Liver transplantation in Germany

Viability assessment and transplantation of extended criteria donor liver grafts using normothermic machine perfusion

BACKGROUND

The scarcity of available liver grafts necessitates the use of organs from extended criteria donors, a practice associated with an increased risk of graft failure. A notable percentage of deceased donor liver allografts are rejected due to subjective criteria. Normothermic machine perfusion holds promise for introducing objective parameters into this decision-making process. The aim of this study was to compare the outcomes of standard criteria and extended criteria donor allografts after liver transplantation, following viability assessment, using normothermic machine perfusion.

METHODS

Liver allografts preserved by normothermic machine perfusion before liver transplantation at the University Hospital of Münster were retrospectively analyzed. Organs were stratified according to the Eurotransplant Donor Risk Index. In total, 101 liver grafts were included in this study and divided into 2 groups: (1) standard criteria donors with a Donor Risk Index <1.8 (DRI-low) and (2) extended criteria donors with a Donor Risk Index ≥1.8 (DRI-high).

RESULTS

An increased risk profile of donor livers, as assessed by the Eurotransplant Donor Risk Index, did not correlate with patient or graft survival. High-risk liver grafts were effectively transplanted into recipients with different risk levels after viability assessment by normothermic machine perfusion. However, the recipients' model for end-stage liver disease scores showed a significant association with both overall patient and graft survival.

CONCLUSION

The use of normothermic machine perfusion for viability assessment allows safe transplantation of high-risk donor livers and effectively addresses the disparity between donor liver availability and transplantation demand.

Detrimental impact of immunosuppressive burden on clinical course in patients with Cytomegalovirus infection after liver transplantation

INTRODUCTION

Cytomegalovirus (CMV)-infection and reactivation remain a relevant complication after liver transplantation (LT). The recipient and donor serum CMV-IgG-status has been established for risk stratification when choosing various pharmaceutical regimens for CMV-prophylaxis in the last two decades. However, factors influencing course of CMV-infection in LT remain largely unknown. In this study, the impact of immunosuppressive regimen was examined in a large cohort of patients.

METHODS

All patients that underwent primary LT between 2006 and 2018 at the Charité-Universitaetsmedizin, Berlin, were included. Clinical course as well as histological and laboratory findings of patients were analyzed our prospectively maintained database. Univariate and multivariate regression analysis for impact of variables on CMV-occurrence was conducted, and survival was examined using Kaplan-Meier analysis.

RESULTS

Overall, 867 patients were included in the final analysis. CMV-infection was diagnosed in 325 (37.5%) patients after transplantation. Significantly improved overall survival was observed in these patients (Log rank = 0.03). As shown by correlation and regression tree classification and regression tree analysis, the recipient/donor CMV-IgG-status with either positivity had the largest influence on CMV-occurrence. Analysis of immunosuppressive burden did not reveal statistical impact on CMV-infection, but statistically significant inverse correlation of cumulative tacrolimus trough levels and survival was found (Log rank < .001). Multivariate analysis confirmed these findings (p = .02).

DISCUSSION

CMV-infection remains of clinical importance after LT. Undergone CMV-infection of either recipient or donor requires prophylactic treatment. Additionally, we found a highly significant, dosage-dependent impact of immunosuppression (IS) on long-term outcomes for these patients, underlying the importance of minimization of IS in liver transplant recipients.

Epidemiology of liver transplantation and post-LT complications in Germany: nationwide study (2005-2018)

BACKGROUND

To date, liver transplantation (LT) is the only curative treatment for cirrhosis and early-diagnosed progressive acute liver failure (ALF). However, LT results in morbidities and mortality even post-LT. Different comorbidities may follow and further increase mortality and morbidity. In this study, we investigated the outcomes and their trends over a period of 14 years among hospitalized patients evaluated for LT, transplant and post-LT in Germany.

METHODS

This German nationwide study investigated the number of admissions of patients hospitalized for evaluation of LT and post-LT on related comorbidities and complications between 2005 and 2018 based on the DRG system with ICD-10/OPS codes. 14 745 patients were put on the LT waiting list and 12 836 underwent LT during the observational period.

