CD38 and autoimmune hemolytic anemia: Emerging therapies for autoimmune hemolytic anemia target various steps in the pathogenesis of AIHA and include B-cell-directed therapies with BTK inhibitors, PI3K inhibitors, mTOR inhibitors, phagocytosis inhibition with the Syk inhibitor, FcRn inhibitors, plasma cell-directed therapies with proteasome inhibitors and CD38 monoclonal antibodies, and complement inhibition.