Excellent long-term patient and graft survival are possible with appropriate use of livers from deceased septuagenarian and octogenarian donors

Is the liver resilient to the process of ageing?

The liver's unique regenerative capacity, immunotolerant feature, and polyploidy status distinguish it as a metabolic organ unlike any other in the body. Despite aging, the liver generally exhibits fewer pathological abnormalities than other organs (such as the kidney), maintaining its functions near-normal balanced manner. Subtle changes in the liver, including reduced blood flow, detoxification alterations, pseudo-capillarization, and lipofuscin deposition, may occur with chronological age. Research indicates that carefully selected liver grafts from octogenarian donors can perform well post-transplant, emphasizing instances where age doesn't necessarily compromise liver function. Notably, a recent report suggests that the liver is a youthful organ, with hepatocytes averaging an age of only 3 years. Despite the liver's impressive regenerative capabilities and cellular reserve, a lingering question persists: how does the liver maintain its youthful characteristic amidst the chronological aging of the entire organism? The various adaptive mechanism possibly include:(a) cellular hypertrophy to maintain physiological capacity even before proliferation initiates, (b) the "ploidy conveyor" as a genetic adaptation to endure aging-related stress, (c) sustained telomere length indicative of youthfulness (d) active extracellular matrix remodelling for normal cellular functioning, (e) Mitochondria-Endoplasmic Reticulum based metabolic adaptation and (c) cellular plasticity as fitness mechanisms for healthy aging. However, it's crucial to note that aged livers may have compromised regenerative capacity and chronic liver disease is often associated with declining function due to premature hepatocyte senescence. This review delves into varied cellular adaptations sustaining liver homeostasis with chronological aging and briefly explores the role of accelerated hepatocyte aging as a precursor to chronic liver disease.

Influence of donor age on liver transplantation outcomes: A multivariate analysis and comparative study

BACKGROUND

The growing disparity between the rising demand for liver transplantation (LT) and the limited availability of donor organs has prompted a greater reliance on older liver grafts. Traditionally, utilizing livers from elderly donors has been associated with outcomes inferior to those achieved with grafts from younger donors. By accounting for additional risk factors, we hypothesize that the utilization of older liver grafts has a relatively minor impact on both patient survival and graft viability.

AIM

To evaluate the impact of donor age on LT outcomes using multivariate analysis and comparing young and elderly donor groups.

METHODS

In the period from April 2013 to December 2018, 656 adult liver transplants were performed at the University Hospital Merkur. Several multivariate Cox proportional hazards models were developed to independently assess the significance of donor age. Donor age was treated as a continuous variable. The approach involved univariate and multivariate analysis, including variable selection and assessment of interactions and transformations. Additionally, to exemplify the similarity of using young and old donor liver grafts, the group of 87 recipients of elderly donor liver grafts (≥ 75 years) was compared to a group of 124 recipients of young liver grafts (≤ 45 years) from the dataset. Survival rates of the two groups were estimated using the Kaplan-Meier method and the log-rank test was used to test the differences between groups.

RESULTS

Using multivariate Cox analysis, we found no statistical significance in the role of donor age within the constructed models. Even when retained during the entire model development, the donor age's impact on survival remained insignificant and transformations and interactions yielded no substantial effects on survival. Consistent insignificance and low coefficient values suggest that donor age does not impact patient survival in our dataset. Notably, there was no statistical evidence that the five developed models did not adhere to the proportional hazards assumption. When comparing donor age groups, transplantation using elderly grafts showed similar early graft function, similar graft (P = 0.92), and patient survival rates (P = 0.86), and no significant difference in the incidence of postoperative complications.

CONCLUSION

Our center's experience indicates that donor age does not play a significant role in patient survival, with elderly livers performing comparably to younger grafts when accounting for other risk factors.

Post-transplant biliary complications using liver grafts from deceased donors older than 70 years: Retrospective case-control study

BACKGROUND

The shortage of liver grafts and subsequent waitlist mortality led us to expand the donor pool using liver grafts from older donors.

AIM

To determine the incidence, outcomes, and risk factors for biliary complications (BC) in liver transplantation (LT) using liver grafts from donors aged > 70 years.

METHODS

Between January 1994 and December 31, 2019, 297 LTs were performed using donors older than 70 years. After excluding 47 LT for several reasons, we divided 250 LTs into two groups, namely post-LT BC (n = 21) and without BC (n = 229). This retrospective case-control study compared both groups.

RESULTS

Choledocho-choledochostomy without T-tube was the most frequent technique (76.2% in the BC group vs 92.6% in the non-BC group). Twenty-one patients (8.4%) developed BC (13 anastomotic strictures, 7 biliary leakages, and 1 non-anastomotic biliary stricture). Nine patients underwent percutaneous balloon dilation and nine required a Roux-en-Y hepaticojejunostomy because of dilation failure. The incidence of post-LT complications (graft dysfunction, rejection, renal failure, and non-BC reoperations) was similar in both groups. There were no significant differences in the patient and graft survival between the groups. Moreover, only three deaths were attributed to BC. While female donors were protective factors for BC, donor cardiac arrest was a risk factor.

