Review: Recent advances in liver transplantation

Liver transplant is a life-saving treatment with 1-year and 5-year survival rates of 90% and 70%, respectively. However, organ demand continues to exceed supply, such that many patients will die waiting for an available organ. This article reviews for the general gastroenterologist the latest developments in the field to reduce waiting list mortality and maximise utilisation of available organs. The main areas covered include legislative changes in organ donation and the new ‘opt-out’ systems being rolled out in the UK, normothermic machine perfusion to optimise marginal grafts, a new national allocation system to maximise benefit from each organ and developments in patient ‘prehabilitation’ before listing. Current areas of research interest, such as immunosuppression withdrawal, are also summarised.     

Current controversies surrounding liver transplantation for hepatocellular carcinoma

Liver transplantation (LT) for hepatocellular carcinoma (HCC) has progressed rapidly over the last decade from a futile therapy to the first choice therapy for suitable patients. Excellent outcomes of LT for HCC can be largely attributed to the use of the Milan Criteria, which have restricted LT to patients with early stage tumors. These criteria may be conservative, and it is likely that a subset of patients with tumors beyond these criteria can have acceptable outcomes. However, there is currently insufficient data to accept more liberal criteria as a standard of care, and a higher quality evidence base must be achieved to prevent poor utilization of valuable donor liver resources. In the future, it is probable that more sophisticated selection criteria will emerge incorporating aspects of tumor biology beyond tumor size and number. Dropout from the waiting list due to tumor progression remains a clinical challenge particularly in regions with prolonged waiting times. Priority allocation using HCC MELD points is a practical and transparent solution that has successfully reduced waitlist dropout for HCC patients. Further refinements of the HCC MELD point system are required to ensure equity of access to LT for non‐HCC patients and prioritization of HCC patients with the highest risk of dropout. Improving the evidence base for pre‐LT locoregional therapy to prevent waitlist dropout is an urgent and difficult challenge for the LT community. In the interim transplant clinicians must restrict the use of these therapies to those patients who are most likely to benefit from them.     

Outcomes in partial liver transplantation: deceased donor split-liver vs. live donor liver transplantation

BackgroundOrgan shortage has resulted in greater emphasis on partial liver transplantation (PLT) as an alternative to whole-organ liver transplantation.MethodsThis study was conducted to assess outcomes in PLT and to compare outcomes of deceased donor split-liver transplantation (DD-SLT) and live donor liver transplantation (LDLT) in adults transplanted in the USA using data reported to the United Network for Organ Sharing in the era of Model for End-stage Liver Disease (MELD) scores.ResultsBetween 2002 and 2009, 2272 PLTs were performed in the USA; these represented 5.3% of all liver transplants carried out in the country and included 557 (24.5%) DD-SLT and 1715 LDLT (75.5%) procedures. The most significant differences between the DD-SLT and LDLT groups related to mean MELD scores, which were lower in LDLT recipients (14.5 vs. 20.9; P < 0.001), mean recipient age, which was lower in the LDLT group (50.7 years vs. 52.8 years; P < 0.001), and mean donor age, which was lower in the DD-SLT group (23.0 years vs. 37.3 years; P < 0.001). Allograft survival was comparable between the two groups (P= 0.438), but patient survival after LDLT was better (P= 0.04). In Cox regression analysis, LDLT was associated with better allograft (hazards ratio [HR]= 0.7, 95% confidence interval [CI] 0.630–0.791; P < 0.0001) and patient (HR = 0.6, 95% CI 0.558–0.644; P < 0.0001) survival than DD-SLT.ConclusionsPartial liver transplantation represents a potentially underutilized resource in the USA. Despite the differences in donor and recipient characteristics, LDLT is associated with better allograft and patient survival than DD-SLT. A different allocation system for DD-SLT allografts that takes into consideration cold ischaemia time and recipient MELD score should be considered.     