RESULTS

The LT number decreased by 2.3% over time, while the waiting list mortality rate increased by 5%. By contrast, the in-hospital mortality rate decreased by 3%, especially in ALF patients (decrease of 16%). Interestingly, admissions of post-LT patients for complications almost doubled, driven mainly by complications of immunosuppression (tripled). Importantly, post-LT patients with acute kidney injury (20.2%) and biliodigestive anastomosis (18.4%) showed the highest in-hospital mortality rate of all complications.

CONCLUSION

In conclusion, the decrease in LT leads most probably to the increased in-hospital mortality of patients on the waiting list. Interestingly, in-hospital mortality decreased in LT patients. Post-LT comorbidities requiring hospitalization increased in the observational period and management of patients post-LT with AKI or biliodigestive anastomosis should be addressed.

Advances and Controversies in Acute Alcohol-Related Hepatitis: From Medical Therapy to Liver Transplantation

Alcohol-related hepatitis (AH) is a clinical syndrome characterized by recent-onset jaundice in the context of alcohol consumption. In patients with severe AH "unresponsive" to steroid therapy, mortality rates exceed 70% within six months. According to European and American guidelines, liver transplantation (LT) may be considered in highly selected patients who do not respond to medical therapy. The aim of this narrative review is to summarize current knowledge from medical therapy to liver transplantation in acute alcohol-related hepatitis. Due to the impossibility to guarantee six-month abstinence, LT for AH is controversial. Principal concerns are related to organ scarcity in the subset of stigma of "alcohol use disorder" (AUD) and the risk of relapse to alcohol use after LT. Return to alcohol use after LT is a complex issue that cannot be assessed as a yes/no variable with heterogeneous results among studies. In conclusion, present data indicate that well-selected patients have excellent outcomes, with survival rates of up to 100% at 24 and 36 months after LT. Behavioral therapy, ongoing psychological support, and strong family support seem essential to improve long-term outcomes after LT and reduce the risk in relapse of alcohol use.

Regional transplant rates depend more on physician-dependent variables than on proximity to transplant center

PURPOSE

The objective of this work was to uncover inequalities in access to liver transplantation in Bavaria, Germany.

METHODS

For this purpose, the annual transplantation rate per 1 million inhabitants for the respective districts was determined from the aggregated postal codes of the place of residence of transplanted patients. The variables examined were proximity and travel time to the nearest transplant center, as well as the care category of the regional hospital. In addition, we assessed whether the head of gastroenterology at the regional hospital through which liver transplant candidates are referred was trained at a liver transplant center.

RESULTS

We could not demonstrate a direct relationship between proximity or travel time to the nearest transplant center and access to liver transplantation. Multivariate regression analysis shows that liver transplant training (p < 0.0001) of the chief physician (gastroenterologist) of the regional hospital was the most decisive independent factor for access to liver transplantation within a district.

CONCLUSION

We show that the transplant training experience of the head of gastroenterology at a regional hospital is an independent factor for the regional transplantation rate. Therefore, it appears important to maintain some liver transplant expertise outside the transplant centers in order to properly identify and assign potential transplant candidates for transplantation.

Outcomes following liver transplant for alcohol-associated liver disease: comparing alcohol-associated hepatitis and cirrhosis

BACKGROUND

Liver transplant (LT) is a highly effective therapy for refractory severe alcohol-associated hepatitis (SAH), but optimal selection criteria remain unknown. We aim to evaluate the outcomes of patients who received LT for alcohol-associated liver disease at our center following the introduction of updated selection criteria, including the removal of the minimum sobriety requirement.

METHODS

Data were collected on all patients who underwent LT for alcohol-associated liver disease from January 1, 2018, to September 30, 2020. Patients were divided into SAH and cirrhosis cohorts based on disease phenotype.

