BACKGROUND: In 2012, a European initiative called Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) was launched to optimise and disseminate diagnostic and management regimens in Europe for children and young adults with rheumatic diseases. Juvenile dermatomyositis (JDM) is a rare disease within the group of paediatric rheumatic diseases (PRDs) and can lead to significant morbidity. Evidence-based guidelines are sparse and management is mostly based on physicians' experience. Consequently, treatment regimens differ throughout Europe. OBJECTIVES: To provide recommendations for diagnosis and treatment of JDM. METHODS: Recommendations were developed by an evidence-informed consensus process using the European League Against Rheumatism standard operating procedures. A committee was constituted, consisting of 19 experienced paediatric rheumatologists and 2 experts in paediatric exercise physiology and physical therapy, mainly from Europe. Recommendations derived from a validated systematic literature review were evaluated by an online survey and subsequently discussed at two consensus meetings using nominal group technique. Recommendations were accepted if >80% agreement was reached. RESULTS: In total, 7 overarching principles, 33 recommendations on diagnosis and 19 recommendations on therapy were accepted with >80% agreement among experts. Topics covered include assessment of skin, muscle and major organ involvement and suggested treatment pathways. CONCLUSIONS: The SHARE initiative aims to identify best practices for treatment of patients suffering from PRD. Within this remit, recommendations for the diagnosis and treatment of JDM have been formulated by an evidence-informed consensus process to produce a standard of care for patients with JDM throughout Europe.

2nd Department of Pediatrics Semmelweis Hospital Budapest Hungary

Alder Hey Children's NHS Foundation Trust Liverpool UK

Centre for Adolescent Rheumatology Institute of Child Health University College London London UK

Department for Immunology Hematology and Pediatric Rheumatology Necker Hospital APHP Institut IMAGINE Paris France

Department of Paediatrics Hacettepe University Faculty of Medicine Ankara Turkey

Department of Paediatrics Meir Medical Center Sackler School of Medicine Tel Aviv University Tel Aviv Israel

Department of Pediatric Immunology Wilhelmina Children's Hospital University Medical Centre Utrecht Utrecht The Netherlands

Department of Pediatric Rheumatology Children's Hospital Helsinki University Central Hospital Helsinki Finland

Division of Allergology Immunology and Rheumatology Department of Pediatrics University Hospital Lausanne Switzerland

Division of Pediatrics Child Development and Exercise Center Wilhelmina Children's Hospital University Medical Center Utrecht Utrecht The Netherlands

Division of Rheumatology The Hospital for Sick Children University of Toronto Toronto Ontario Canada

Paediatric Rheumatology Unit Astrid Lindgren Children's Hospital Karolinska University Hospital Stockholm Sweden

Paediatric Rheumatology Unit Department of Paediatrics and Adolescent Medicine General University Hospital and 1st Faculty of Medicine Charles University Prague Praha Czech Republic

Service of Immunology and Rheumatology Hospital de Pediatría Garrahan Buenos Aires Argentina

Università degli Studi di Genova and Istituto Giannina Gaslini Genoa Italy

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