title: HLA typing in focal myositis.
abstract: It is still controversial if idiopathic focal myositis is a part of systemic polymyositis. We present here four patients, including identical twins, with focal myositis accompanied by the same HLA typings. Gradually developing unilateral calf muscle pain was an initial symptom in all patients. Neither muscular weakness nor creatine kinase (CK) elevation was observed, while minimal inflammatory findings such as erythrocyte sedimentation rate (ESR) increase appeared in serum. Magnetic resonance imaging (MRI) revealed localized abnormalities of calf muscles. Biopsy specimen was characterized by perimysial and endomysial inflammatory infiltration consisted of T cells and macrophages and rare necrotic fibers. Corticosteroid administrations ameliorated their symptoms and signs, though recurrence occurred along with decreasing doses. HLA typings common to all patients were A2, B62, Cw3, and DQ3, whereas HLA-D DNA typings were DQB1 *0303 for two patients, and DQB1*0302 for three patients. These findings suggest that at least some focal myositis may be a new disease unit, with a common genetic background but not a part of systemic polymyositis.
authors.affiliation: Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. sekiguch@med.kobe-u.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Sekiguchi
authors.forename: Fumio
authors.initials: F
authors.lastname: Kanda
authors.forename: Kenichi
authors.initials: K
authors.lastname: Oishi
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Hamaguchi
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Nakazawa
authors.forename: Nobuya
authors.initials: N
authors.lastname: Maeda
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishihara
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chihara
mesh_terms: D000328:Adult; D001799:Blood Sedimentation; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006649:Histocompatibility Antigens / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D006650:Histocompatibility Testing / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000378:metabolism / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009220:Myositis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D013194:Staining and Labeling / Q000379:methods
chemical_list: D006649:Histocompatibility Antigens