Retrospective Cohort Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 14, 2016; 22(30): 6925-6935
Published online Aug 14, 2016. doi: 10.3748/wjg.v22.i30.6925
Risk factor for ischemic-type biliary lesion after ABO-incompatible living donor liver transplantation
Jun Bae Bang, Bong-Wan Kim, Young Bae Kim, Hee-Jung Wang, Hyun Yeong Lee, Joohyun Sim, Taegyu Kim, Kyeong Lok Lee, Xu-Guang Hu, Wei Mao
Jun Bae Bang, Bong-Wan Kim, Hee-Jung Wang, Joohyun Sim, Taegyu Kim, Kyeong Lok Lee, Xu-Guang Hu, Wei Mao, Department of Liver Transplantation and Hepatobiliary Surgery, Ajou University School of Medicine, Suwon 443-749, South Korea
Young Bae Kim, Department of Pathology, Ajou University School of Medicine, Suwon 443-749, South Korea
Hyun Yeong Lee, Department of Biostatistics, Ajou University School of Medicine, Suwon 443-749, South Korea
Author contributions: Bang JB collected and analyzed the data and wrote the manuscript; Kim BW designed and supervised the study, and wrote the manuscript; Kim YB performed pathological examination and analysis; Wang HJ supervised and conducted the study; Lee HY analyzed the data for statistics; Sim J, Kim T, Lee KL, Hu XG and Mao W offered technical and material support; and all authors have read and approved the final version of the manuscript.
Supported by An Academic-Grant for Scientific Research from Astellas Pharma Korea, Inc.
Institutional review board statement: This study was reviewed and approved by institutional review board of the Ajou University Hospital (MED-MDB-15-061).
Informed consent statement: This retrospective study was performed under the IRB approval and all data were de-identified for statistical analysis. A waiver of informed consent could be justified for this retrospective study.
Conflict-of-interest statement: The authors declare no conflict of interests.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at drbwkim@ajou.ac.kr. This retrospective study obtained clinico-pathological data from institutional anonymized database which have very low risk of patient identification.
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: Bong-Wan Kim, MD, PhD, Department of Hepatobiliary Surgery and Liver Transplantation, Ajou University School of Medicine, san 5, Wonchon-dong, Youngtong-gu, Suwon 443-749, South Korea. drbwkim@ajou.ac.kr
Telephone: +82-31-2195200 Fax: +82-31-2195755
Received: April 11, 2016
Peer-review started: April 13, 2016
First decision: May 12, 2016
Revised: June 7, 2016
Accepted: June 28, 2016
Article in press: June 28, 2016
Published online: August 14, 2016
Abstract

AIM: To evaluate the risk factors for ischemic-type biliary lesion (ITBL) after ABO-incompatible (ABO-I) adult living donor liver transplantation (ALDLT).

METHODS: Among 141 ALDLTs performed in our hospital between 2008 and 2014, 27 (19%) were ABO-I ALDLT and 114 were ABO-identical/compatible ALDLT. In this study, we extensively analyzed the clinico-pathological data of the 27 ABO-I recipients to determine the risk factors for ITBL after ABO-I ALDLT. All ABO-I ALDLT recipients underwent an identical B-cell depletion protocol with preoperative rituximab, plasma exchange (PE), and operative splenectomy. The median follow-up period after transplantation was 26 mo. The clinical outcomes of the 27 ABO-I ALDLT recipients were compared with those of 114 ABO-identical/compatible ALDLT recipients.

RESULTS: ITBL occurred in four recipients (14.8%) between 45 and 112 d after ABO-I ALDLT. The overall survival rates were not different between ABO-I ALDLT and ABO-identical/compatible ALDLT (P = 0.303). Among the ABO-I ALDLT recipients, there was no difference between patients with ITBL and those without ITBL in terms of B-cell and T-cell count, serum isoagglutinin titers, number of PEs, operative time and transfusion, use of graft infusion therapy, or number of remnant B-cell follicles and plasma cells in the spleen. However, the perioperative NK cell counts in the blood of patients with ITBL were significantly higher than those in the patients without ITBL (P < 0.05). Preoperative NK cell count > 150/μL and postoperative NK cell count > 120/μL were associated with greater relative risks (RR) for development of ITBL (RR = 20 and 14.3, respectively, P < 0.05).

CONCLUSION: High NK cell counts in a transplant recipient’s blood are associated with ITBL after ABO-I ALDLT. Further research is needed to elucidate the molecular mechanism of NK cell involvement in the development of ITBL.

Keywords: Liver transplantation, ABO-incompatibility, Ischemic-type biliary lesion, Natural killer cell

Core tip: Despite application of B-cell depletion protocols for ABO-incompatible (ABO-I) adult living donor liver transplantation (ALDLT), ischemic-type biliary lesion (ITBL) remains one of the major complications associated with graft failure. However, no study could yet evaluate the risk factors affecting development of ITBL after ABO-I ALDLT because of limited data availability. We have extensively analyzed clinico-pathological data from ABO-I ALDLT patients in this study to identify the risk factors for ITBL. Our results suggest that NK cells in the recipient’s blood may be associated with development of ITBL after ABO-I ALDLT, which was supported by serological and pathological findings.