Meta-Analysis
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 28, 2018; 24(20): 2203-2210
Published online May 28, 2018. doi: 10.3748/wjg.v24.i20.2203
Donor-to-recipient gender match in liver transplantation: A systematic review and meta-analysis
Quirino Lai, Francesco Giovanardi, Fabio Melandro, Zoe Larghi Laureiro, Manuela Merli, Barbara Lattanzi, Redan Hassan, Massimo Rossi, Gianluca Mennini
Quirino Lai, Francesco Giovanardi, Fabio Melandro, Zoe Larghi Laureiro, Redan Hassan, Massimo Rossi, Gianluca Mennini, Hepato-bilio-pancreatic and Liver Transplant Unit, Department of Surgery, Sapienza University of Rome, Rome 00161, Italy
Manuela Merli, Barbara Lattanzi, Division of Gastroenterology, Department of Clinical Medicine, Sapienza University of Rome, Rome 00161, Italy
Author contributions: Lai Q makes contribution to conception and design of the study, acquisition of data, analysis and interpretation of data, drafting the article, and final approval; Giovanardi F makes contribution to acquisition of data, analysis and interpretation of data, final approval; Melandro F, Larghi Laureiro Z, Lattanzi B, and Hassan R make contribution to acquisition of data, final approval; Merli M, Rossi M, and Mennini G make contribution to critical revision, final approval.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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: Quirino Lai, MD, PhD, Academic Fellow, Academic Research, Assistant Lecturer, Doctor, Senior Lecturer, Hepato-bilio-pancreatic and Liver Transplant Unit, Department of Surgery, Sapienza University of Rome, Umberto I Policlinic of Rome, Viale del Policlinico 155, Rome 00161, Italy. lai.quirino@libero.it
Telephone: +39-3493020126 Fax: +39-6499701
Received: March 22, 2018
Peer-review started: March 22, 2018
First decision: March 30, 2018
Revised: March 30, 2018
Accepted: May 18, 2018
Article in press: May 18, 2018
Published online: May 28, 2018
ARTICLE HIGHLIGHTS
Research background

Donor-to-recipient gender match has been described as a possible risk factor for post-liver transplant outcomes, mainly when a female-to-male mismatch is done. However, no definitive data exist on this aspect, with only some, mainly monocentric, studies showing somewhat contrasting results. The impact of a meta-analysis on this aspect should be great, mainly in function of the opportunity to clarify a capital element of the organ allocation process in the setting of liver transplantation.

Research motivation

The main aim of the present study is to clarify the role of donor-to-recipient gender mismatching in the setting of liver transplantation. The problem connected to this research is that no definitive clarity exists on the possible risks connected with the use of female donors for transplanting male recipients, although several studies raised on some concerns about this specific matching. The possibility to better clarify this aspect is connected with a safer opportunity to allocate organ during liver transplantation, thus improving the postoperative outcomes of subjects undergoing this type of transplant.

Research objectives

The main objective of the study was to better clarify the role of donor-to-recipient gender mismatch as a possible real risk factor for post-liver transplant graft and patient survival, or if its negative role was caused by several other confounding aspects in the allocation process.

Research methods

Three separate meta-analyses were realized after the systematic collection of all the articles available on English literature focused on the specific argument of donor-to-recipient gender match. First, a meta-analysis focused on the comparison between matched and mismatched cases was done. After this, two separate analyses were done specifically looking at the F-M and M-F mismatches.

Research results

According to the observed results, donor-to-recipient gender mismatch represented a risk factor for post-transplant outcomes, with a 30-fold increased risk for graft loss. When F-M mismatch was specifically investigated, an 83-fold increased risk for graft loss was reported, while such a risk was not present when an M-F mismatch was investigated. Despite the results confirmed the negative role of an F-M mismatch, open questions remained on its effective role, mainly in light of the presence of possible confounding factors potentially justifying these poorer results (i.e., donor and recipient age, recipient disease severity and cause, donor ethnicity, ischemia time duration, and the presence of donor co-morbidities).

Research conclusions

Gender mismatch is a risk factor for poor graft survival after liver transplantation. Female-to-male mismatch represents the worst combination. A particular caution should be taken into account when this combination is present, thus improving the elements to consider during the organ allocation process.

Research perspectives

New studies are needed in this specific setting, with the intent to better clarify the reasons for the poor graft survivals observed in presence of a donor-to-recipient F-M gender mismatch. These studies mainly need to explore the possible confounders potentially being the cause for the reported results.