title: Juvenile dermatomyositis: A report of three cases.
abstract: Juvenile dermatomyositis (JDM), an autoimmune idiopathic myositis, is characterized by rash and proximal muscle weakness. Immunohistopathology typically shows perivascular inflammatory infiltrate with predominance of CD4+ T lymphocytes, perifascicular atrophy, and upregulation of major histocompatibility complex class I. JDM has been attributed to a humoral-driven muscle microangiopathy probably implicating the type I interferon pathway. Tubulo-reticular inclusions present in endothelial cell of muscle are biomarkers of interferon exposure, and so may be an indirect data of this myopathy especially in the absence of rash and inflammatory infiltrate. We report on three patients in which electron microscopy solves the differential diagnosis among infantile myositis showing peculiar inclusions.
authors.affiliation: a Department of Biomedical and Neuromotor Sciences , University of Bologna , Bologna , Italy.
authors.forename: V
authors.initials: V
authors.lastname: Papa
authors.affiliation: b Department of Pediatric Emergency, S. Orsola-Malpighi Hospital , Bologna , Italy.
authors.forename: B
authors.initials: B
authors.lastname: Romanin
authors.affiliation: c Department of Medical and Surgical Sciences , University of Bologna , Bologna , Italy.
authors.forename: R
authors.initials: R
authors.lastname: Bergamaschi
authors.affiliation: d Operative Unit of Child Neuropsychiatry, S. Orsola-Malpighi Hospital , Bologna , Italy.
authors.forename: D M
authors.initials: DM
authors.lastname: Cordelli
authors.affiliation: a Department of Biomedical and Neuromotor Sciences , University of Bologna , Bologna , Italy.
authors.forename: R
authors.initials: R
authors.lastname: Costa
authors.affiliation: e Operative Unit of Anatomy, Pathological Histology, S. Orsola-Malpighi Hospital , Bologna , Italy.
authors.forename: L Badiali
authors.initials: LB
authors.lastname: De Giorgi
authors.affiliation: a Department of Biomedical and Neuromotor Sciences , University of Bologna , Bologna , Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cenacchi
mesh_terms: D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003882:Dermatomyositis / Q000473:pathology*; D003937:Diagnosis, Differential; D042241:Early Diagnosis; D042783:Endothelial Cells / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D018482:Muscle, Skeletal / Q000648:ultrastructure*; D011237:Predictive Value of Tests
keywords: Dermatomyositis; infantile myosytis; tubulo-reticular inclusions