Asian Liver Transplant Network Clinical Guidelines on Immunosuppression in Liver Transplantation

Mesenchymal stem cell therapy for liver transplantation: clinical progress and immunomodulatory properties

Although liver transplantation (LT) is an effective strategy for end-stage liver diseases, the shortage of donor organs and the immune rejection hinder its widespread implementation in clinical practice. Mesenchymal stem cells (MSCs) transplantation offers a promising approach for patients undergoing liver transplantation due to their immune regulatory capabilities, hepatic protection properties, and multidirectional differentiation potential. In this review, we summarize the potential applications of MSCs transplantation in various LT scenarios. MSCs transplantation has demonstrated effectiveness in alleviating hepatic ischemia-reperfusion injury, enhancing the viability of liver grafts, preventing acute graft-versus-host disease, and promoting liver regeneration in split LT therapy. We also discuss the clinical progress, and explore the immunomodulatory functions of MSCs in response to both adaptive and innate immune responses. Furthermore, we emphasize the interactions between MSCs and different immune cells, including T cells, B cells, plasma cells, natural killer cells, dendritic cells, Kupffer cells, and neutrophils, to provide new insights into the immunomodulatory properties of MSCs in adoptive cell therapy.

Downstaging of Hepatocellular Carcinoma Before Liver Transplantation: Current Advances in Selection Criteria and Therapeutic Options

Liver transplantation (LT) is an ideal therapeutic option for selected patients with hepatocellular carcinoma (HCC). The selection criteria of HCC for LT have evolved in recent decades. Downstaging therapy is a promising strategy for patients with tumor burden beyond transplant criteria to increase the chance of receiving LT and improve posttransplant survival. Downstaging therapy is also a selection tool that refines the conventional selection criteria based on tumor morphology. Recently, the success of systemic treatment, including immune checkpoint inhibitors, antiangiogenic tyrosine kinase inhibitors, and VEGF inhibitors, in advanced HCC has prompted the discussion regarding the role of systemic therapies for HCC downstaging before transplantation. In this review, we aimed to summarize the current advances in selection criteria and therapeutic options of downstaging therapy for HCC before LT.

Immunosuppression in liver transplant oncology: position paper of the Italian Board of Experts in Liver Transplantation (I-BELT)

Liver transplant oncology (TO) represents an area of increasing clinical and scientific interest including a heterogeneous group of clinical-pathological settings. Immunosuppressive management after LT is a key factor relevantly impacting result. However, disease-related guidance is still lacking, and many open questions remain in the field. Based on such a substantial lack of solid evidences, the Italian Board of Experts in Liver Transplantation (I-BELT) (a working group including representatives of all national transplant centers), unprecedently promoted a methodologically sound consensus conference on the topic, based on the GRADE approach. The group final recommendations are herein presented and commented. The 18 PICOs and Statements and their levels of evidence and grades of recommendation are reported and grouped into seven areas: (1) risk stratification by histopathological and bio-molecular parameters and role of mTORi post-LT; (2) steroids and HCC recurrence; (3) management of immunosuppression when HCC recurs after LT; (4) mTORi monotherapy; (5) machine perfusion and HCC recurrence after LT; (6) physiopathology of tumor-infiltrating lymphocytes and immunosuppression, the role of inflammation; (7) immunotherapy in liver transplanted patients. The interest in mammalian targets of rapamycin inhibitors (mTORi), for steroid avoidance and the need for a reduction to CNI exposure emerged from the consensus process. A selected list of unmet needs prompting further investigations have also been developed. The so far heterogeneous and granular approach to immunosuppression in oncologic patients deserves greater efforts for a more standardized therapeutic response to the different clinical scenarios. This consensus process makes a first unprecedented step in this direction, to be developed on a larger scale.