RESULTS

One hundred twenty-three patients underwent LT for alcohol-associated liver disease, including 89 (72.4%) for cirrhosis and 34 (27.6%) for SAH. There was no difference in 1- (97.1 ± 2.9% vs. 97.7 ± 1.6%, p = 0.97) and 3-year (97.1 ± 2.9% vs. 92.4 ± 3.4%, p = 0.97) survival between SAH and cirrhosis cohorts. Return to alcohol use was more frequent in the SAH cohort at 1 year (29.4 ± 7.8% vs. 11.4 ± 3.4%, p = 0.005) and 3 years (45.1 ± 8.7% vs. 21.0 ± 6.2%, p = 0.005) including higher frequencies of both slips and problematic drinking. Unsuccessful alcohol use counseling (HR 3.42, 95% CI 1.12-10.5) and prior alcohol support meetings (HR 3.01, 95% CI 1.03-8.83) predicted a return to harmful alcohol use patterns in early LT recipients. Both duration of sobriety (c-statistic 0.32 (95% CI 0.34-0.43) and SALT score (c-statistic 0.47, 95% CI 0.34-0.60) were independently poor predictors of return to harmful drinking.

CONCLUSION

Survival following LT was excellent in both SAH and cirrhosis cohorts. Higher rates of return to alcohol use highlight the importance of further individualized refinement of selection criteria and improved support following LT.

Platelets mediate acute hepatic microcirculatory injury in a protease-activated-receptor-4-dependent manner after extended liver resection

BACKGROUND

Small-for-size syndrome (SFSS) is a major complication following extended liver resection. The role of platelets in the early development of SFSS remains to be cleared. We aimed to investigate the impact of platelets and PAR-4, a receptor for platelet activation, on the acute phase microcirculatory injury after liver resection by in vivo microscopy analyzing the changes in leukocyte recruitment, platelet-neutrophil interaction, and microthrombosis-induced perfusion failure.

METHODS

Sixty-percent partial hepatectomy (PH) models using C57BL/6 mice receiving platelet depletion with anti-GPIbα, PAR-4 blockade with tcY-NH2, or vehicle treatment with saline were used. Sham-operated animals served as controls. Epifluorescence microscopic analysis was performed 2 h after PH to quantify the leukocyte recruitment and microcirculatory changes. Sinusoidal neutrophil recruitment, platelet-neutrophil interaction, and microthrombosis were evaluated using two-photon microscopy. ICAM-1 expression and liver liver injury were assessed in tissue/blood samples.

RESULTS

The increments of leukocyte recruitment in post-sinusoidal venules and sinusoidal perfusion failure, the upregulation of ICAM-1 expression, and the deterioration of liver function 2 h after 60% PH were alleviated in the absence of platelets or by PAR-4 blockade. Intensified platelet-neutrophil interaction and microthrombosis in sinusoids were observed 2 h after 60% PH, which significantly attenuated after PAR-4 blockade.

CONCLUSION

Platelets play a critical role in acute liver injury after extended liver resection within 2 h. The deactivation of platelets via PAR-4 blockade ameliorated liver function deterioration by suppressing early leukocyte recruitment, platelet-neutrophil interaction, and microthrombosis in hepatic sinusoids.

Ex Vivo Liver Machine Perfusion: Comprehensive Review of Common Animal Models

The most common preservation technique for liver grafts is static cold storage. Due to the organ shortage for liver transplantation (LT), extended criteria donor (ECD) allografts are increasingly used-despite the higher risk of inferior outcome after transplantation. Ex vivo liver machine perfusion (MP) has been developed to improve the outcome of transplantation, especially with ECD grafts, and is currently under evaluation in clinical trials. We performed a literature search on PubMed and ISI Web of Science to assemble an overview of rodent and porcine animal models of ex vivo liver MP for transplantation, which is essential for the present and future development of clinical liver MP. Hypothermic, subnormothermic, and normothermic MP systems have been successfully used for rat and pig LT. In comparison with hypothermic systems, normothermic perfusion often incorporates a dialysis unit. Moreover, it enables metabolic assessment of liver grafts. Allografts experiencing warm ischemic time have a superior survival rate after MP compared with cold storage alone, irrespective of the temperature used for perfusion. Furthermore, ex vivo MP improves the outcome of regular and ECD liver grafts in animal models. Small and large animal models of ex vivo liver MP are available to foster the further development of this new technology. Impact Statement Ex vivo machine perfusion is an important part of current research in the field of liver transplantation. While evidence for improve storage is constantly rising, the development of future applications such as quality assessment and therapeutic interventions necessitates robust animal models. This review is intended to provide an overview of this technology in common large and small animal models and to give an outlook on future applications. Moreover, we describe developmental steps that can be followed by others, and which can help to decrease the number of animals used for experiments based on the replace, reduce, refine concept.

