[Panniculitis and macrophage activation syndrome in a child with lupus erythematosus].

INTRODUCTION: Panniculitis is rarely presented in the course of systemic lupus erythematosus. When it occurs, it is mainly related to lupus profundus. However, when panniculitis is associated with a reactive hemophagocytic syndrome, panniculitis could be linked to this hemophagocytosis reaction. CASE REPORT: We report a case of an 11-year-old girl treated for several years for systemic lupus erythematosus, who simultaneously presented panniculitis and an hemophagocytic syndrome. The reality of both diagnoses was based on the analysis of biological and histological data. Therapy with immunosuppressive drugs led to relief of the symptoms. DISCUSSION: We emphasize our discussion on the pathophysiology of lupus profundus and hemophagocytosis with regards to the role of cytokines and circulating immune complexes in both diseases. They may enhance the hypodermal necrosis observed in lupus profundus and induce macrophage cell dysregulation through cytotoxic cells known in hemophagocytosis. The immunomodulative action of immunosuppressive therapy with inhibition of cells involved in immune response, may explain its efficacy.