CONCLUSION

The incidence of BC was relatively low on using liver grafts > 70 years. It could be managed in most cases by percutaneous dilation or Roux-en-Y hepaticojejunostomy, without significant differences in the patient or graft survival between the groups.

Expanding Liver Transplant Opportunities in Older Patients With Nonconventional Grafts

INTRODUCTION

Broader use of donation after circulatory death (DCD) and nonconventional grafts for liver transplant helps reduce disparities in organ availability. Limited data, however, exists on outcomes specific to nonconventional graft utilization in older patients. As such, this study aimed to investigate outcomes specific to conventional and nonconventional graft utilization in recipients > 70 y of age.

METHODS

1-to-3 matching based on recipient sex, Model for End-Stage Liver Disease score, and donor type was performed on patients ≥70 and <70 y of age who underwent liver transplant alone at Mayo Clinic Arizona between 2015 and 2020. Primary outcomes were posttransplant patient and liver allograft survival for recipients greater than or less than 70 y of age. Secondary outcomes included grafts utilization patterns, hospital length of stay, need for reoperation, biliary complications and disposition at time of hospital discharge.

RESULTS

In this cohort, 36.1% of grafts came from DCD donors, 17.4% were postcross clamp offers, and 20.8% were nationally allocated. Median recipient ages were 59 and 71 y (P < 0.01). Recipients had similar Intensive care unit (P = 0.82) and hospital (P = 0.14) lengths of stay, and there were no differences in patient (P = 0.68) or graft (P = 0.38) survival. When comparing donation after brain death and DCD grafts in those >70 y, there were no differences in patient (P = 0.89) or graft (P = 0.71) survival.

CONCLUSIONS

Excellent outcomes can be achieved in older recipients, even with use of nonconventional grafts. Expanded use of nonconventional grafts can help facilitate transplant opportunities in older patients.

Impact of donor age on short-term outcomes after pediatric split liver transplantation

Background

Donor shortage is an important limitation of liver transplantation (LT). Split liver transplantation (SLT) may increase the sources of donors and reduce the problem of organ shortage. However, there are no standard criteria of the selection of SLT donor, especially regarding the donor age.

Methods

We retrospectively analyzed the clinical data of children who received initial SLT between January 2015 and December 2021. Based on the age of donors, the patients were divided into groups A (1-10 years old; n = 26), B (10-45 years old; n = 87), and C (45-55 years old; n = 27). The short-term (<1 year after SLT) outcomes of the recipients were analyzed.

Results

A total of 140 patients received SLT from 122 donors. The 1-, 3- and 12-month patient survival rates in group A were 100.0%, and the graft survival rates were 92.3%. The 1-, 3- and 12-month survival rates of patient and graft in group B were 97.7%, 96.6%, and 95.0%, respectively, and in group C were 85.2%, 85.2%, and 81.1%, respectively. The patient survival rate was significantly lower in group C than in groups A and B (p = 0.0082). There was no significant difference in graft survival between the three groups (p = 0.0545).

Conclusions

Similar results were obtained for pediatric SLT with donors <10 years old and 10-45 years old. Pediatric SLT can be performed with older donors (45-55 years) after strict donor selection and selection of appropriate recipients.

The impact of hepatitis C virus direct acting agents in liver transplant using very old donor grafts: a real-world single-center analysis

The correct timing of use of direct acting agents (DAAs) among transplanted patients remains unknown. The aim of this paperwork is to evaluate the impact of DAAs treatment in pre- or peri-operative period in liver transplantation when grafts ≥ 70 years are used. This is a retrospective analysis comparing adult liver transplant performed for HCV-related cirrhosis and/or hepatocarcinoma using a graft ≥ 70 in the period 2015-2018 (Group DAA-HCV-OLD, study group) to three different groups: (a) anti-HCV-Ab-negative patients receiving graft ≥ 70 (no-HCV-OLD), (b) anti-HCV-Ab-negative patients receiving a graft aged 18-69 years (no-HCV-YOUNG), and (c) anti-HCV-Ab-positive patients receiving a donor graft ≥ 70 in the period 2007-2011 (no-DAA-HCV-OLD). Totally, 528 liver transplants were considered: 164 in DAA-HCV-OLD, 143 in no-HCV-OLD, 120 in no-HCV-YOUNG and 101 in no-DAA-HCV-OLD Group. Graft survival rates at 1 and 3 years were 88% and 81% in DAA-HCV-OLD Group, 82% and 68% in no-DAA-HCV-OLD (p = 0.007), 89% and 84% in no-HCV-OLD (p = 0.76), and 94% and 92% in no-HCV-YOUNG (p = 0.02). No differences were observed among groups in the incidence of primary non-function, primary dysfunction, vascular or biliary complications. DAAs were able to zero HCV-related graft loss, with a 3-year graft survival > 80%. The outcomes of older graft recipients became equal irrespectively of their HCV serological status.