Clinical characteristics of patients with non-alcoholic fatty liver disease (NAFLD) in Germany - First data from the German NAFLD-Registry

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) affects more than 18 million individuals in Germany. Real-world data help to better characterize the natural history of disease and standard of care.

METHODS

The German NAFLD-Registry is a prospective non-interventional study initiated by the German Liver Foundation and aims to describe clinical characteristics and observe outcomes in patients with NAFLD recruited in secondary and tertiary care.

RESULTS

From this ongoing study, baseline data of the first 501 patients (mean age 54 years, 48% women) were analysed. 13 % of the study population had a high risk for advanced fibrosis (FIB-4 ≥2.67), approximately one-third had a liver stiffness value ≥9.6kPa measured by transient elastography, and the clinical diagnosis of liver cirrhosis was present in 10%. Typical comorbidities were more prevalent in high risk as compared to low risk patients (FIB-4 <1.3) including arterial hypertension (85 vs. 42%), hypercholesterolemia (39 vs. 16%), and type 2 diabetes mellitus (T2DM) (69 vs. 26%). Patients with T2DM (192/501) had a higher NAFLD disease burden as shown by liver stiffness values ≥9.6 kPa (51%) and clinical diagnosis of cirrhosis (20%). Statins were used in 22% of the main population, while in diabetic patients, metformin, GLP-1 agonists, and SGLT2 inhibitors were used in 65, 17, and 17%, respectively. Uptake of life-style interventions such as physical exercise or nutritional counselling was generally low.

CONCLUSION

First data of the German NAFLD registry show that approximately every 10th patient has advanced NAFLD, highlights T2DM patients as a high-risk group and gives insights in the use of comedication and life-style interventions in secondary and tertiary care.

Liver Transplantation in Alcohol-related Liver Disease and Alcohol-related Hepatitis

Alcohol-related liver disease (ARLD) remains one of the leading causes of chronic liver disease and the prevalence of alcohol-related cirrhosis is still increasing worldwide. Thus, ARLD is one of the leading indications for liver transplantation (LT) worldwide especially after the arrival of direct-acting antivirals for chronic hepatitis C infection. Despite the risk of alcohol relapse, the outcomes of LT for ARLD are as good as for other indications such as hepatocellular carcinoma (HCC), with 1-, 5-, and 10- year survival rates of 85%, 74%, and 59%, respectively. Despite these good results, certain questions concerning LT for ARLD remain unanswered, in particular because of persistent organ shortages. As a result, too many transplantation centers continue to require 6 months of abstinence from alcohol for patients with ARLD before LT to reduce the risk of alcohol relapse even though compelling data show the poor prognostic value of this criterion. A recent pilot study even observed a lower alcohol relapse rate in patients receiving LT after less than 6 months of abstinence as long as addictological follow-up is reinforced. Thus, the question should not be whether LT should be offered to patients with ARLD but how to select patients who will benefit from this treatment.

Innate Immune Cells during Machine Perfusion of Liver Grafts-The Janus Face of Hepatic Macrophages

Machine perfusion is an emerging technology in the field of liver transplantation. While machine perfusion has now been implemented in clinical routine throughout transplant centers around the world, a debate has arisen regarding its concurrent effect on the complex hepatic immune system during perfusion. Currently, our understanding of the perfusion-elicited processes involving innate immune cells remains incomplete. Hepatic macrophages (Kupffer cells) represent a special subset of hepatic immune cells with a dual pro-inflammatory, as well as a pro-resolving and anti-inflammatory, role in the sequence of ischemia-reperfusion injury. The purpose of this review is to provide an overview of the current data regarding the immunomodulatory role of machine perfusion and to emphasize the importance of macrophages for hepatic ischemia-reperfusion injury.