Liver transplantation in alcoholic liver disease current status and controversies

Alcoholic cirrhosis remains the second most common indication for liver transplantation.A comprehensive medical and psychosocial evaluation is needed when making a decision to place such patients on the transplant list.Most transplant centers worldwide need a minimum of 6 mo of alcohol abstinence for listing these patients.Patients with alcohol dependence are at high risk for relapse to alcohol use after transplantation(recidivism).These patients need to be identified and require alcohol rehabilitation treatment before transplantation.Recidivism to the level of harmful drinking is reported in about 15%-20%cases.Although,recurrent cirrhosis and graft loss from recidivism is rare,occurring in less than 5%of all alcoholic cirrhosis-related transplants,harmful drinking in the post-transplant pe-riod does impact the long-term outcome.The development of metabolic syndrome with cardiovascular events and de novo malignancy are important contributors to non liver-related mortality amongst transplants for alcoholic liver disease.Surveillance protocols for earlier detection of de novo malignancy are needed to improve the long-term outcome.The need for a minimum of 6 mo of abstinence before listing makes transplant a nonviable option for patients with severe alcoholic hepatitis who do not respond to corticosteroids.Emerging data from retrospective and prospective studies has challenged the 6 mo rule,and beneficial effects of liver transplantation have been reported in select patients with a first episode of severe alcoholic hepatitis who are unresponsive to steroids.     

儿童肝移植的现状和未来

儿童肝移植已经成为儿童终末期肝病的标准治疗方法。发展儿童肝移植意义重大。本文从适应证、生存率、手术方式、技术性并发症、免疫抑制治疗、远期生存状况和受体危险度分层等方面对目前儿童肝移植的发展水平进行初步概述,并对未来发展作初步展望。     

Domino liver transplantation

Orthotopic liver transplantation is today an established treatment for end stage liver diseases. However, the ongoing shortage of suitable livers together with progressively longer waiting lists prevents many patients from being transplanted, and many patients die while being on the waiting list. Using livers from living donors is one way to increase the supply of liver grafts. Another group of potential living liver donors are some selected liver recipients, whose native explanted liver in turn can be considered for transplantation into another patient. This unorthodox procedure have been named domino liver transplantation (DLT). The domino approach can be considered in patients with some genetic or biochemical disorders that today are treated by liver transplantation. The underlying rationale is that such livers ultimately cause severe systemic disease but are otherwise normal. In this review we present the current world status of DLT as well as updated results from the Domino Liver World Transplant Register (DLTR) and our own experience at the Karolinska University Hospital Huddinge with the DLT procedure.     

Live donors in liver transplantation

Living donor liver transplantation (LDLT) has been controversial since its inception. Begun in response to deceased donor organ shortage and waiting list mortality, LDLT was initiated in 1989 in children, grew rapidly after its first general application in adults in the United States in 1998, and has declined since 2001. There are significant risks to the living donor, including the risk of death and substantial morbidity, and 2 highly publicized donor deaths are thought to have contributed to decreased enthusiasm for LDLT. Significant improvements in outcomes have been seen over recent years, and data, including from the National Institutes of Health-funded Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL), have established a survival benefit from pursuing LDLT. Despite this, LDLT still composes less than 5% of adult liver transplants, significantly less than in kidney transplantation where living donors compose approximately 40% of all transplantations performed. The ethics, optimal utility, and application of LDLT remain to be defined. In addition, most studies to date have focused on posttransplantation outcomes and have not included the effect of the learning curve on outcome or the potential impact of LDLT on waiting list mortality. Further growth of LDLT will depend on defining the optimal recipient and donor characteristics for this procedure as well as broader acceptance and experience in the public and in transplant centers.     

Current developments in pediatric liver transplantation

In 1953, the pioneer of human orthotopic liver transplantation(LT), Thomas E Starzl, was the first to attempt an orthotopic liver transplant into a 3 years old patient suffering from biliary atresia. Thus, the first LT in humans was attempted in a disease, which, up until today, remains the main indication for pediatric LT(p LT). During the last sixty years, refinements in diagnostics and surgical technique, the introduction of new immunosuppressive medications and improvements in perioperative pediatric care have established LT as routine procedure for childhood acute and chronic liver failure as well as inherited liver diseases. In contrast to adult recipients, p LT differs greatly in indications for LT, allocation practice, surgical technique, immunosuppression and postoperative life-long aftercare. Many aspects are focus of ongoing preclinical and clinical research. The present review gives an overview of current developments and the clinical outcome of p LT, with a focus on alternatives to full-size deceased-donor organ transplantation.     