Current Use of Immunosuppression in Liver Transplantation

Since the first successful liver transplant in 1967, immunosuppression has allowed liver transplantation to become the standard treatment of end-stage liver disease. Over the decades, the rates of rejection have decreased, and patient survival outcomes have significantly improved in large part due to the introduction and advancements of immunosuppression medications. However, the adverse effects associated with long-term immunosuppression have created new challenges facing liver transplantation and added significantly to posttransplantation morbidity. This review presents the data and rationale for immunosuppression approaches, addresses the main controversies related to immunosuppression in liver transplantation, and explores some of the newer advancements in immunosuppressive drug therapy.

Role of the immune system in liver transplantation and its implications for therapeutic interventions

Liver transplantation (LT) stands as the gold standard for treating end-stage liver disease and hepatocellular carcinoma, yet postoperative complications continue to impact survival rates. The liver's unique immune system, governed by a microenvironment of diverse immune cells, is disrupted during processes like ischemia-reperfusion injury posttransplantation, leading to immune imbalance, inflammation, and subsequent complications. In the posttransplantation period, immune cells within the liver collaboratively foster a tolerant environment, crucial for immune tolerance and liver regeneration. While clinical trials exploring cell therapy for LT complications exist, a comprehensive summary is lacking. This review provides an insight into the intricacies of the liver's immune microenvironment, with a specific focus on macrophages and T cells as primary immune players. Delving into the immunological dynamics at different stages of LT, we explore the disruptions after LT and subsequent immune responses. Focusing on immune cell targeting for treating liver transplant complications, we provide a comprehensive summary of ongoing clinical trials in this domain, especially cell therapies. Furthermore, we offer innovative treatment strategies that leverage the opportunities and prospects identified in the therapeutic landscape. This review seeks to advance our understanding of LT immunology and steer the development of precise therapies for postoperative complications.

Ethnic disparities in waitlist outcomes of patients with nonalcoholic steatohepatitis listed for liver transplantation in the US

NASH is the fastest-growing cause of liver cirrhosis and is the leading indication for liver transplantation (LT). However, significant racial and ethnic disparities in waitlist outcomes and LT allocation may unfairly disadvantage minorities. Our aim was to characterize racial and ethnic disparities in waitlist mortality and transplantation probability among patients with NASH. This is a retrospective analysis of the United Network for Organ Sharing registry data of LT candidates from January 1, 2000 to December 31, 2021. Outcomes analysis was performed using competing risk analysis with the Fine and Gray model. The multivariable adjustment was conducted, and mixed-effect regression was used to compare the model for end-stage liver disease scores at listing and removal. Of 18,562 patients with NASH cirrhosis, there were 14,834 non-Hispanic Whites, 349 African Americans, 2798 Hispanics, 312 Asians, and 269 of other races/ethnicities; African American (effect size: 2.307, 95% CI: 1.561-3.053, and p < 0.001) and Hispanic (effect size: 0.332, 95% CI: 0.028-0.637, p = 0.032) patients were found to have a significantly higher model for end-stage liver disease scores at the time of listing than non-Hispanic Whites. African Americans had a higher probability of receiving LT relative to non-Hispanic Whites (subdistribution HR: 1.211, 95% CI: 1.051-1.396, and p = 0.008). However, Hispanic race/ethnicity was associated with a lower transplantation probability (subdistribution HR: 0.793, 95% CI: 0.747-0.842, and p < 0.001) and increased waitlist mortality (subdistribution HR: 1.173, CI: 1.052-1.308, and p = 0.004) compared with non-Hispanic Whites. There are significant racial and ethnic disparities in waitlist outcomes of patients with NASH in the US. Hispanic patients are less likely to receive LT and more likely to die while on the waitlist compared with non-Hispanic Whites despite being listed with a lower model for end-stage liver disease scores.

Liver Transplantation for Primary Sclerosing Cholangitis (PSC) With or Without Inflammatory Bowel Disease (IBD)-A European Society of Organ Transplantation (ESOT) Consensus Statement

Primary sclerosing cholangitis (PSC) is the classical hepatobiliary manifestation of inflammatory bowel disease (IBD) and a lead indication for liver transplantation (LT) in the western world. In this article, we present a Consensus Statement on LT practice, developed by a dedicated Guidelines' Taskforce of the European Society of Organ Transplantation (ESOT). The overarching goal is to provide practical guidance on commonly debated topics, including indications and timing of LT, management of bile duct stenosis in patients on the transplant waiting list, technical aspects of transplantation, immunosuppressive strategies post-transplant, timing and extension of intestinal resection and futility criteria for re-transplantation.