Immunsuppression nach Organtransplantation: Essentials

Dieser Artikel soll einen Überblick über den Einsatz und mögliche Probleme der immunsuppressiven Therapie nach solider Organtransplantation (SOT) geben. Für einige Immunsuppressiva sind andere Empfehlungen bezüglich der angestrebten Talblutspiegel angegeben, als dies in der Fachinformation empfohlen ist. Wir möchten ausdrücklich darauf hinweisen, dass es sich hierbei um die persönliche Meinung der Autor*innen handelt.

Balancing Outcome vs. Urgency in Modern Liver Transplantation

Background

Current allocation mechanisms for liver transplantation (LT) overemphasize emergency, leading to poorer longtime outcomes. The utility was introduced to recognized outcomes in allocation. Recently, Molinari proposed a predictive outcome model based on recipient data.

Aims

The aims of this study were to validate this model and to combine it with the utility to emphasize outcome in allocation.

Methods

We retrospectively analyzed 734 patients who were transplanted between January 2010 and December 2019. Points were assigned as in Molinari's model and the score sum was correlated with observed 90-day mortality. The utility was calculated as the product of 1-year survival times 3-month mortality on the waiting list. The weighting of different compounds was introduced, and utility curves were calculated. Model for End-Stage Liver Disease (MELD) scores according to maximal utility were determined.

Results

In total, 120 patients (16.3%) had died within 90 days after LT. Higher MELD score, obesity, and hemodialysis prior to LT were confirmed risk factors. Overall survival was 83.8 and 77.4% after 90 days and 12 months, respectively. General utility culminated at MELD scores >35 in the overall population. Emphasizing the outcome shifted the maximal utility to lower MELD scores depending on Molinari scores.

Conclusions

Emphasizing outcome, at least in certain recipient risk categories, might improve the longtime outcomes and might be integrated into allocation models.

Over 30 Years of Pediatric Liver Transplantation at the Charité-Universitätsmedizin Berlin

Background: Pediatric liver transplantation (LT) is the treatment of choice for children with end-stage liver disease and in certain cases of hepatic malignancies. Due to low case numbers, a technically demanding procedure, the need for highly specialized perioperative intensive care, and immunological, as well as infectious, challenges, the highest level of interdisciplinary cooperation is required. The aim of our study was to analyze short- and long-term outcomes of pediatric LT in our center. Methods: We conducted a retrospective single-center analysis of all liver transplantations in pediatric patients (≤16 years) performed at the Department of Surgery, Charité – Universitätsmedizin Berlin between 1991 and 2021. Three historic cohorts (1991–2004, 2005–2014 and 2015–2021) were defined. Graft- and patient survival, as well as perioperative parameters were analyzed. The study was approved by the institutional ethics board. Results: Over the course of the 30-year study period, 212 pediatric LTs were performed at our center. The median patient age was 2 years (IQR 11 years). Gender was equally distributed (52% female patients). The main indications for liver transplantation were biliary atresia (34%), acute hepatic necrosis (27%) and metabolic diseases (13%). The rate of living donor LT was 25%. The median cold ischemia time for donation after brain death (DBD) LT was 9 h and 33 min (IQR 3 h and 46 min). The overall donor age was 15 years for DBD donors and 32 years for living donors. Overall, respective 1, 5, 10 and 30-year patient and graft survivals were 86%, 82%, 78% and 65%, and 78%, 74%, 69% and 55%. One-year patient survival was 85%, 84% and 93% in the first, second and third cohort, respectively (p = 0.14). The overall re-transplantation rate was 12% (n = 26), with 5 patients (2%) requiring re-transplantation within the first 30 days. Conclusion: The excellent long-term survival over 30 years showcases the effectiveness of liver transplantation in pediatric patients. Despite a decrease in DBD organ donation, patient survival improved, attributed, besides refinements in surgical technique, mainly to improved interdisciplinary collaboration and management of perioperative complications.