Safe use of livers from deceased donors older than 70 years in recipients with HCV cirrhosis treated with direct-action antivirals. Retrospective cohort study

INTRODUCTION

There is controversy regarding the use of older grafts for liver transplantation (LT) in HCV-infected patients, but the introduction of direct-acting antivirals (DAA) can radically change that debate.

METHODS

The aim of this retrospective cohort study was to evaluate outcomes of the use of liver grafts from donors older than 70 years in recipients with HCV infection who underwent pre- or post-LT treatment with DAA. We compared two groups of patients who underwent LT using livers >70 years; the groups were defined according to antiviral therapy: non-DAA therapy group (n = 62; LT between May 1996 and December 2013), and DAA therapy group (n = 31; LT between January 2014 and December 2019).

RESULTS

Thirty (96.8%) patients of DAA therapy and nine (14.5%) of non-DAA therapy (21 patients underwent complete therapy with interferon-ribavirin) achieved sustained viral response (SVR). One, 3-, and 5-year patient survival were 83.9%, 67.7%, and 56.5% in the non-DAA group vs 93.5%, 88.4%, and 88.4% in the DAA group (P = 0.04); the 1-, 3-, and 5-year graft survival were 77.4%, 62.9%, and 51.6% in the non-DAA group vs. 88.6%, 83.7%, and 83.7% in the DAA group (P = 0.03). Multivariate analysis demonstrated donor female sex and DAA therapy as protective factors of graft survival.

CONCLUSIONS

Pre- or post-LT therapy with DAA in HCV-infected patients has achieved an almost overall SVR. The use of liver grafts >70 years in these patients treated with DAA was associated with significantly higher 5-year patient and graft survival in DAA group compared to non-DAA group. Thus, the introduction of DAA therapy has allowed the safe use of livers >70 years in HCV-positive recipients.

Use of Elderly Donors in Liver Transplantation: A Paired-match Analysis at a Single Center

OBJECTIVE

To evaluate the use of elderly donors in liver transplantation (LT) and identify risk factors associated with a worse outcome.

SUMMARY BACKGROUND DATA

Use of livers from very old donors could expand the donor pool but is not universally implemented.

METHODS

This is a retrospective, single-center medical record review. From January 2001 to December 2014, 1354 LTs were performed. After exclusion of donors <18 years, ABO-incompatible LT, re-LT and UNOS 1 status patients, LT recipients were stratified into 2 groups based on donor age: 18-69 (n=692) vs. ≥70 years (n=515) then matched using a propensity score approach. Two groups were finally matched (young group = 448 cases; old group = 515 cases).

RESULTS

The median (interquartile range [IQR]) follow-up was 5.0 (2.0-8.4) years. Comparing the 2 identified groups, no differences were observed regarding early retransplants (1.8 vs. 2.9; P = 0.3), HCV-related death (7.6 vs. 8.7%; P = 0.6), vascular (5.8 vs. 5.0%; P = 0.7), and biliary complications (16.5 vs. 18.6%; P = 0.4). On multivariate analysis, independent risk factors for graft loss were: HCV-positive recipient (HR = 2.1; 95% CI = 1.6-2.7; P < 0.001), donor age (HR = 1.0; 95% CI = 1.0-1.0; P < 0.001), cold ischemia time (HR = 1.0; 95% CI = 1.0-1.0; P = 0.042), and donor history of diabetes mellitus (HR = 1.48; 95% CI = 1.03-2.13; P = 0.036).

CONCLUSIONS

Use of elderly donors is not associated per se with an increased risk of vascular and biliary complications. In the presence of cold ischemia time and diabetes mellitus, appropriate donor-to-recipient matching is warranted.

Grafts from selected deceased donors over 80 years old can safely expand the number of liver transplants: A systematic review and meta-analysis

AIM

The aim of this systematic review and meta-analysis was to present the outcome of deceased adult liver transplantation from octogenarian (≥80 years old) donors compared to younger grafts.

METHODS

A systematic search was performed on six databases to identify all available original papers that report the outcome of adult recipients who underwent liver transplantation from a deceased octogenarian donor.

RESULTS

Overall, 39,034 liver transplantations from 12 studies were reported with 789 (2.02%) cases receiving grafts from octogenarian donors. Eight studies were included in the meta-analysis. There was no difference regarding the one, three, and five-year graft and patient survival between the recipients of livers <80 years old and octogenarian grafts. There were significantly more episodes of biliary complications in the recipients of octogenarian grafts (34/459; 7.4%) in comparison to the recipients of livers <80 years old (372/37074; 1.0%) (OR 0.53; 95% CI = 0.35-0.81; P 0.004; I² = 0%). The incidence of primary non-function, vascular complications and re-transplantation did not differ between groups.

CONCLUSIONS

The short- and medium-term graft and patient survival of octogenarian liver transplantation is not inferior compared to the liver transplantation with younger grafts, however with a higher rate of biliary complications.

