Living related liver transplantation in patients with ABO incompatibility

Management of Anti-allogeneic Antibody Elimination by Apheresis in Living Donor Liver Transplantation

In this study, we report on the indications and efficacy of the elimination of antiallogeneic antibodies in living donor liver transplant recipients. Seven patients incompatible with the ABO-blood type were subjected to apheresis before transplantation. The procedure resulted in titers being decreased to less than a score of 8. After transplantation, apheresis was also performed in 6 cases and continuous hemodiafiltration in 1 case. In addition, three out of 11 ABO-blood type incompatible recipients were administered anti-CD20 antibody (rituximab). Two crossmatch positive patients were subjected to apheresis before transplantation, and in these cases the titers were reduced to less than a score of 2. Moreover, these two patients had no acute rejections after transplantation. We concluded that apheresis is effective for preventing acute rejection induced by pre-existing anti-A and/or anti-B antibodies, as well as antidonor specific antibodies, but is not effective in some patients who had accelerated humoral rejection.

Chimerism in the immunohematology laboratory in the molecular biology era

Dual or multiple cell populations, induced by chimeras, have been the subject of many studies. This long-standing fascination with chimeras has revealed a good deal of knowledge about human inheritance. Although historically most chimeras were caused by natural events, certain current medical intervention therapies are increasing the number of situations that can lead to a mixed cell population, that is, the chimeric condition, in humans. Medical therapies such as transfusion, stem cell transplantation, kidney transplantation, and artificial insemination induce temporary and sometimes permanent chimeras. Such natural or therapeutically induced presentations of chimerism can present challenging issues to the clinical immunohematology laboratory with regard to interpretation of results and subsequent patient management. The purpose of this review was to highlight some of these chimeric states and hypothesize how testing DNA from various tissues can cause apparent discrepancies between phenotype and genotype results.

Successful ABO-incompatible pediatric liver transplantation utilizing standard immunosuppression with selective postoperative plasmapheresis

Transplanting blood group A, B, or O (ABO)-incompatible (ABO-I) liver grafts has resulted in lower patient and graft survival with an increased incidence of vascular and biliary complications and rejection. We report that, without modification of our standard immunosuppression protocol, crossing blood groups is an acceptable option for children requiring liver transplantation. In our study, ABO-I liver grafts -- regardless of recipient age -- have comparable long-term survival (mean follow-up of 3.25 yr) with ABO-compatible grafts without any difference in rejection, vascular or biliary complications. From January 1, 1999 to October 1, 2005, we studied 138 liver transplants in 121 children: 16 (13.2%) received an ABO incompatible liver allograft. One-year actuarial patient survival for ABO-matched grafts vs. ABO-I grafts was 93.0% and 100%, respectively, whereas graft survival was 83.4% and 92.3%. Additionally, 6 of 16 (37.5%) ABO-I transplanted children had 8 rejection episodes, whereas 47 patients (44.8%) had 121 rejection episodes in the ABO-compatible group. There were no vascular complications and 2 biliary strictures in the ABO-I group. Plasmapheresis was not used for pretransplantation desensitization and was only required in 1 posttransplantation recipient. No child was splenectomized. Six of the 16 children were older than 13 yr of age, suggesting the possibility of successfully expanding this technique to an older population. In conclusion, our outcomes may support the concept of using ABO-I grafts in a more elective setting associated with split and living donor liver transplants.

Liver transplants from living related donors

Liver transplantation from living related donors was unthinkable until recently, when the safety of modern hepatic surgery became widely appreciated. The first step was the successful demonstration that parts of livers could be transplanted. This technique, termed reduced-size liver transplantation, evolved into reliable procedures to allow parents to donate small parts of their livers to small children. More recently, right hepatectomy, in which up to 70% of the liver is resected for donation, has been performed in adults. As the demand for liver transplantation continues to increase, the development of ethically sound, medically and surgically optimal programs for routine use of living donors has become essential. This chapter provides a broad overview of the evolution and current state of liver transplantation with living donors.