Molecular Surveillance of Carbapenem-Resistant Gram-Negative Bacteria in Liver Transplant Candidates

Background: Carbapenem-resistant Gram-negative bacteria (CRGN) cause life-threatening infections due to limited antimicrobial treatment options. The occurrence of CRGN is often linked to hospitalization and antimicrobial treatment but remains incompletely understood. CRGN are common in patients with severe illness (e.g., liver transplantation patients). Using whole-genome sequencing (WGS), we aimed to elucidate the evolution of CRGN in this vulnerable cohort and to reconstruct potential transmission routes.

Methods: From 351 patients evaluated for liver transplantation, 18 CRGN isolates (from 17 patients) were analyzed. Using WGS and bioinformatic analysis, genotypes and phylogenetic relationships were explored. Potential epidemiological links were assessed by analysis of patient charts.

Results: Carbapenem-resistant (CR) Klebsiella pneumoniae (n=9) and CR Pseudomonas aeruginosa (n=7) were the predominating pathogens. In silico analysis revealed that 14/18 CRGN did not harbor carbapenemase-coding genes, whereas in 4/18 CRGN, carbapenemases (VIM-1, VIM-2, OXA-232, and OXA-72) were detected. Among all isolates, there was no evidence of plasmid transfer-mediated carbapenem resistance. A close phylogenetic relatedness was found for three K. pneumoniae isolates. Although no epidemiological context was comprehensible for the CRGN isolates, evidence was found that the isolates resulted of a transmission of a carbapenem-susceptible ancestor before individual radiation into CRGN.

Conclusion: The integrative epidemiological study reveals a high diversity of CRGN in liver cirrhosis patients. Mutation of carbapenem-susceptible ancestors appears to be the dominant way of CR acquisition rather than in-hospital transmission of CRGN or carbapenemase-encoding genetic elements. This study underlines the need to avoid transmission of carbapenem-susceptible ancestors in vulnerable patient cohorts.

Effect of Aprotinin on Liver Injury after Transplantation of Extended Criteria Donor Grafts in Humans: A Retrospective Propensity Score Matched Cohort Analysis

The number of patients awaiting liver transplantation still widely exceeds the number of donated organs available. Patients receiving extended criteria donor (ECD) organs are especially prone to an aggravated ischemia reperfusion syndrome during liver transplantation leading to massive hemodynamic stress and possible impairment in organ function. Previous studies have demonstrated aprotinin to ameliorate reperfusion injury and early graft survival. In this single center retrospective analysis of 84 propensity score matched patients out of 274 liver transplantation patients between 2010 and 2014 (OLT), we describe the association of aprotinin with postreperfusion syndrome (PRS), early allograft dysfunction (EAD: INR 1,6, AST/ALT > 2000 within 7–10 days) and recipient survival. The incidence of PRS (52.4% vs. 47.6%) and 30-day mortality did not differ (4.8 vs. 0%; p = 0.152) but patients treated with aprotinin suffered more often from EAD (64.3% vs. 40.5%, p = 0.029) compared to controls. Acceptable or poor (OR = 3.3, p = 0.035; OR = 9.5, p = 0.003) organ quality were independent predictors of EAD. Our data do not support the notion that aprotinin prevents nor attenuates PRS, EAD or mortality.

Assessment of Donor Liver Pathology Predicts Survival After Liver Transplantation: A Retrospective Cohort Study

BACKGROUND

The aims of this study were to investigate the pathologic manifestation of pretransplant biopsy and to provide an accurate assessment method for liver graft of China Donation after Citizen's Death (CDCD).

METHODS

A retrospective analysis was performed based on clinical and biopsy data of 96 CDCD liver transplantations completed between January 2012 and December 2017. The pretransplant pathologic sections were semiquantitatively scored according to Banff Schema recommendations on liver allograft pathology. Graft overall survival (OS) and early allograft dysfunction (EAD) rates were observed.

