predominantly affecting the scapular, quadriceps femoris, and forearm flexor muscles. His disease course was more rapidly progressive than that typically observed; the patient died suddenly of arrhythmia 5 years after diagnosis. Autopsy findings revealed that multiple muscles, including the respiratory muscles, were involved. Longitudinal studies revealed an increased frequency of rimmed vacuoles and p62/sequestosome 1- and/or TAR DNA-binding protein 43-positive deposits in autopsied muscles, although the amount of inflammatory infiltrate appeared to be decreased. We speculated that muscle degeneration may be more closely involved in disease progression compared with autoimmunity. Genetic analysis revealed a myosin binding protein C3 mutation, which is reportedly responsible for familial hypertrophic cardiomyopathy. This mutation and human T lymphotropic virus type 1 infection may have affected the skeletal muscles of this patient.
authors.affiliation: Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
authors.forename: Yukie
authors.initials: Y
authors.lastname: Inamori
authors.forename: Itsuro
authors.initials: I
authors.lastname: Higuchi
authors.forename: Teruhiko
authors.initials: T
authors.lastname: Inoue
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sakiyama
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hashiguchi
authors.forename: Keiko
authors.initials: K
authors.lastname: Higashi
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Shiraishi
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Okubo
authors.forename: Kimiyoshi
authors.initials: K
authors.lastname: Arimura
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Mitsuyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takashima
mesh_terms: D000368:Aged; D001344:Autopsy; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis* / Q000453:epidemiology* / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D015897:Comorbidity; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology; D009154:Mutation / Q000235:genetics; D009206:Myocardium / Q000473:pathology; D018979:Myositis, Inclusion Body / Q000175:diagnosis* / Q000453:epidemiology* / Q000235:genetics; D000099163:Myosin Binding Protein C
chemical_list: D002352:Carrier Proteins; D000099163:Myosin Binding Protein C