Vessels that encapsulate tumour clusters vascular pattern in hepatocellular carcinoma

Vessels that encapsulate tumour clusters (VETC) is a distinct histologic vascular pattern associated with a novel mechanism of metastasis. First described in human cancers in 2004, its prevalence and prognostic significance in hepatocellular carcinoma (HCC) has only been appreciated in the past decade with a rapidly increasing body of literature. A robust biomarker of aggressive disease, the VETC pattern is easy to recognise but relies on histologic examination of tumour tissue for its diagnosis. Radiological recognition of the VETC pattern is an area of active research and is becoming increasingly accurate. As a prognostic marker, VETC has consistently proven to be an independent predictor of disease recurrence and overall survival in patients with HCC undergoing resection and liver transplantation. It can also guide treatment by predicting response to other therapies such as transarterial chemoembolisation and sorafenib. Without prospective randomised-controlled trials or routine evaluation of VETC in clinical practice, there are currently no firm treatment recommendations for VETC-positive tumours, although some perspectives are provided in this review based on the latest knowledge of their pathogenesis - a complex interplay between tumour angiogenesis and the immune microenvironment. Nevertheless, VETC has great potential as a future biomarker that could take us one step closer to precision medicine for HCC.

Therapeutic Effects of Anti-PD1 Immunotherapy on Hepatocellular Carcinoma Under Administration of Tacrolimus

BACKGROUND

Liver transplantation (LT) is the treatment of choice for patients with hepatocellular carcinoma (HCC). Recurrence of HCC after LT occurs in 10% to 20% of cases. Preclinical studies to evaluate immune checkpoint inhibitors in conjunction with immunosuppressant treatment in transplant recipients have been lacking. Here, we evaluated the efficacy, safety, and mechanism of programmed cell death-1 (PD1) blockade under tacrolimus treatment in transplant recipients.

METHODS

We used a murine allogeneic skin transplantation model and murine syngeneic subcutaneous and orthotopic HCC models and measured the tumor volume and the change in tumor-infiltrating lymphocytes under PD1 blockade and tacrolimus treatment.

RESULTS

Tacrolimus treatment prolonged allograft survival in the allogeneic transplantation model and enhanced tumor growth in both subcutaneous and orthotopic HCC models. PD1 blockade suppressed tumor growth and lung metastasis in correlation with the number of infiltrating CD8 + T cells. Under tacrolimus treatment, PD1 blockade still resulted in an antitumor effect accompanied by a significant increase in tumor-infiltrating CD8 + T cells, natural killer cells, dendritic cells, and natural killer T cells. Tacrolimus treatment rescued the acceleration of transplant rejection induced by PD1 blockade in the allogeneic transplantation model.

CONCLUSIONS

Our data suggest that treatment with high-dose tacrolimus in conjunction with PD1 blockade has an antitumor effect and reduces transplant rejection in mouse models of allograft skin transplantation and HCC. Thus, these results suggest that a clinical trial of PD1 inhibitors for HCC in LT merits consideration.

Immunotolerance in liver transplantation: a primer for the clinician

The use of immunosuppressive medications for solid organ transplantation is associated with cardiovascular, metabolic, and oncologic complications. On the other hand, the development of graft rejection is associated with increased mortality and graft dysfunction. Liver transplant recipients can withdraw from immunosuppression without developing graft injury while preserving an adequate antimicrobial response - a characteristic known as immunotolerance. Immunotolerance can be spontaneously or pharmacologically achieved. Contrary to the classic dogma, clinical studies have elucidated low rates of true spontaneous immunotolerance (no serologic or histological markers of immune injury) among liver transplant recipients. However, clinical, serologic, and tissue biomarkers can aid in selecting patients in whom immunosuppression can be safely withdrawn. For those who failed an immunosuppression withdrawal trial or are at high risk of rejection, pharmacological interventions for immunotolerance induction are under development. In this review, we provide an overview of the mechanisms of immunotolerance, the clinical studies investigating predictors and biomarkers of spontaneous immunotolerance, as well as the potential pharmacological interventions for inducing it.

