Cost Effectiveness of ABO-incompatible Kidney Transplantations

Field: Medicine (Health Sciences)

Historically, ABO-incompatible kidney transplantations have only been performed after several preoperative sessions of plasmapheresis to remove existing anti-A or anti-B antibodies. Plasmapheresis was followed by splenectomy and a conventional triple-drug immunosuppressive protocol reinforced with antilymphocyte globulin and B cell-specific drugs such as cyclophosphamide or deoxyspergualin to prevent the rebound of antibodies (1). However, because splenectomy, a reinforced immunosuppressive protocol and multiple sessions of plasmapheresis, carries significant morbidity and even mortality, ABO-incompatible living donor transplantations have with few exceptions only been performed in centers where no other options besides live donor transplantation have been available. Recently, however, there has been a renewed interest in ABO-incompatible live donor kidney transplantations (2, 3, 4). This is partly due to the improvement in results that has been reported from Japan (5). More importantly, it is due to a desire to further expand the living donor pool at a time when there exists an increasing discrepancy between the number of patients on the waiting list and the number of organs available for transplantation. The paper by Schwartz et al. (6) in this issue on complications, resource utilization, and cost of ABO-incompatible living donor kidney transplantations is therefore very timely. Schwartz and colleagues found that overall surgery-related complications and resource utilization were increased in ABO-incompatible transplantations, primarily owing to the desensitization protocol and antibody-mediated rejections. Interestingly, they found a significant correlation between antibody-mediated rejections and surgery-related complications. The total increase in costs for an ABOincompatible kidney transplantation was approximately US$38,000. Nevertheless, ABO-incompatible transplantations are of course cost-effective when compared with maintaining the patient on dialysis while waiting for a blood group–compatible, deceased donor kidney. These are very important data but it should be pointed out that the study was performed in the United States and the protocol used for ABO-incompatible transplantations in the United States differs significantly from that used in Europe. The European protocol that was introduced in 2001 (3) utilizes antigen-specific immunoadsorption (GlycoSorb, Glycorex Transplantation AB, Lund, Sweden) rather than plasma exchange to remove existing anti-A or anti-B antibodies. Because with antigen-specific immunoadsorption nothing but the blood group antibodies are removed from plasma, none of the complications normally associated with multiple sessions of plasmapheresis are observed. Furthermore, anti T-cell antibody induction therapy is not used and the monoclonal humanized anti-CD20 antibody rituximab is used instead of splenectomy. More than 90 ABO-incompatible transplantations have now been performed with the European protocol, primarily in Sweden (7, 8) and Germany (9), but also in the United Kingdom, the Netherlands, Switzerland, and Greece. The results have been excellent, with no early graft losses and no specific complications that can be related to the procedure. Notably there have been no humoral rejections. Obviously the costs related to plasma exchange, surgical, and infectious complications, and antibody-mediated rejections have been much reduced with this protocol. Unfortunately, however, these savings are easily offset by the cost for the antigen-specific immunoadsorbers. With the present pricing, the cost for immunoadsorption (apheresis and immunoadsorbers) ranges from US$18,000 to US$36,000, depending on the number of apheresis sessions needed to remove the blood group antibodies. Even though the procedure is still cost-effective when compared with maintaining the patient on dialysis, it is still a significant problem for the specific center. Thus, in spite of the recent improvements in results, many centers are presently hesitant to adopt ABO-incompatible programs because of lack of funding.