The aim of this prospective study was to evaluate the activity, safety and the duration of the response of low dose rituximab associated with standard oral prednisone as first line therapy in newly diagnosed warm autoimmune hemolytic anemia and cold hemagglutinin disease, and as second line therapy in warm autoimmune hemolytic anemia relapsed after standard oral prednisone. Further aim was to correlate the clinical response to biological parameters (cytokine and anti-erythrocyte antibody production in cultures).