Long-term Care of the Adult Liver Transplant Recipient

While outcomes after liver transplantation have increased over the last two decades, this is primarily as a consequence of a reduction in early deaths and survival of those who survive the first 6 months has not significantly changed. Causes of premature death and graft loss include cardiovascular disease, renal impairment, malignancy and some infections. As the number of transplant recipients increase, care is being given by primary and secondary care clinicians. Management of the well patient is crucially dependent on careful assessment and where appropriate intervention, especially of cardiovascular risk - such as advice about avoidance of weight gain; management of hypertension, hyperlipidaemia and diabetes; and provision of appropriate lifestyle advice. Other interventions include surveillance for de novo malignancies, active management of immunosuppressive regimen with the need to tailor immunosuppression to the individual. Prompt investigation of abnormalities of liver function is essential. Immune-mediated graft damage still occurs but is less common as a cause for graft loss. Adherence is sometimes an issue, especially in teenagers and young adults, and should be considered and support given where needed. Immunisations (avoiding live and attenuated vaccines) should be encouraged. Recurrence of disease remains an issue, and some interventions (such as appropriate use of antiviral therapy for those grafted with viral hepatitis, use of ursodeoxycholic acid for those grafted for primary biliary cholangitis or long-term steroids for those grafted for autoimmune disease) may improve and maintain graft function. Close collaboration between recipient and the attending clinicians in primary, secondary and tertiary care and close attention to modifiable conditions will lead to improved outcomes.

Association between vessels that encapsulate tumour clusters vascular pattern and hepatocellular carcinoma recurrence following liver transplantation

BACKGROUND

Vessels that encapsulate tumor clusters (VETC) is a novel vascular pattern seen on hepatocellular carcinoma (HCC) histology which has been shown to independently predict tumor recurrence and survival after liver resection. Its prognostic value in HCC patients receiving liver transplantation (LT) is unclear.

METHODS

We retrospectively studied consecutive adults who underwent deceased-donor LT with active HCC found on explant between 2010-2019. Tumor tissue was stained for CD34 and quantified for VETC. Primary and secondary endpoints were time to recurrence (TTR) and recurrence-free survival (RFS).

RESULTS

During the study period, 158 patients received LT where HCC was present on explant. VETC pattern was seen in 76.5% of explants. Patients with VETC-positive tumors spent longer on the waitlist (6.4 vs. 4.1 months, P=0.048), had higher median tumor numbers (2 vs. 1, P=0.001) and larger tumor sizes (20mm vs. 13mm, P<0.001) on explant pathology compared to those with VETC-negative tumors. Correspondingly, VETC-positive patients were more likely to be outside of accepted LT criteria for HCC. After 56.4 months median follow-up, 8.2% of patients developed HCC recurrence post-LT. On multivariable Cox regression, presence of VETC pattern did not predict TTR or RFS. However, the number of VETC-positive tumors on explant was an independent predictor of TTR (hazard ratio [HR] 1.411, P=0.001) and RFS (HR 1.267, P=0.014) after adjusting for other significant variables.

CONCLUSION

VETC pattern is commonly observed in HCC patients undergoing LT. The number of VETC-positive tumors, but not its presence, is an independent risk factor for TTR and RFS post-LT.

The Importance of the Immunosuppressive Regime on Hepatocellular Carcinoma Recurrence After Liver Transplantation

PURPOSE

Hepatocellular carcinoma (HCC) recurrence after liver transplantation (LT) occurs in approximately 20% of recipients and these patients have median about one year survival after diagnosis. Some immunosuppressive drugs can cause development of HCC recurrence, on the other hand some immunosuppressive drugs may have a positive effect for preventing HCC recurrence. Thus, immunosuppression (IS) modification may play a role in preventing HCC recurrence.