Case report: Donor acquired visceral leishmaniasis following liver transplantation

Patients who undergo solid organ transplantation are at risk of opportunistic infection associated with immunosuppression. We report a case of confirmed donor derived visceral leishmaniasis (VL), in a patient following liver transplantation causing fever and pancytopenia. The diagnosis was confirmed by bone marrow biopsy, with confirmed positive donor serology, with no other route of transmission. To our knowledge, this is the first case report in the United Kingdom and Europe, of confirmed organ donor transmission of VL. This case report highlights an important consideration of donor derived infections, in the context of solid organ transplantation.     

Pregnancy and liver transplantation

Since the first pregnancy in a transplant recipient in 1958, pregnancy in recipients of solid organ transplants has become increasingly common. Although previously considered a hazardous event, data collected over the last 50 years demonstrate that despite an increased risk of maternal and fetal complications, pregnancy in transplant recipients can have a successful outcome. As of 2006, there were over 3000 female liver transplant recipients of childbearing age in the USA. Two hundred and two pregnancies and 205 outcomes were reported in 121 liver transplant recipients in the National Transplantation Pregnancy Registry. Children born to female liver recipients have a greater risk of prematurity and low birth weight than the general population, but no malformation patterns have been observed. Mothers are more likely to experience pregnancy‐induced hypertension, pre‐eclampsia and caesarian section, but overall mortality is not worse. Rates of acute rejection and graft loss are similar to nonpregnant liver recipients. The optimal timing of conception post‐transplant is controversial, but current recommendations suggest waiting for at least 1 year after transplantation. Choice of contraception is also debatable, although barrier methods have traditionally been preferred. Many medications used for post‐transplant immunosuppression have potential effects during pregnancy and breast‐feeding. The risks and benefits of each medication should be reviewed with patients contemplating pregnancy, and regimens should be tailored accordingly.     

肝移植在中国的发展现状

作为治疗各种终末期肝病唯一有效的方法,肝移植近年在国内发展迅速。叙述了肝移植在国内的最新发展成果,包括肝癌肝移植受者选择标准——杭州标准的确立;挽救性肝移植及降期治疗在肝癌肝移植中的最新应用;肝移植联合人工肝技术治疗急性重症肝衰竭的进展;活体肝移植技术创新和心脏死亡器官捐献移植在中国的突破性发展。面临器官短缺,应建立符合中国国情的科学规范的器官捐献体系,在造福于广大人民的同时也将进一步提升我国器官移植学界在国际上的声誉。     

The need for venovenous bypass in liver transplantation

Since introduction of the conventional liver transplantation (CLTx) by Starzl, which was based on the resection of recipient inferior vena cava (IVC) along the liver, the procedure has undergone several refinements. Successful use of venovenous bypass (VVB) was first introduced by Shaw et al., although in recent decades there has been controversy regarding the routine use of VVB during CLTx. With development of piggyback liver transplantation (PLTx), the use of caval clamping and VVB is avoided, leading to fewer complications related to VVB. However, some authors still advocate VVB in PLTx. The great diversity among centers in their use of VVB during CLTx, or even along the PLTx technique, has led to confusion regarding the indication setting for VVB. For this reason, we present an overview of the use of VVB in CLTx, the target of patients for whom VVB could be beneficial, and the needs assessment of VVB for patients undergoing PLTx. Recent studies have shown that with the advancement of surgical skills, refinement of surgical techniques, and improvements in anesthesiology, there are only limited indications for doing CLTx with VVB routinely. PLTx with preservation of IVC can be performed in almost all primary transplants and in the majority of re-transplantations without the need for VVB. Nevertheless, in a few selective cases with severe intra-operative hemodynamic instability, or with a failed test of transient IVC occlusion, the application of VVB is still justifiable. These indications should be judged intra-operatively and the decision is based on each center's preference.     

