Svea Horn1, Kirsten Minden2, Fabian Speth3, Tobias Schwarz4, Frank Dressler5, Nadine Grösch1, Johannes-Peter Haas6, Claas Hinze7, Gerd Horneff8, Anton Hospach9, Tilmann Kallinich10, Jens Klotsche1, Katharina Köstner6, Christian Meisel11, Martina Niewerth1, Prasad Thomas Oommen12, Catharina Schütz13, Frank Weller-Heinemann14, Nadine Unterwalder11, Claudia Sengler15. 1. German Rheumatism Research Center, Leibniz Institute, Berlin, Germany. 2. German Rheumatism Research Center, Leibniz Institute, and Department of Rheumatology and Clinical Immunology, Charité Universitätsmedizin, Berlin, Germany. 3. Universitätsmedizin Rostock, Kinder- und Jugendklinik, Rostock, Germany. 4. Department of Paediatric Rheumatology, St. Josef-Stift, Sendenhorst, Germany. 5. Department of Paediatric Pneumology, Allergology and Neonatology, Children's Hospital, Medical School, Hannover, Germany. 6. German Center for Paediatric and Adolescent Rheumatology, Garmisch-Partenkirchen, Germany. 7. Department of Paediatric Rheumatology and Immunology, University Hospital, Münster, Germany. 8. Center for General Paediatrics and Neonatology, Asklepios Klinik Sankt Augustin, and Department of Paediatric and Adolescent Medicine, University Hospital, Cologne, Germany. 9. Center for Paediatric Rheumatology, Olgahospital, Stuttgart, Germany. 10. German Rheumatism Research Center, Leibniz Institute, Berlin, and Charité Universitätsmedizin Berlin, Paediatric Pneumology, Immunology and Critical Care Medicine and SPZ (Center for Chronically Sick Children), Berlin, Germany. 11. Labor Berlin - Charité Vivantes GmbH, Berlin, Germany. 12. Heinrich-Heine University Düsseldorf, Medical Faculty, Clinic of Paediatric Haematology, Oncology and Clinical Immunology, Düsseldorf, Germany. 13. Department of Paediatrics, Medical Faculty Carl Gustav Carus, Technical University, Dresden, Germany. 14. Prof.-Hess-Kinderklinik, Bremen, Germany. 15. German Rheumatism Research Center, Leibniz Institute, Berlin, Germany. sengler@drfz.de.
Abstract
OBJECTIVES: To describe a German cohort of patients with juvenile dermatomyositis (JDM) and to evaluate clinical manifestations, disease course and prognosis in JDM patients with a certain myositis-specific autoantibody. METHODS: Cross-sectional data on patients with JDM documented in the National Paediatric Rheumatologic Database in Germany between 2014 and 2016 were analysed. In a subgroup of the cohort, MSAs were determined with a commercial multiplex array, and a retrospective chart review was conducted to specify the clinical phenotype and patient outcome. RESULTS: The total cohort consisted of 196 patients with JDM (mean age 12.2±4.0 years, mean disease duration 5.1±3.8 years, 70% female). Apart from typical skin changes and muscle weakness, 41% of patients also had arthritis and/or contractures, 27% had calcinosis and approximately 10% had interstitial lung disease. Immunoblot testing was performed on the sera of 91 (46%) patients, detecting MSAs in 44% of patients. Patient groups with specific MSAs differed in clinical characteristics such as calcinosis, dysphagia, and lung and joint involvement. The extent of muscle weakness evaluated by the Childhood Myositis Assessment Scale was significantly associated with an increased level of creatine kinase. Patients with anti-MDA5 were particularly affected by polyarthritis of the small joints. After 5 years, 51 patients of the MSA cohort (56.0%) achieved an inactive disease state, 12/51 (23.5%) were off therapy. CONCLUSIONS: Patients with JDM in Germany show a broad spectrum of clinical manifestations that can be grouped into homogeneous groups using MSA, which also helps to predict the course and prognosis of the disease.
OBJECTIVES: To describe a German cohort of patients with juvenile dermatomyositis (JDM) and to evaluate clinical manifestations, disease course and prognosis in JDM patients with a certain myositis-specific autoantibody. METHODS: Cross-sectional data on patients with JDM documented in the National Paediatric Rheumatologic Database in Germany between 2014 and 2016 were analysed. In a subgroup of the cohort, MSAs were determined with a commercial multiplex array, and a retrospective chart review was conducted to specify the clinical phenotype and patient outcome. RESULTS: The total cohort consisted of 196 patients with JDM (mean age 12.2±4.0 years, mean disease duration 5.1±3.8 years, 70% female). Apart from typical skin changes and muscle weakness, 41% of patients also had arthritis and/or contractures, 27% had calcinosis and approximately 10% had interstitial lung disease. Immunoblot testing was performed on the sera of 91 (46%) patients, detecting MSAs in 44% of patients. Patient groups with specific MSAs differed in clinical characteristics such as calcinosis, dysphagia, and lung and joint involvement. The extent of muscle weakness evaluated by the Childhood Myositis Assessment Scale was significantly associated with an increased level of creatine kinase. Patients with anti-MDA5 were particularly affected by polyarthritis of the small joints. After 5 years, 51 patients of the MSA cohort (56.0%) achieved an inactive disease state, 12/51 (23.5%) were off therapy. CONCLUSIONS: Patients with JDM in Germany show a broad spectrum of clinical manifestations that can be grouped into homogeneous groups using MSA, which also helps to predict the course and prognosis of the disease.