The dawn of liver perfusion machines

PURPOSE OF REVIEW

Despite high demand, a severe shortage of suitable allografts limits the use of liver transplantation for the treatment of end-stage liver disease. The transplant community is turning to the utilization of high-risk grafts to fill the void. This review summarizes the reemergence of ex-vivo machine perfusion for liver graft preservation, including results of recent clinical trials and its specific role for reconditioning DCD, steatotic and elderly grafts.

RECENT FINDINGS

Several phase-1 clinical trials demonstrate the safety and feasibility of machine perfusion for liver graft preservation. Machine perfusion has several advantages compared with static cold storage and may provide superior transplantation outcomes, particularly for marginal grafts. Ongoing multicenter trials aim to confirm the results of preclinical and pilot studies and establish the clinical utility of ex-vivo liver machine perfusion.

SUMMARY

Mounting evidence supports the benefits of machine perfusion for preservation of liver grafts. Thus, machine perfusion is a promising strategy to expand the donor pool by reconditioning and assessing viability of DCD, elderly and steatotic grafts during the preservation period. Additionally, machine perfusion will serve as a platform to facilitate graft intervention and modification to further optimize marginal grafts.

Optimizing the Use of Geriatric Livers for Transplantation in the Eurotransplant Region

Acceptance criteria for liver allografts are ever more expanding because of a persisting wait-list mortality. Older livers are therefore offered and used more frequently for transplantation. This study aims to analyze the use and longterm outcome of these transplantations. Data were included on 17,811 first liver transplantations (LTs) and information on livers that were reported for allocation but not transplanted from 2000 to 2015 in the Eurotransplant (ET) region. Graft survival was defined as the period between transplantation and date of retransplantation or date of recipient death. In the study period, 2394 (13%) transplantations were performed with livers ≥70 years old. Graft survival was 74%, 57%, and 41% at 1-, 5-, and 10-year follow-up, respectively. A history of diabetes mellitus in the donor (hazard ratio [HR], 1.3; P = 0.01) and positive hepatitis C virus antibody in the recipient (HR, 1.5; P < 0.001) are specific risk factors for transplantations with livers ≥70 years old. Although donor age is associated with a linearly increasing risk of graft loss between 25 and 80 years old, no difference in graft survival could be observed when "preferred" recipients were transplanted with a liver <70 or ≥70 years old (HR 1.1; CI 0.92-1.23, P = 0.40) or with a donor <40 or ≥70 years old (HR 1.2; CI 0.96-1.37, P = 0.13). Utilization of reported livers ≥70 years old increased from 42% in 2000-2003 to 76% in 2013-2015 without a decrease in graft survival (P = 0.45). In conclusion, an important proportion of LTs in the ET region are performed with livers ≥70 years old. The risk of donor age on graft loss increases linearly between 25 and 80 years old. Livers ≥70 years old can, however, be transplanted safely in preferred patients and are to be used more frequently to further reduce wait-list mortality.

Analyzing predictors of graft survival in patients undergoing liver transplantation with donors aged 70 years and over

AIM

To increase the number of available grafts.

METHODS

This is a single-center comparative analysis performed between April 1986 and May 2016. Two hundred and twelve liver transplantation (LT) were performed with donors ≥ 70 years old (study group). Then, we selected the first cases that were performed with donors < 70 years old immediately after the ones that were performed with donors ≥ 70 years old (control group).

RESULTS

Graft and patient survivals were similar between both groups without increasing the risk of complications, especially primary non-function, vascular complications and biliary complications. We identified 5 risk factors as independent predictors of graft survival: recipient hepatitis C virus (HCV)-positivity [hazard ratio (HR) = 2.35; 95% confidence interval (CI): 1.55-3.56; P = 0.00]; recipient age (HR = 1.04; 95%CI: 1.02-1.06; P = 0.00); donor age X model for end-stage liver disease (D-MELD) (HR = 1.00; 95%CI: 1.00-1.00; P = 0.00); donor value of serum glutamic-pyruvic transaminase (HR = 1.00; 95%CI: 1.00-1.00; P = 0.00); and donor value of serum sodium (HR = 0.96; 95%CI: 0.94-0.99; P = 0.00). After combining D-MELD and recipient age we obtained a new scoring system that we called DR-MELD (donor age X recipient age X MELD). Graft survival significantly decreased in patients with a DR-MELD score ≥ 75000, especially in HCV patients (77% vs 63% at 5 years in HCV-negative patients, P = 0.00; and 61% vs 25% at 5 years in HCV-positive patients; P = 0.00).

CONCLUSION

A DR-MELD ≥ 75000 must be avoided in order to obtain the best results in LT with donors ≥ 70 years old.