METHODS

In this review, we analyzed IS treatment strategy in two parts: before HCC recurrence following LT and after HCC recurrence following LT, and after HCC recurrence following LT.

RESULTS

There is no proven, optimal IS protocol to prevent HCC recurrence after transplantation. Therefore, individualized immunosuppressive treatments should be tailored to the biological behaviour of HCC. Forcing the immune tolerance in terms of recurrence can probably be expressed as the most appropriate post LT period. Once HCC recurrence has developed after transplantation, again, there is no commonly accepted, optimal IS treatment, but there is a tendency to switch to IS modifications that include mTORi by minimizing CNIs and MMF.

CONCLUSION

There is a need for well-designed, randomized, controlled clinical studies with larger numbers of patients on this subject.

Distribution evaluation of tacrolimus in the ascitic fluid of liver transplant recipients with liver cirrhosis by a sensitive ultra-performance liquid chromatography-tandem mass spectrometry method

Tacrolimus has a narrow therapeutic index and large individual differences in pharmacokinetics. The distribution of tacrolimus in ascitic fluid and its influence on whole-blood tacrolimus were unclear. In this study, a sensitive ultra-performance liquid chromatography-tandem mass spectrometry method was established and validated for the quantification of tacrolimus in the ascitic fluid of liver transplant recipients. Chromatographic separation was achieved on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column (2.1 × 100 mm, 3.5 μm). Mass spectrometry was performed in multiple reaction monitoring conditions of transitions m/z 821.4→768.5 for tacrolimus. The concentrations of tacrolimus in the ascitic fluid range from 0.2 to 3.0 ng/mL, accounting for 1.19-31.87% of whole-blood tacrolimus concentrations. A linear mixed model showed a statistically significant positive correlation between the steady-state trough blood concentration of tacrolimus and the corresponding amount of tacrolimus excreted in the ascitic fluid for 24 consecutive hours, especially after normalization by daily dose per unit body weight. These data suggested that the distribution of tacrolimus in the ascitic fluid has great individual differences. The whole-blood tacrolimus concentration, dose per unit body weight, and other confounding factors may contribute to the excretion of tacrolimus in ascitic fluid, but the influence of tacrolimus excretion in drained ascitic fluid on the whole-blood tacrolimus concentration is negligible.

Antibody-Mediated Rejection in Adult Liver Transplant Recipients: A Case Series and Literature Review

Antibody-mediated rejection is a rare complication following liver transplantation and there is a lack of a comprehensive treatment strategy to provide detailed information about the dose and duration of antibody-mediated rejection treatment. This study describes eight adult liver transplantation recipients who developed antibody-mediated rejection between 2002 and 2021 in our center, as well as a review of the literature on the reported cases of antibody-mediated rejection in liver transplantation recipients. Our center's medical records were reviewed retrospectively to extract the necessary data on patients' characteristics, management, and outcomes. Then, a comprehensive search using Embase, PubMed, Web of Science, Cochrane library, and Google Scholar databases was conducted without time limitation until June, 2021. Finally, a stepwise protocol was developed for managing acute, chronic, and recurrent antibody-mediated rejection in liver transplantation patients, based on our own experience, reported cases in the literature, and data from kidney transplantation. By review of the literature, 24 case studies containing 64 patients were identified and their management strategies and outcomes were evaluated. Although, various combinations of corticosteroids, plasma exchange, intravenous immunoglobulin, and biological agents are used in the treatment of acute antibody-mediated rejection in liver transplantation, treatment strategies should be classified according to the type, severity, and the timing of its onset. Given the importance of early treatment, rituximab and/or bortezomib should be started as soon as possible if no improvement in liver enzymes/bilirubin is observed during the initial treatment strategy using corticosteroids, plasma exchange and intravenous immunoglobulin. This article is protected by copyright. All rights reserved.

