atypical presentation of juvenile dermatomyositis: about one case

Juvenile dermatomyositis is a multisystem immune-mediated disease that affects the skin, muscles and gastro-intestinal tract. Elevation of serum muscle enzymes, electromyogram findings and muscle biopsy are helpful to confirm the diagnosis of dermatomyositis. The goal of this article is to describe an unusual presentation of juvenile dermatomyositis, associated to celiac disease, with atypical exploration and unexpected evolution to extensive calcinosis. Nora, 14 years old, is followed since the age of 10 for celiac disease successfully treated with a gluten-free diet. At 11 years she is hospitalized because of arthralgia and myalgia. The physical examination shows erythematous facial rash, Gottron papules in metacarpo-phalangian articulations, and desquamatives lesions of elbows. She presents ankles, knees and wrists arthritis with lumbalgia. The diagnosis of dermatomyositis is suspected. Laboratory findings show a moderate inflammation, non auto-immune signs, increased level of muscular enzymes, without any abnormalities neither in the electromyogram nor in the biopsy. The diagnosis of dermatomyositis is confirmed. The patient is treated with high doses of oral corticotherapy, articular kinesi-therapy and gluten-free diet. The outcome was satisfactory, but an extensive calcinosis appeared after 3 years. Dermatomyositis and celiac disease is a rare association; only a few cases have been reported. They have common auto-immune condition that can explain this association. Regarding the nonspecific results of the electromyogram and the muscular biopsy, it can be due to the choice of an area which is not involved. The calcinosis is unusual in this type of monocyclic and stabilized involvement. It can appear due to the poor efficacy of oral corticoids prescribed in the context of malabsorption