RESULTS

The histologic analysis of the 96 CDCD liver graft biopsy specimens was summarized, including portal area neutrophilic infiltrate, macrovesicular steatosis, microvesicular steatosis, and hepatocellular swelling. Among these pathologic characteristics, only portal area neutrophilic infiltrate ≥20% was an independent risk factor for graft survival, although it has limited effect on the recipient's short-term prognosis.

CONCLUSIONS

We found that portal area neutrophilic infiltrate ≥20% was an independent risk factors for long-term graft survival. According to this criterion, we can identify liver transplant recipients at risk for poor prognosis and make timely interventions.

Early liver transplantation for acute alcoholic hepatitis: We can't say no

In patients with severe alcoholic hepatitis who are not responding to medical therapy, it is detrimental to postpone the decision to list a patient as there are no therapeutic alternatives. Early transplantation of patients with severe alcoholic hepatitis, using a restrictive selection process, has increasingly been used in the last decade with acceptable relapse rates. Indeed, early transplantation has gained the support of a growing number of experts from different countries, as shown by the European, American and Latin American recommendations. However, there is still great heterogeneity in its application between countries and even between centres within the same country.

Hospital Mortality and Current Trends in Liver Transplantation in Germany—a Systematic Analysis of Standardized Hospital Discharge Data, 2008–2017

BACKGROUND

Liver transplantation (LT) has undergone dynamic developments in recent decades. In Germany, the Federal Joint Committee (G-BA) recently tightened the guidelines regarding the minimum number of transplantations a center should perform annually. The aim of the study presented here, was to analyze recent trends in hospital mortality due to LT in Germany.

METHODS

Standardized hospital discharge data (2008-2017) from the Federal Statistical Office of Germany were used to establish hospital mortality after LT and case volume distribution among centers performing <20 LT annually (low volume centers, LVC), 20-49 LT (medium volume centers, MVC), and ≥ 50 LT (high volume centers, HVC).

RESULTS

Data from 9254 LT procedures were evaluated. The annual frequency of LT fell from n = 984 (2008) to n = 747 (2017), and over the same period the hospital mortality for all LT procedures went down from 15.8% to 11.0%. Hospital mortality was associated with age (<16 years: 5.3% to 60-69 years: 17.4%); however, there was no further increase in patients ≥ 70 years (16.5%). Univariate analysis revealed association of increased hospital mortality with liver disease etiology, the necessity for relaparotomy, and prolonged mechanical ventilation. The proportion of LT procedures performed in LVC and MVC increased and that in HVC decreased. LVC had higher hospital mortality than MVC/HVC, but this effect was dependent on patient age and disease etiology.

CONCLUSION

Our study showed that differences in mortality rate after LT among centers (LVC vs. MVC/HVC) were dependent on patient age and disease etiology. This should be taken into account when discussing the overall organization of LT in Germany.

Sensing Acute Cellular Rejection in Liver Transplant Patients Using Liver-Derived Extracellular Particles: A Prospective, Observational Study

Acute cellular rejection (ACR) after liver transplantation (LT) goes along with allograft dysfunction, which is diagnosed by liver biopsy and concomitant histological analysis, representing the gold standard in clinical practice. Yet, liver biopsies are invasive, costly, time-intensive and require expert knowledge. Herein we present substantial evidence that blood plasma residing peripheral liver-derived extracellular particles (EP) could be employed to diagnose ACR non-invasively. In vitro experiments showed organ-specific EP release from primary human hepatocytes under immunological stress. Secondly, analysis of consecutive LT patients (n=11) revealed significant heightened EP concentrations days before ACR. By conducting a diagnostic accuracy study (n = 69, DRKS00011631), we explored the viability of using EP as a liquid biopsy for diagnosing ACR following LT. Consequently, novel EP populations in samples were identified using visualization of t-distributed stochastic neighbor embedding (viSNE) and self-organizing maps (FlowSOM) algorithms. As a result, the ASGR1⁺CD130⁺Annexin V⁺ EP subpopulation exhibited the highest accuracy for predicting ACR (area under the curve: 0.80, 95% confidence interval [CI], 0.70-0.90), with diagnostic sensitivity and specificity of 100% (95% CI, 81.67-100.0%) and 68.5% (95% CI, 55.3-79.3%), respectively. In summary, this new EP subpopulation presented the highest diagnostic accuracy for detecting ACR in LT patients.