The Underutilization, Adverse Reactions and Efficacy of Statins after Liver Transplant: A Meta-Analysis and Systematic Review

(1) Background: Treatment of dyslipidemia via statin therapy in the non-liver transplant (LT) population is associated with a mortality benefit; however, the impact of statin therapy in post-LT population is not well-defined. This meta-analysis seeks to investigate the safety and efficacy of statin therapy in post-LT patients. (2) Methods: A systematic literature search on Medline and EMBASE database was conducted. A single-arm proportional meta-analysis and conventional pair-wise meta-analysis were performed to compare different outcomes with a random effects model. (3) Results: A total of 11 studies were included in this study, with 697 LT recipients identified to be on statin therapy. Statins were underutilized with only 32% (95% CI: 0.15–0.52) of 1094 post-LT patients on therapy. The incidence of adverse events of 14% (95% CI: 0.05–0.25) related to statin therapy was low. A significant mortality benefit was noted in patients on statin therapy with HR = 0.282 (95% CI: 0.154–0.517, p < 0.001), and improved lipid profiles post LT. The use of statins also significantly decreased odds of graft rejection (OR = 0.33; 95% CI: 0.15–0.73) and hepatocellular carcinoma (HCC) recurrence (HR = 0.32, 95% CI: 0.11–0.89). (4) Conclusions: Statin therapy is safe and efficacious in post-LT patients. Future studies to evaluate the effects of interactions between statins and immunosuppressant therapy are warranted.

Efficacy and Safety of Everolimus With Reduced Tacrolimus in Liver Transplant Recipients: 24-month Results From the Pooled Analysis of 2 Randomized Controlled Trials

BACKGROUND AND METHODS

Data from 2 randomized liver transplant trials (N = 772; H2304 [deceased donor, n = 488], H2307 [living donor, n = 284]) were pooled to further evaluate the efficacy and safety of everolimus with reduced tacrolimus (EVR + rTAC) versus standard tacrolimus (sTAC) regimen at month 24.

RESULTS

EVR + rTAC was comparable to sTAC for composite efficacy failure of treated biopsy-proven acute rejection, graft loss, or death (9.8% versus 10.8%; difference, -1.0%; 95% confidence interval, -5.4 to 3.4; P = 0.641) at month 24. EVR + rTAC was superior to sTAC for the mean change in estimated glomerular filtration rate (eGFR) from randomization to month 24 (-8.37 versus -13.40 mL/min/1.73 m2; P = 0.001). A subanalysis of renal function by chronic kidney disease (CKD) stage at randomization showed significantly lower decline in eGFR from randomization to month 24 for patients with CKD stage 1/2 (eGFR ≥ 60 mL/min/1.73 m2) in EVR + rTAC group versus sTAC (-12.82 versus -17.67 mL/min/1.73 m2, P = 0.009). In patients transplanted for hepatocellular carcinoma (HCC) beyond Milan criteria, HCC recurrence was numerically lower although not statistically significant with EVR + rTAC versus sTAC group (5.9% [1 of 17] versus 23.1% [6 of 26], P = 0.215), while comparable in patients within Milan criteria (2.9% [3 of 102] versus 2.1% [2 of 96], P = 1.000), irrespective of pretransplant alpha-fetoprotein levels.

CONCLUSIONS

EVR + rTAC versus sTAC showed comparable efficacy and safety with significantly better renal function, particularly in patients with normal/mildly decreased renal function (CKD stage 1/2) at randomization and a trend toward lower HCC recurrence in patients transplanted with HCC beyond Milan at month 24. Further long-term data would be required to confirm these results.

A systematic review and meta-analysis on the incidence of osteoporosis and fractures after liver transplant