Association between donor age and risk of graft failure after liver transplantation: an analysis of the Eurotransplant database

Grafts from elderly donors are increasingly used for liver transplantation. As of yet there is no published systematic data to guide the use of specific age cutoffs the effect of elderly donors on patient outcomes must be clarified. This study analyzed the Eurotransplant database (01/01/2000-31/07/2014; N = 26 294) out of whom 8341 liver transplantations were filtered to identify for this analysis. 2162 of the grafts came from donors >60 including 203 from octogenarians ≥80 years. Primary outcome was the risk of graft failure according to donor age using a confounder adjusted Cox-Regression model with frailty terms (or random effects). The proportion of elderly grafts increased during the study period [i.e., octogenarians 0.1% (n = 1) in 2000 to 3.4% (n = 45) in 2013]. Kaplan-Meier and Cox-analyses revealed a reduced survival and a higher risk for graft failure with increasing donor age. Although the age effect was allowed to vary non-linearly, a linear association hazard ratio (HR = 1.1 for a 10 year increase in donor age) was evident. The linearity of the association suggests that there is no particular age at which the effect increases more rapidly, providing no evidence for a cutoff age. In clinical practice, the combination of high donor age with HU-transplantations, hepatitis C, high MELD-scores and long cold ischemic time should be avoided.

Orthotopic Liver Transplantation With Elderly Donors (Over 80 Years of Age): A Prospective Evaluation

BACKGROUND

Our main objective was to assess the clinical outcomes obtained in a single orthotopic liver transplant (OLT) hospital with donors ≥80 years of age compared to a control group of patients subjected to OLT during the same period of time with donors who were under 65 years of age.

METHODS

A prospective analysis was carried out on all the OLTs performed using liver grafts from donors in a state of brain death and with an age of ≥80 years (study group) between April 2007 and January 2015. The results of the study group (n = 36) were compared with those of a control group of patients less than 65 years of age receiving transplants with grafts.

RESULTS

A total of 51 potential donors ≥80 years were assessed, with a total of 36 liver transplants being carried out and their results were compared with a control group of 283 patients receiving transplants. The median follow-up time of the patients in the series was 36 months (range: 24-120 months). Graft survival at 1, 2, and 3 years was 77%, 72%, and 62%, respectively, among the patients in the study group and 79%, 73%, and 65% among the patients in the control group, and there were no statistically significant differences. Patient survival at 1, 2, and 3 years was 86%, 82%, and 75%, respectively, among the patients in the study group and 82%, 76%, and 72% among the patients in the control group, also without there being any statistically significant differences.

CONCLUSIONS

There is no age limit for liver transplant donors. The use of octogenarian donors makes it possible to increase the pool of donors while providing enough safety for the recipient.

Long-term outcome of renal transplantation from octogenarian donors: A multicenter controlled study

To assess whether biopsy-guided selection of kidneys from very old brain-dead donors enables more successful transplantations, the authors of this multicenter, observational study compared graft survival between 37 recipients of 1 or 2 histologically evaluated kidneys from donors older than 80 years and 198 reference-recipients of non-histologically evaluated single grafts from donors aged 60 years and younger (transplantation period: 2006-2013 at 3 Italian centers). During a median (interquartile range) of 25 (13-42) months, 2 recipients (5.4%) and 10 reference-recipients (5.1%) required dialysis (crude and donor age- and sex-adjusted hazard ratio [95% confidence interval] 1.55 [0.34-7.12], P = .576 and 1.41 [0.10-19.54], P = .798, respectively). Shared frailty analyses confirmed similar outcomes in a 1:2 propensity score study comparing recipients with 74 reference-recipients matched by center, year, donor, and recipient sex and age. Serum creatinine was similar across groups during 84-month follow-up. Recipients had remarkably shorter waiting times than did reference-recipients and matched reference-recipients (7.5 [4.0-19.5] vs 36 [19-56] and 40 [24-56] months, respectively, P < .0001 for both comparisons). Mean (± SD) kidney donor risk index was 2.57 ± 0.32 in recipients vs 1.09 ± 0.24 and 1.14 ± 0.24 in reference-recipients and matched reference-recipients (P < .0001 for both comparisons). Adverse events were similar across groups. Biopsy-guided allocation of kidneys from octogenarian donors permits further expansion of the donor organ pool and faster access to a kidney transplant, without increasing the risk of premature graft failure.

Systematic review and meta-analysis of liver transplantation using grafts from deceased donors aged over 70 years

INTRODUCTION

Due to the current organ shortage, nearly 20% of patients die waiting for a liver transplant (LT). The average donor age is on the rise, and grafts from elderly donors are offered as extended criteria grafts.

METHODS

This is a meta-analysis comparing the outcome differences of adult patients undergoing LT using grafts from <70-year-old donors vs >70-year-old donors. The primary end-points were graft and patient survival. Secondary outcomes were biliary and vascular complications as well as graft function. The odds ratio (OR) is a summary statistic with the corresponding 95% confidence interval; P < .05 was considered to be statistically significant.

