title: The lymphoid follicle variant of dermatomyositis.
abstract: OBJECTIVE
  To investigate the clinical and morphologic spectrum of early adult-onset dermatomyositis (DM), an inflammatory disease that affects small vessels of the muscle and the skin.
  
  
  METHODS
  Histologic evaluation of frozen muscle samples was employed to visualize the cellular organization of ectopic lymphoid structures in muscle biopsies obtained from 2 patients diagnosed with DM. Clinical presentation and morphologic features, as well as treatment and follow-up, were assessed and documented. Electron microscopy was used to confirm the light microscopic diagnosis of DM. Clonality analysis of B-cell populations using PCR was performed.
  
  
  RESULTS
  Muscle biopsy of both patients fulfilled the morphologic European Neuromuscular Centre criteria of DM. Analyses of muscle biopsy samples revealed ectopic lymphoid follicle-like structures that showed a remarkable similarity to secondary lymphoid organs (SLOs) with distinct T- and B-cell compartmentalization. Our 2 patients exhibited an atypical and mild clinical presentation and responded favorably to therapy.
  
  
  CONCLUSIONS
  The clinical and histopathologic features of DM can be atypical, and the presence of SLOs is not inevitably linked to an unfavorable prognosis.
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Josefine
authors.initials: J
authors.lastname: Radke
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Debora
authors.initials: D
authors.lastname: Pehl
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Aronica
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Dieneke
authors.initials: D
authors.lastname: Schonenberg-Meinema
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Udo
authors.initials: U
authors.lastname: Schneider
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Frank L
authors.initials: FL
authors.lastname: Heppner
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Marianne
authors.initials: M
authors.lastname: de Visser
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Hans H
authors.initials: HH
authors.lastname: Goebel
authors.affiliation: Departments of Neuropathology (J.R., D.P., F.L.H., H.H.G., W.S.) and Rheumatology and Clinical Immunology (U.S.), Charité Universitätsmedizin Berlin, Germany; and Departments of (Neuro) Pathology (E.A.), Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital (D.S.-M.), and Neurology and Neurophysiology (M.d.V.), Academic Medical Centre, University of Amsterdam, the Netherlands.
authors.forename: Werner
authors.initials: W
authors.lastname: Stenzel