Following liver transplant (LT), osteoporosis is a severe complication that causes morbidity. However, the incidence and risk factors of osteoporosis and fractures have not been well described. Single-arm meta-analysis of studies reporting osteopenia, osteoporosis, and fractures post-LT was performed with meta-regression for study period. Dichotomous variables, continuous variables and time-to-event variables were pooled in odds ratio, weighted mean difference and hazard ratio, respectively. For risk factors with limited data, a systematic review of literature was conducted. There was a significant increase in both osteoporosis and fractures compared to non-LT patients. Osteopenia, osteoporosis and incident fractures were newly diagnosed in 34.53% (CI: 0.17-0.56, n = 301), 11.68% (CI: 0.05-0.24, n = 1251) and 20.40% (CI: 0.13-0.30, n = 4322) of LT patients, respectively. Female gender (P = 0.017) increased risks of osteoporosis but not older age and BMI. Older age, lower pre-LT bone mineral density (BMD), presence of bone disease pre-LT were significant risk factors for fractures but not female gender, post-menopausal state, BMI, smoking and alcohol. There is a high incidence of skeletal complications post-LT. Older age, lower pre-LT BMD and presence of bone disease pre-LT are significant risk factors that are associated with incident fractures physicians should be cognisant of in liver transplant recipients.

A Time-Based Meta-Analysis on the Incidence of New Onset Diabetes after Liver Transplantation

NODAT (new-onset diabetes after transplantation) is an important complication after liver transplant, however, there is variation in the reported incidence of NODAT. Therefore, a meta-analysis was performed to estimate the incidence of NODAT in liver transplant. Electronic databases were searched for articles regarding NODAT incidence after liver transplantation. Incidence of NODAT were analyzed at six different timepoints. Summary statistics were calculated using a generalized linear mixed model in random effects. 28 articles were included and out of a pooled population of 71,257 patients, overall incidence of NODAT was found to be 15.51%, 16.09%, 18.30%, 20.86%, 18.08%, 25.05% for three-months, six-months, one-year, three-year, five-year, and ten-year timepoints respectively. After a sensitivity analysis which only included articles with clear definitions of NODAT, the incidence of NODAT was found to be higher at three-year (21.79%), five-year (25.82%), and ten-year (44.95%) timepoints. Subgroup analysis according to ethnicity found no significant differences for all timepoints. However, studies with predominantly Asian participants generally had a higher incidence of NODAT. In conclusion, this meta-analysis provides a pooled estimate of the incidence of NODAT following liver transplantation. Further studies are required to provide a more comprehensive understanding on how ethnicity can affect the incidence of NODAT.

In-hospital mortality of liver transplantation and risk factors: a single-center experience

Background

Liver transplantation (LT) is a life-saving treatment for patients with end-stage liver disease and acute liver failure. However, in-hospital death cannot be avoided. We designed this study to analyze patients' in-hospital mortality rate after LT and the factors correlated with in-hospital death.

Methods

The data of patients who received LT in our hospital between January 11, 2015, and November 19, 2019, were obtained from the China Liver Transplant Registry and medical records. The in-hospital mortality rate was calculated, and factors related to mortality, cause of death, and factors related to cause of death were analyzed by reviewing patients' data.

Results

A total of 529 patients who underwent cadaveric LT were enrolled in this study. Modified piggyback orthotopic LT was performed for all patients. Seventy patients died in the hospital after LT, and the in-hospital mortality rate was 13.2%. Factors including model for end-stage liver disease (MELD) score, Child-Pugh grading, intraoperative blood loss, and anhepatic phase were correlated with in-hospital death. MELD score and intraoperative blood loss were determined as the two independent risk factors of in-hospital death. The first two causes of death were infection (34.3%) and primary non-function (15.7%). Pulmonary fungal infection was the main cause of infectious death. MELD score was the independent risk factor for infectious death, and both body mass index of donors and cold ischemic time were independent risk factors of primary non-function.

Conclusions

In-hospital death poses a threat to certain patients undergoing LT. Our study suggests that the main cause of in-hospital death is an infection, followed by primary non-function.