RESULTS

Eight nonrandomized comparative studies with 4376 LT recipients were included. About 79.9% and 20.1% of the grafts were from <70-year-old and >70-year-old donors, respectively. Graft survival at 1 year was similar between the two groups (P = .11), but there was better 3-year and 5-year graft survival in the >70-year-old group (P = .006 and P < .0001, respectively). Patient survival was also similar between the groups at 1 year (P = .54), but with better survival at 3-year and 5-year follow-ups (P = .007 and P < .0001, respectively) in the >70-year-old group. There were no statistically significant differences in the incidence of biliary, vascular, and graft functional-related complications.

CONCLUSION

Liver grafts from selected >70-year-old donors do not pose added organ-specific risks and thus have comparable transplantation outcomes.

Hypothermic machine perfusion with metformin-University of Wisconsin solution for ex vivo preservation of standard and marginal liver grafts in a rat model

AIM

To compare the effect of University of Wisconsin (UW) solution with or without metformin, an AMP-activated protein kinase (AMPK) activator, for preserving standard and marginal liver grafts of young and aged rats ex vivo by hypothermic machine perfusion (HMP).

METHODS

Eighteen young (4 mo old) and 18 aged (17 mo old) healthy male SD rats were selected and randomly divided into three groups: control group, UW solution perfusion group (UWP), and UW solution with metformin perfusion group (MUWP). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), interleukin-18 (IL-18), and tumor necrosis factor-alpha (TNF-α) in the perfused liquid were tested. The expression levels of AMPK and endothelial nitric oxide synthase (eNOS) in liver sinusoidal endothelial cells were also examined. Additionally, microscopic evaluation of the harvested perfused liver tissue samples was done.

RESULTS

AST, ALT, LDH, IL-18 and TNF-α levels in the young and aged liver-perfused liquid were, respectively, significantly lower in the MUWP group than in the UWP group (P < 0.05), but no significant differences were found between the young and aged MUWP groups. Metformin increased the expression of AMPK and eNOS protein levels, and promoted the extracellular release of nitric oxide through activation of the AMPK-eNOS mediated pathway. Histological examination revealed that in the MUWP group, the extent of liver cells and tissue damage was significantly reduced compared with the UWP group.

CONCLUSION

The addition of metformin to the UW preservative solution for ex vivo HMP can reduce rat liver injury during cold ischemia, with significant protective effects on livers, especially of aged rats.

Actual Risk of Using Very Aged Donors for Unselected Liver Transplant Candidates: A European Single-center Experience in the MELD Era

OBJECTIVE

To evaluate the whole experience of liver transplantation (LT) with donors ≥70 years in a single center not applying specific donor/recipient matching criteria.

BACKGROUND

LT with very old donors has historically been associated with poorer outcomes. With the increasing average donor age and the advent of Model for End-stage Liver Diseases (MELD) score-based allocation criteria, an optimal donor/recipient matching is often unsuitable.

METHODS

Outcomes of all types of LTs were compared according to 4 study groups: patients transplanted between 1998 and 2003 with donors <70 (group 1, n = 396) or ≥70 years (group 2, n = 88); patients transplanted between 2004 and 2010 with donors <70 (group 3, n = 409), or ≥70 years (group 4, n = 190). From 2003, graft histology was routinely available before cross-clamping, and MELD-driven allocation was adopted.

RESULTS

Groups 1 and 2 were similar for main donor and recipient variables, and surgical details. Group 4 had shorter donor ICU stay, lower rate of moderate-to-severe graft macrosteatosis (2.3% vs 8%), and higher recipient MELD score (22 vs 19) versus group 3. After 2003, median donor age, recipient age, and MELD score significantly increased, whereas moderate-to-severe macrosteatosis and ischemia time decreased. Five-year graft survival was 63.6% in group 1 versus 59.1% in group 2 (P = 0.252) and 70.9% in group 3 versus 67.6% in group 4 (P = 0.129). Transplants performed between 1998 and 2003, recipient HCV infection, balance of risk score >18, and pre-LT renal replacement treatments were independently associated with worse graft survival.

CONCLUSIONS

Even without specific donor/recipient matching criteria, the outcomes of LT with donors ≥70 and <70 years are comparable with appropriate donor management.

Octogenarian donors in liver transplantation grant an equivalent perioperative course to ideal young donors

BACKGROUND

Use of grafts from very old donors for liver transplantation is controversial.

AIM

To compare the perioperative course of patients receiving liver grafts from young ideal vs octogenarian donors.

METHODS

Analysis of the perioperative course of patients receiving liver grafts from young, ideal (18-39 years) vs octogenarian (≥80years) deceased donors between 2001 and 2014.

RESULTS

346 patients were studied: 179 (51.7%) received grafts aged 18-39 years whereas 167 (48.3%) received a graft from a donor aged ≥80years. Intra-operative cardiovascular (p=0.2), coagulopathy (p=0.5) and respiratory (p=1.0) complications and incidence of reperfusion syndrome (p=0.3) were similar. Patients receiving a young graft required more fresh frozen plasma units (p≤0.03) but did not differ for the need of packed red cells (p=0.2) and platelet (p=0.3) transfusions. Median ICU stay was identical (p=0.4). Patients receiving octogenarian vs young grafts did not differ in terms of death or re-transplant (p=1.0) during the ICU stay. Similar cardiovascular, respiratory, renal, infectious and neurological postoperative complication rates were observed in the two groups.

