Abstract • 108

A ten month-old-boy presented with a severe intravascular hemolysis. He had no past history, except for a recent bronchitis treated with Amoxycillin. Initial examination revealed extreme palor, middle enlargement of liver and spleen and massive hemoglobinuria. Hemoglobin value and reticulocyte count were 4,2 g/dl and 441×109/L respectively, with normal leucocyte and platelet values. Direct antiglobulin test was positive for a warm-reacting IgA antibody alone. Intravenous methylprednisolone (4 mg/kg/d) was immediately started, but the hemolysis remained severe, needing 2 packed red blood cell transfusions per day. On days 4, 6 and 8, he received high dose of methylprednisolone (1 g/1,73 m2), followed by a daily dose of prednisolone (3 mg/kg/d). He had to be transfused ninefold during the first 18 days, but the hemolysis progressively decreased. He remained transfusion independant after two months, and steroids were tapered. No infection, immunodeficiency or malignancy was found. IgA autoimmune hemolysis is rare in childhood, and often results in severe intravascular hemolysis. Its management does not differ from more usual autoimmune anemia associated with IgG, and consists in steroids, and immunosuppressive drugs if necessary ; splenectomy can be required, and is usually curative. IgA antibody is usually associated with IgG or IgM antibody and/or complement ; its role in the pathophysiology of the hemolysis remains is not elucidated.