Observational Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Transplant. Dec 24, 2015; 5(4): 329-337
Published online Dec 24, 2015. doi: 10.5500/wjt.v5.i4.329
Excellent long term patient and renal allograft survival after ABO-incompatible kidney transplantation: Experience of one center
Christina Melexopoulou, Smaragdi Marinaki, George Liapis, Chrysanthi Skalioti, Maria Gavalaki, George Zavos, John N Boletis
Christina Melexopoulou, Smaragdi Marinaki, Chrysanthi Skalioti, John N Boletis, Nephrology Department and Renal Transplantation Unit, Laiko Hospital, 11527 Athens, Greece
George Liapis, 1st Department of Pathology Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
Maria Gavalaki, Blood Transfusion Center-National Reference Center for Congenital Haemorrhagic Disorders, Laiko Hospital, 11527 Athens, Greece
George Zavos, Renal Transplantation Unit, Laiko Hospital, 11527 Athens, Greece
Author contributions: Melexopoulou C collected and analyzed the data and wrote the following sections: “Materials and Methods” and “Results”; Marinaki S analyzed and evaluated the data and wrote the following sections: “Introduction” and “Discussion”; Liapis G evaluated the histopathologic findings and wrote the following sections: “Biopsies” and “Histopathologic evaluation - Acute rejections”; Skalioti C contributed to the collection of data; she also wrote the “Abstract” and contributed to the writing of the following sections: “Materials and Methods” and “Results”; Gavalaki M analyzed the blood samples; Zavos G contributed to the final revision of the paper; Boletis JN established the ABO-incompatible program in Greece and continues to be the supervisor of the program, he also did the final revision of the paper.
Institutional review board statement: The scientific council of “Laiko” General Hospital of Athens was informed for the study.
Informed consent statement: All participants provided informed consent prior to enrollment in the study.
Conflict-of-interest statement: The authors declare that there is no conflict of interests regarding the publication of this paper.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Christina Melexopoulou, MD, Nephrology Department and Renal Transplantation Unit, Laiko Hospital, 17 Ag., Thoma Street, 11527 Athens, Greece. xmelexopoulou@yahoo.gr
Telephone: +30-210-7456351 Fax: +30-21-32061243
Received: August 9, 2015
Peer-review started: August 11, 2015
First decision: September 21, 2015
Revised: October 10, 2015
Accepted: November 23, 2015
Article in press: November 25, 2015
Published online: December 24, 2015

AIM: To investigate the long-term results of ABO-incompatible (ABOi) kidney transplantation in a single center in Greece.

METHODS: Thirty consecutive ABOi kidney transplantations were performed from June 2005 to December 2013. All patients received rituximab one month prior to transplantation. Immunoadsorption therapy was performed for the removal of anti-A/B IgG antibodies until the titer was ≤ 1:16. Additional apheresis sessions were performed post-operatively. Intravenous immunoglobulin and oral immunosuppression consisting of tacrolimus (TAC) in combination with either everolimus or mycophenolate acid was administered. We compared the long term results of our ABOi group to those of a matched group of 30 ABO compatible (ABOc) living kidney recipients with similar baseline characteristics. The ABOc recipients received an immunosuppressive regimen consisting of TAC and mycophenolate acid. All patients in both groups received induction therapy with Basiliximab or Daclizumab, whereas corticosteroids were instituted on the day of surgery. During the follow-up period, indication biopsies were performed and interpreted by an experienced nephropathologist. The parameters we analyzed included the following: Donor/recipient age, gender, blood type, human leukocyte antigen mismatches, panel reactive antibodies, primary cause of renal failure, mean time on dialysis, immunosuppressive regimen, patient survival, graft outcome, incidence of rejections, surgical and infectious complications.

RESULTS: The mean follow-up period was 6 years (range 1 to 9 years). A mean of 5.0 ± 3.0 (range 0-14) pre-transplant immunoadsorptions were required in order to reach the target titer. Patient survival in ABOi group in comparison to ABOc group at 1, 3, 5 and 8 years did not differ significantly (100% vs 100%, 96% vs 100%, 92% vs 100% and 92% vs 100%, P = ns). Additionally, graft survival was similar in the two groups at the same time points (100% vs 100%, 96% vs 96%, 92% vs 96% and 81% vs 92%, P = ns). The mean serum creatinine and the estimated glomerular filtration rate by the modification of diet in renal disease formula at 1, 3, 5 and 8 years did not differ significantly between ABOi and ABOc group. None of the patients in the ABOi group developed acute or chronic antibody-mediated rejection evidenced by histological signs. Four patients (13.3%) in the ABOi group and 3 (10%) in the ABOc group experienced acute cellular rejection, which was treated successfully in all cases. Bacterial and viral infections were also similar between the two groups.

CONCLUSION: ABOi kidney transplantation is a safe and effective alternative that enables kidney transplantation in countries with unacceptably long deceased-donor waiting lists.

Keywords: ABO-incompatible, Kidney, Transplantation, Renal transplant, Everolimus, Immunoadsorption

Core tip: These excellent long term results further establish ABO-incompatible (ABOi) kidney transplantation as a safe and effective therapeutic strategy for the management of end-stage renal disease patients. Various immunosuppressants including Everolimus could be potentially selected based on patient’s profile. ABOi kidney transplantation could contribute to the enlargement of the living donor pool, particularly in countries with organ shortage.