CONCLUSIONS

Octogenarian donors in liver transplantation grant an equivalent perioperative course to ideal young donors.

Liver Transplantation With Older Donors: A Comparison With Younger Donors in a Context of Organ Shortage

BACKGROUND

Older liver grafts have been considered in the past decade due to organ shortage. The aim was to compare outcomes after liver transplantation with either younger or older donors.

METHODS

Patients transplanted in our center between 2004 and 2014 with younger donors (younger than 60 years; n = 253) were compared with older donors (older than 75 years; n = 157). Multiorgan transplantations, split grafts, or non-heart-beating donors were not included.

RESULTS

Donors in the older group were mostly women deceased from stroke, and only 3 patients had experienced cardiac arrest. Liver tests were significantly better in the older group than in the younger group. There was no difference regarding cold ischemia time, model for end-stage liver disease score, and steatosis. There was no significant difference regarding primary nonfunction and dysfunction, hepatic artery and biliary complications, and retransplantation rates. Graft survival was not different (65% and 64% in the older and younger groups, P = 0.692). Within the older group, hepatitis C infection, retransplantation, and emergency transplantation were associated with poor graft survival.

CONCLUSIONS

Provided normal liver tests and the absence of cardiac arrest in donors, older liver grafts (>75 years) may be safely attributed to non-hepatitis C-infected recipients in the setting of a first and nonurgent transplantation.

Octogenarian liver grafts: Is their use for transplant currently justified?

AIM

To analyse the impact of octogenarian donors in liver transplantation.

METHODS

We present a retrospective single-center study, performed between November 1996 and March 2015, that comprises a sample of 153 liver transplants. Recipients were divided into two groups according to liver donor age: recipients of donors ≤ 65 years (group A; n = 102), and recipients of donors ≥ 80 years (group B; n = 51). A comparative analysis between the groups was performed. Quantitative variables were expressed as mean values and SD, and qualitative variables as percentages. Differences in properties between qualitative variables were assessed by χ² test. Comparison of quantitative variables was made by t-test. Graft and patient survivals were estimated using the Kaplan-Meier method.

RESULTS

One, 3 and 5-year overall patient survival was 87.3%, 84% and 75.2%, respectively, in recipients of younger grafts vs 88.2%, 84.1% and 66.4%, respectively, in recipients of octogenarian grafts (P = 0.748). One, 3 and 5-year overall graft survival was 84.3%, 83.1% and 74.2%, respectively, in recipients of younger grafts vs 84.3%, 79.4% and 64.2%, respectively, in recipients of octogenarian grafts (P = 0.524). After excluding the patients with hepatitis C virus cirrhosis (16 in group A and 10 in group B), the 1, 3 and 5-year patient (P = 0.657) and graft (P = 0.419) survivals were practically the same in both groups. Multivariate Cox regression analysis demonstrated that overall patient survival was adversely affected by cerebrovascular donor death, hepatocarcinoma, and recipient preoperative bilirubin, and overall graft survival was adversely influenced by cerebrovascular donor death, and recipient preoperative bilirubin.

CONCLUSION

The standard criteria for utilization of octogenarian liver grafts are: normal gross appearance and consistency, normal or almost normal liver tests, hemodynamic stability with use of < 10 μg/kg per minute of vasopressors before procurement, intensive care unit stay < 3 d, CIT < 9 h, absence of atherosclerosis in the hepatic and gastroduodenal arteries, and no relevant histological alterations in the pre-transplant biopsy, such as fibrosis, hepatitis, cholestasis or macrosteatosis > 30%.

The use of old donors in liver transplantation

The process of ageing has an impact on the entire human body including the organ systems. In transplantation, professionals are daily faced with risk assessment of suitable donor offers , whether to accept a liver graft for a specific recipient. In this context, livers from elderly donors are more frequently accepted for transplantation, to increase the donor pool and compensate the high waiting list mortality. In the current practice it is not unusual to accept 60-year old donor livers for transplantation, as the donor demographics have significantly changed over the years. However, controversy exists regarding the use of livers from donors above 70 or 80 years, particular in combination with other risk factors, e.g. liver steatosis, warm ischaemia or long cold storage. This review focuses first on the impact of ageing on liver morphology and function. Second, we will highlight outcome after transplantation from elderly donors. Finally, we describe further risk factors and donor-recipient selection under the scope of old donor organs and include our institutional experience and policy.

Donor Age Still Matters in Liver Transplant: Results From the United Network for Organ Sharing-Scientific Registry of Transplant Recipients Database

OBJECTIVES

Individuals older than 60 years represent a large proportion of the organs available for orthotopic liver transplant. However, the use of organs from older donors remains controversial. We hypothesized that the use of older donors would not affect patient and graft survival due to significant improvements in donor-recipient management.