A Meta-Analysis on the Rate of Hepatocellular Carcinoma Recurrence after Liver Transplant and Associations to Etiology, Alpha-Fetoprotein, Income and Ethnicity

Hepatocellular carcinoma (HCC) recurrence after liver transplant is associated with a poor prognosis and significantly increases morbidity and mortality among liver transplant patients. Therefore, this meta-analysis aims to evaluate the overall prevalence of HCC recurrence following liver transplant. Medline and Embase databases were searched, and a meta-analysis of proportions was conducted. Observational studies reporting the prevalence of recurrent hepatocellular carcinoma (HCC) after liver transplant were included, with the analysis being stratified by adherence to Milan criteria, ethnicity, socio-economic status, alpha fetoprotein (AFP) levels, living donor vs. deceased donor, and the underlying aetiology of the liver disease. A meta-regression on the date of the study completion was also performed. Of a total 40,495 patients, 3888 developed an HCC recurrence. The overall prevalence of recurrent HCC was 13% (CI: 0.12-0.15). Patients beyond the Milan criteria (MC) were more likely to recur than patients within MC. Asian populations had the greatest prevalence of HCC recurrence (19%; CI: 0.15-0.24) when compared to Western (12%; CI: 0.11-0.13) and Latin American populations (11%; CI: 0.09-0.14). The prevalence of recurrent HCC was the highest in patients infected with hepatitis B virus (HBV) (18%; CI: 0.11-0.27) compared to other aetiologies. A higher AFP also resulted in an increased recurrence. This highlights interesting differences based on ethnicity, income, and aetiology, and further studies are needed to determine the reasons for the disparity.

The current status and outcomes of pediatric liver transplantation in western China: A multi-center retrospective study

This retrospective study was conducted to examine the development and current status of pediatric liver transplantation (LT) in western China. Clinical, demographic, morbidity, and mortality data were collected to analyze. It included 260 consecutive pediatric LTs performed at three centers in western China between January 2000 and May 2019. Kaplan-Meier graft survival rates at 1, 3, 5, and 10 years were 82.1%, 77.2%, 76.6%, and 76.6%, respectively; corresponding patient survival rates were 84.7%, 80.7%, 80.0%, and 80.0%, respectively. More patients underwent living donor liver transplantation (LDLT; n = 188 (73.4%)) than deceased-donor liver transplantation (DDLT; n = 68 (26.6%)). Survival was better after LDLT (91.5%, 86.6%, and 80.6% at 1, 3, and 5 years, respectively) than after DDLT (80.9%, 72.4%, and 63.9%, respectively; P < .05). Biliary atresia was the leading LT indication (n = 141 (55.1%)), followed by metabolic disease (n = 36 (14.1%)), which was associated with the best recipient survival (88.5% at 5 years). The transplant era and graft-to-recipient body weight ratio (GRWR) also significantly predicted overall survival. Survival rates at 5 years were worst in 2000-2005 (54.5%) and best for GRWRs of 0.8%-4% (80.4%). The development of pediatric LT in western China began slowly, but the quantity and quality of pediatric LT has progressed in recent years. This procedure is now a promising and reliable treatment for children with end-stage liver disease in western China.

The use of induction therapy in liver transplantation is highly variable and is associated with posttransplant outcomes

The use of induction immunosuppression in liver transplantation (LT) remains controversial. This was a retrospective cohort study of adult, first-time liver-alone recipients (N = 69 349) at 114 US centers between 2005 and 2018 using data from the United Network for Organ Sharing. The comparative effectiveness of nondepleting and depleting induction (NDI and DI) was assessed. Overall, 27% of recipients received induction with 65.7% of the variance in the receipt of induction being attributed to transplant center alone. NDI and DI were associated with a lower risk of death/graft failure compared to no induction (adjusted hazard ratio 0.90 [95% confidence interval (CI): 0.86-0.95] and 0.91 [95% CI: 0.85-0.97], respectively; P < .001). In nondialysis recipients at the mean transplant estimated glomerular filtration rate (eGFR), NDI was associated with an adjusted gain in eGFR by 6 months of +3.8 mL/min per 1.73 m² and DI of +3.33 mL/min per 1.73 m² compared to no induction (P < .001). Recipients with lower eGFR at LT had greater predicted improvement in eGFR (interaction P < .001). Only NDI was associated with a reduced risk of acute rejection in the first year post-LT (odds ratio 0.87, 95% CI: 0.8-0.94). Significant variability in induction practices exists, with center being a major determinant. The absolute incremental benefits of NDI and DI over no induction were small.