P052 Juvenile dermatomyositis, a multi-faceted disease

Abstract Background Dermatomyositis is a rare disease. In children, the incidence is 2–3 per million habitants. It is a serious disease whose mortality is < 5% but whose complications and long-term prognosis remain pejorative for some children. The objective is to report the epidemiological, clinical, therapeutic options and the course of a retrospective series carried out at the CHU pediatric center of Sétif (Algeria) comprising 8 cases of juvenile dermatomyositis. Methods The mean age of onset is 7.7 years (0–15.5 years), The sex ratio was 0.1; The diagnosis delay averaged at 4, 4 months. At disease onset, 100% had rash, 84% a eyelids telangiectasias, 40% Gottron nodules, 90% muscular weakness, 40% arthritis, 13% fever, and 25% dysphagia. The muscular enzymes were increased in 8 cases. The DNA antibodies were present in one patient with myositis overlap, NXP was positive in one child. The electromyogram is myogenic in all patients. Seven patients underwent a histopathological exam, showing interstitial and parenchymal myositis. Treatment regimens were variable depending on the severity of the disease onset. All children were treated with steroids as the first line. Methotrexate was prescribed in 5 cases (62.5%). The immunoglobulin was indicated in 2 cases. The failure to thrive was observed in 2 (25%), and one child died following aspiration pneumonia. Results The dermatomyositis diagnosis is based on the Bohan and Peter criteria. The clinical characteristics of our series are in line with the literature data with a predominance of cutaneous and muscular involvement. However, some specificities are individualized: a case of overlapping myositis with lupus, a case of extensive calcinosis. The treatment was based on corticosteroids and methotrexate. Conclusion Dermatomyositis juvenile is a rare disease with a pejorative prognosis requiring a multidisciplinary management.