MATERIALS AND METHODS

We conducted a retrospective cohort analysis using the United Network for Organ Sharing database from February 2002 through December 2012, including non-HCV-infected adults (18 and older) who underwent primary orthotopic liver transplant. We compared patient and graft survival between 4 cohorts based on donor's age (< 60, 60-69, 70-79, and 80+ years) using the Kaplan-Meier estimator. Cox proportional hazards models were constructed to adjust for recipient and donor characteristics to estimate the risk associated with organs from older donors.

RESULTS

We identified 35 788 liver transplant recipients. Unadjusted analyses indicated that both patient and graft survival were similar among recipients of donors older than 60 years but significantly inferior compared with those recipients who received a liver from a donor younger than 60 years. Multivariate regression revealed that all 3 categories of donor age > 60 years old were significantly associated with worse patient and graft survival. Model for End-Stage Liver Disease score was not an effective modifier of the association between donor age and survival.

CONCLUSIONS

The use of liver grafts from elderly donors has a negative impact on both patient and graft survival. Recipient's Model for End-Stage Liver Disease score did not change survival based on donor age.

Results of the TOP Study: Prospectively Randomized Multicenter Trial of an Ex Vivo Tacrolimus Rinse Before Transplantation in EDC Livers

Background

Organ shortage results in the transplantation of extended donor criteria (EDC) livers which is associated with increased ischemia-reperfusion injury (IRI). Experimental studies indicate that an organ rinse with the calcineurin inhibitor tacrolimus before implantation protects against IRI. The tacrolimus organ perfusion study was initiated to examine the effects of ex vivo tacrolimus perfusion on IRI in transplantation of EDC livers.

Methods

A prospective randomized multicenter trial comparing ex vivo perfusion of marginal liver grafts (≥2 EDC according to Eurotransplant manual) with tacrolimus (20 ng/mL) or histidine-tryptophane-ketoglutarate solution (control) was carried out at 5 German liver transplant centers (Munich Ludwig-Maximilians University, Berlin, Heidelberg, Mainz, Regensburg) between October 2011 and July 2013. Primary endpoint was the maximum alanine transaminase (ALT) level within 48 hours after transplantation. Secondary endpoints were aspartate transaminase (AST), prothrombine ratio, and graft-patient survival within an observation period of 1 week. After an interim analysis, the study was terminated by the scientific committee after the treatment of 24 patients (tacrolimus n = 11, Control n = 13).

Results

Tacrolimus rinse did not reduce postoperative ALT peaks compared with control (P = 0.207; tacrolimus: median, 812; range, 362-3403 vs control: median, 652; range, 147-2034). Moreover, ALT (P = 0.100), prothrombine ratio (P = 0.553), and bilirubin (P = 0.815) did not differ between the groups. AST was higher in patients treated with tacrolimus (P = 0.011). Survival was comparable in both groups (P > 0.05).

Conclusions

Contrary to experimental findings, tacrolimus rinse failed to improve the primary endpoint of the study (ALT). Because 1 secondary endpoint (AST) was even higher in the intervention group, the study was terminated prematurely. Thus, tacrolimus rinse cannot be recommended in transplantation of EDC livers.

Liver transplant recipients and prioritization of anti-HCV therapy: an Italian cohort analysis

BACKGROUND AND AIMS

In patients with hepatitis C virus (HCV), recurrence of infection after liver transplant (LT) is universal and associated with worst survival. We present the results of an Italian cohort to compare the 3-year outcome of HCV-Ab-positive and HCV-Ab-negative LT recipients and to assess the potential interaction between HCV-Ab sero-status and other risk factors for LT failure.

METHODS

The study is a multicentre cohort including a sample of liver transplant centres. Participant's information was collected at the local level. The best functional form of variables was decided according to the objective methods based on information theory. Association between transplant failure and potential risk factors was assessed in univariate and multivariate Poisson regression model with random intercept.

RESULTS

Between June 2007 and May 2009, 1164 LT recipients were enrolled in 16 Italian transplant centres, of them 275 (23.63%) experienced LT failure. Incidence rates of LT failure was 0.32 and 0.23 per 1000 person-days in HCV-Ab-positive and HCV-Ab-negative recipients respectively (P = 0.003). Inferential models according to Akaike information criterion indicated that donor-recipient age difference and donor-recipient sex matching were more informative to predict LT failure than the age and the sex as separate variables. Multivariate analysis provided evidence that HCV-Ab sero-status, time after LT, donor-recipient age difference, donor-recipient sex matching and recipient's MELD score were significantly associated with LT failure. Moreover, the effect of HCV-Ab sero-status on LT failure was modified by the simultaneous action of time after LT and donor-recipient age difference. No interaction was found between recipient's HCV-Ab sero-status and either recipient's MELD or donor-recipient sex matching.

CONCLUSION

In view of the imminent introduction of new anti-HCV therapies, our study provides information to assess which LT recipients should be prioritized for receiving these highly effective, but expensive, new treatments. This is particularly relevant for those clinical settings where healthcare prioritization is endorsed by national authorities.