Our first experiences in applying an original method for removal of ABO-isoagglutinins in ABO-incompatible kidney recipients Naša prva iskustva u primeni originalne metode za snižavanje titra ABO izoaglutinina kod ABO inkompatibilnih transplantacija bubrega

Background/Aim. Due to improved methods for removal of ABO isoagglutinins and novel immunosuppressive protocols, short and long term outcome in blood group incompatible is similar to blood group compatible kidney transplantation. The aim of this study was to determine the efficacy of our original method for removal of ABO isoagglutinins from the blood in ABO-incompatible kidney allograft recipients. Method. Between 2006 and 2008 twelve patients were transplanted from ABO incompatible living donors. Titers of ABO isoagglutinins were 4–128 (IgG). Immunosuppressive therapy started 14 days before kidney transplantation with rituximab, followed by a triple therapy (prednisone + tacrolimus + mycophenolate mofetil) and the first plasma exchange (PE) procedure, in which one plasma volume was substituted with albumin and saline on day 7 before transplantation. For selective extracorporeal immunoadsorption, the removed plasma was mixed with donor blood type filtered red blood cells, centrifuged and the supernatant separated and preserved. In the next PE procedure, the removed plasma was replaced with immunoadsorbed plasma, and so on. Titers of ABO agglutinins, renal allograft function and survival were followed-up. Results. The pre-transplant treatment consisting of 1–5 PE procedures and immunosuppressive therapy resulted in target ABO agglutinins titers below 4. During a 10–24 month follow-up three patients had an early acute rejection, one patient acute rejection and hemolytic anemia, two patients surgical complications and one of them lost his graft. In the post-transplant period, the titers of ABO antibodies remained below 4. All the patients had stable kidney allograft function with mean serum creatinine ±SD of 129 ± 45 μmol/l at the end of the study. Conclusion. Our method for removal of ABO antibodies was effective in a limited series of patients and short-term follow-up.