title: [A case of anti-PL7 antibody positive myositis and a clinical and pathological review of the anti-synthetase syndrome].
abstract: A 52-year-old woman was admitted to our hospital with muscle pain and an elevated creatine kinase level. She had experienced wrist pain at onset seven years ago. The initial possible diagnoses were rheumatoid arthritis and adult-onset Still disease. The patient received corticosteroid and immunosuppressant therapy but experienced deterioration of symptoms. The symptoms of muscle pain and mild creatine kinase elevation emerged four years prior to her visit. Further elevation of creatine kinase was observed for three months before her visit despite adjusting the immunosuppressant dose. On admission, she presented with muscle moderate weakness of the trunk and extremities and pain of the shoulder and medial thigh muscles. Elevation of muscle enzymes and inflammatory response were also detected, and the anti-PL7 antibody was positive. Muscle biopsy from biceps brachii revealed necrotizing myopathy with necrotic and regenerated muscle fibers. The final diagnosis was anti-PL7 antibody positive myositis. The patient was treated with a higher dose of prednisolone and an adequate dose of tacrolimus. Following this treatment, the symptoms were improved. Anti-ARS (aminoacyl t-RNA synthetase) antibodies such as anti-PL7 antibody are useful in diagnosis and for prognostic prediction. Further investigation of patients with anti-ARS antibodies positive myositis is required.
authors.affiliation: Department of Neurology, Hokkaido University Graduate School of Medicine.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Matsushima
authors.forename: Yuka
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Ikuko
authors.initials: I
authors.lastname: Takahashi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Sato
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirotani
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kano
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yabe
authors.forename: Hidenao
authors.initials: H
authors.lastname: Sasaki
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009220:Myositis / Q000188:drug therapy / Q000276:immunology*; D013577:Syndrome; D016559:Tacrolimus / Q000627:therapeutic use
chemical_list: D001323:Autoantibodies; D000604:Amino Acyl-tRNA Synthetases; D016559:Tacrolimus