title: Myositis with antimitochondrial antibodies diagnosed by rectus abdominis muscle biopsy.
abstract: BACKGROUND
  Antimitochondrial antibodies are autoantibodies detected in 90% of primary biliary cirrhosis (PBC) patients. Some PBC cases are complicated by myositis, which is difficult to confirm due to minimal histological evidence of inflammation in limb muscles.
  
  
  METHODS
  Our aim was to determine the extent of inflammatory changes in a truncal muscle biopsy specimen from a PBC patient.
  
  
  RESULTS
  A 48-year-old woman with a 5-year history of atrial fibrillation and chronic heart failure was evaluated for elevated serum creatine kinase level. Antimitochondrial M2 antibodies were detected, and PBC was diagnosed. A biceps brachii biopsy specimen showed mild, non-specific myogenic changes; a second biopsy was performed on the rectus abdominis muscle, which showed typical inflammatory changes. Myositis with antimitochondrial M2 antibodies was confirmed.
  
  
  CONCLUSIONS
  In myositis patients with antimitochondrial M2 antibodies, muscles of the extremities are involved to a lesser extent. Radiological and histological examination focusing on truncal muscles, including a biopsy, is important.
authors.affiliation: Division of Neurology, Kobe University Graduate School of Medicine and Kobe University Hospital, 7-5-2 Kusunoki-cho, Chuo-Ku, Kobe, Hyogo 650-0017, Japan. onlytan@med.kobe-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Uenaka
authors.forename: Hisatomo
authors.initials: H
authors.lastname: Kowa
authors.forename: Kenji
authors.initials: K
authors.lastname: Sekiguchi
authors.forename: Kakuya
authors.initials: K
authors.lastname: Nagata
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ohtsuka
authors.forename: Fumio
authors.initials: F
authors.lastname: Kanda
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Toda
mesh_terms: D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D005260:Female; D006801:Humans; D008105:Liver Cirrhosis, Biliary / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D008875:Middle Aged; D008928:Mitochondria / Q000276:immunology* / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology*; D009220:Myositis / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology
chemical_list: D001323:Autoantibodies