title: Clinical features and disease course of patients with juvenile dermatomyositis.
abstract: OBJECTIVE
  To describe the clinical features and course of a cohort of patients with juvenile dermatomyositis (JDM) at a tertiary referral pediatric centre in Australia and examine changes in diagnostic and therapeutic approach over time.
  
  
  METHODS
  Retrospective review of patients diagnosed with JDM at the Royal Children's Hospital, Melbourne, between 1989 and 2010.
  
  
  RESULTS
  Fifty-seven patients were identified. The female : male ratio was 2 : 1 and median age at diagnosis was 7.1 years (2.2-15.3). At diagnosis, 95% had weakness, all had typical rash and 68% had nailfold capillary changes. Calcinosis was not present in any patients at diagnosis and occurred in 18% over time. Creatine kinase, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase and aldolase levels were abnormal in 65%, 92%, 88%, 58% and 100%, respectively. Magnetic resonance imaging (MRI) was abnormal in 97% of patients, electomyograph (EMG) in 83% and muscle biopsy in all four patients in whom it was performed. MRI was used in 86% (24/28) of patients diagnosed after 2000. Muscle biopsy was used in four and EMG in no patients over the same period. Treatment used throughout the disease course included oral steroids (93%), high-dose pulse intravenous steroids (82%), methotrexate (63%), intravenous immunoglobulin (32%) and cyclosporin (18%). The disease was monophasic in 46.7% (21/45), polyphasic in 17.7% (8/45) and chronic in 35.5% (16/45).
  
  
  CONCLUSIONS
  Australian patients with JDM have similar characteristics to previously described cohorts. In practice, MRI has replaced the invasive diagnostic tests included in the Bohan and Peter criteria for the diagnosis of JDM. The early use of disease-modifying anti-rheumatic drugs has become the most common treatment approach.
authors.affiliation: Department of General Medicine, Rheumatology Service, Royal Children's Hospital, Melbourne, Victoria, Australia.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Gowdie
authors.forename: Roger C
authors.initials: RC
authors.lastname: Allen
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Kornberg
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Akikusa
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003882:Dermatomyositis / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D004059:Diffusion of Innovation; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012219:Rheumatology / Q000379:methods* / Q000639:trends; D062606:Tertiary Care Centers; D013997:Time Factors; D014739:Victoria / Q000453:epidemiology
chemical_list: D018501:Antirheumatic Agents
keywords: Australasia; juvenile dermatomyositis