Kidney transplantation after liver transplantation

Kidney transplantation after liver transplanta-tion (KALT) offers longer survival and a better quality of life to liver transplantation recipients who develop chronic renal failure. This article aimed to discuss the efifcacy and safety of KALT compared with other treatments. The medical records of 5 patients who had undergone KALT were retrospectively studied, together with a literature review of studies. Three of them developed chronic renal failure after liver transplanta-tion because of calcineurin inhibitor (CNI)-induced neph-rotoxicity, while the others had lupus nephritis or non-CNI drug-induced nephrotoxicity. No mortality was observed in the 5 patients. Three KALT cases showed good prognoses, maintaining a normal serum creatinine level during entire follow-up period. Chronic rejection occurred in the other two patients, and a kidney graft was removed from one of them. Our data suggested that KALT is a good alternative to dialysis for liver transplantation recipients. The cases also indicate that KALT can be performed with good long-term survival.     

Technical advances in living-related liver transplantation

Since it was first reported in 1989, living-related liver transplantation (LRLT) has developed, and up to April, 1998, over 800 LRLTs had been performed worldwide. The past few years have seen considerable technical advances in LRLT, including selective vascular occlusion techniques for donor hepatectomy, arterial reconstruction using microscopy, and the introduction of intraoperative ultrasound and graft volume estimation, using the concept of standard liver volume, which have enabled LRLT to be extended to adult recipients. Successful results have led to LRLT becoming an indispensable modality to overcome the shortage of cadaveric liver grafts in Western countries. In places where transplantation of organs from brain-dead donors is rarely practiced, such as in most Asian countries, LRLT is the only means of saving patients with end-stage liver disease who otherwise would have no chance of survival. LRLT is now globally accepted as an effective liver transplantation modality.     

Living-related liver transplantation: Report of experiences at Shinshu University Hospital

In view of the relative scarcity of pediatric cadaveric donors, living-related liver transplantation has recently been accepted as an alternative approach. It is also the only method of liver transplantation available in countries where cadaveric organ procurement is prohibited. Here we describe our experience of living-related liver transplantation in 17 patients at Shinshu University Hospital. The safety of the donor operation is of paramount importance in this type of liver transplantation. In Japan, retransplantation is very difficult in the event of the liver graft becoming nonfunctional. We have therefore placed emphasis on the donor hepatectomy technique as well as on surgical procedures and postoperative care to prevent graft loss in the recipient. Fifteen of the 17 patients who received liver transplants are currently alive; and 1 died of cytomegalovirus infection, and 1 of pulmonary complications. The actuarial 1-year survival rate for our series, determined by Kaplan-Meier analysis, was 89.5%. Although living-related liver transplantation requires a complicated surgical procedure, it has achieved reasonable results for both donors and recipients. We consider that living-related liver transplantation is a useful and reasonable option for patients requiring liver transplantation.     

Living donor liver transplantation: issues regarding left liver grafts

BackgroundThe necessity of widening the indications for living donor liver transplantation (LDLT) has been emphasised. Clarification of the advantages and limitations of using a left liver graft for LDLT in adults is essential for donor safety.MethodsBetween June 1990 and November 2002, 185 patients underwent LDLT at Shinshu University Hospital, Japan. In 97 of these, the graft comprised the left liver with or without the left portion of the caudate lobe. The peri-hepatectomy profiles of the donors, significance of left liver grafts, postoperative courses of the donors and recipients, and survival of the recipients were investigated.ResultsAll the donors recovered well and returned to a normal lifestyle. None required banked-blood transfusion or repeat surgery, and postoperative liver function tests had satisfactory results. The cold ischaemic time for the graft was 127±54 minutes. The graft volumes (GVs) ranged from 230 to 625 ml, and GV/standard liver volume (SV) ratios varied from 22% to 65%, at the time of transplantation. Although 85% of the liver grafts had GV/SV ratios <50%, no patient developed immediate postoperative liver failure. Patient survival rates were 89%, 84% and 84% at 1, 3 and 5 years, respectively.DiscussionAlthough LDLT using a left liver graft imposes potential postoperative complications (a small liver is more vulnerable to injury, and recipients of small grafts are at higher risk of complications during recovery), such grafts have yielded acceptable results in adult LDLT, with minimal burden to the donors.