Plasma exchange in autoimmune hemolytic anemia (AIHA).

Plasma exchange therapy in autoimmune hemolytic anemia (AIHA) was used in four patients (two with warm hemolytic anemia and two with cold hemolytic anemia). The size of each plasma exchange approximated 1 plasma volume; three consecutive daily exchanges removed 80-90% of the immunoglobulins--immunoglobulin G (IgG) and immunoglobulin M (IgM)-, complement (C3, C4), and reduced antibody titers. Transfusion requirements dramatically decreased after plasma exchange in each case. In two patients, red blood cell (RBC) survival studies were performed to more accurately assess the effect of plasma exchange therapy, since steroid and/or immunosuppressive therapy was given concomitantly. In one case of cold AIHA, homologous 51Cr-RBC were injected 4 days prior to plasma exchange and repeat injection (same donor) following completion of plasma exchange. The survival curve prior to plasma exchange therapy had a T 1/2 = 7.8 days (r = -0.988) and after plasma exchange therapy had a T 1/2 = 20.4 days (r = 0.925). RBC survival studies using homologous 51Cr-RBC were also performed in a patient with warm AIHA. The survival curve before plasma exchange had a T 1/2 = 2 days (r = -0.95), and postplasma exchange a T 1/2 = 1.8 days (r = -0.91). Plasma exchange therapy seems to have a beneficial effect in cold rather than warm autoimmune hemolytic anemia.