Cryofiltration apheresis for major ABO-incompatible kidney transplantation

The barrier of ABO-incompatible kidney transplantation is the presence of anti-A and anti-B antibodies in the recipient's circulating blood. Double filtration plasmapheresis (DFPP) is usually used to eliminate those antibodies. We tried cryofiltration apheresis (CRYO) in 2 recipients. Patient 1 was a 45-year-old male with B, Rh(+). The titers of IgM anti-A antibody were only reduced from x64 to x32 by the end of 3 sessions of standard CRYO. Renal allografting was not performed. Case 2 was a 29-year-old male with B, Rh(+). CRYO was introduced for 3 sessions. The initial IgM and IgG titers were x128 and negative, respectively. The standard CRYO system was modified by temperature, treated volume, and filter pore size. The IgM anti-A antibody titer was markedly reduced to x2 after the final session of CRYO. The donor was a 56-year-old father with A, Rh(+). Tacrolimus, azathioprine, methylprednisolone, and antilymphocyte globulin were used as the introductory immunosuppression therapy.