Treatment stage migration and treatment sequences in patients with hepatocellular carcinoma: drawbacks and opportunities

Purpose

This retrospective analysis focuses on treatment stage migration in patients with hepatocellular carcinoma (HCC) to identify successful treatment sequences in a large cohort of real-world patients.

Methods

1369 HCC patients referred from January 1993 to January 2020 to the tertiary center of the Heidelberg University Hospital, Germany were analyzed for initial and subsequent treatment patterns, and overall survival.

Results

The most common initial treatment was transarterial chemoembolization (TACE, n = 455, 39.3%) followed by hepatic resection (n = 303, 26.1%) and systemic therapy (n = 200, 17.3%), whereas the most common 2nd treatment modality was liver transplantation (n = 215, 33.2%) followed by systemic therapy (n = 177, 27.3%) and TACE (n = 85, 13.1%). Kaplan–Meier analysis revealed by far the best prognosis for liver transplantation recipients (median overall survival not reached), followed by patients with hepatic resection (11.1 years). Patients receiving systemic therapy as their first treatment had the shortest median overall survival (1.7 years; P < 0.0001). When three or more treatment sequences preceded liver transplantation, patients had a significant shorter median overall survival (1st seq.: not reached; 2nd seq.: 12.4 years; 3rd seq.: 11.1 years; beyond 3 sequences: 5.5 years; P = 0.01).

Conclusion

TACE was the most common initial intervention, whereas liver transplantation was the most frequent 2nd treatment. While liver transplantation and hepatic resection were associated with the best median overall survival, the timing of liver transplantation within the treatment sequence strongly affected median survival.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03528-3.

Colonization with multidrug-resistant organisms is associated with in increased mortality in liver transplant candidates

Objectives

Rising prevalence of multidrug-resistant organisms (MDRO) is a major health problem in patients with liver cirrhosis. The impact of MDRO colonization in liver transplantation (LT) candidates and recipients on mortality has not been determined in detail.

Methods

Patients consecutively evaluated and listed for LT in a tertiary German liver transplant center from 2008 to 2018 underwent screening for MDRO colonization including methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant gram-negative bacteria (MDRGN), and vancomycin-resistant enterococci (VRE). MDRO colonization and infection status were obtained at LT evaluation, planned and unplanned hospitalization, three months upon graft allocation, or at last follow-up on the waiting list.

Results

In total, 351 patients were listed for LT, of whom 164 (47%) underwent LT after a median of 249 (range 0–1662) days. Incidence of MDRO colonization increased during waiting time for LT, and MRDO colonization was associated with increased mortality on the waiting list (HR = 2.57, p<0.0001. One patients was colonized with a carbapenem-resistant strain at listing, 9 patients acquired carbapenem-resistant gram-negative bacteria (CRGN) on the waiting list, and 4 more after LT. In total, 10 of these 14 patients died.

Conclusions

Colonization with MDRO is associated with increased mortality on the waiting list, but not in short-term follow-up after LT. Moreover, colonization with CRGN seems associated with high mortality in liver transplant candidates and recipients.

Infections developing in patients undergoing liver transplantation: Recipients of living donors may be more prone to bacterial/fungal infections

BACKGROUND/AIMS

Despite surgical advances in liver transplantation and effective prophylactic strategies, posttransplant infections are the most important cause of morbidity and mortality. Diagnosis and management of infections because of developing immunosuppression is difficult and adversely affects mortality. This study aimed to review bacterial and fungal infections in patients after liver transplantation and to reveal the resistance rates.

MATERIALS AND METHODS

A total of 107 patients who underwent liver transplantation between January 2017 and February 2018 were evaluated retrospectively with regard to demographic characteristics, causes of transplantation, conditions that may lead to infection, postoperative infections, pathogens, and resistance patterns.

RESULTS

Of the 107 patients who underwent liver transplantation, 48 (44.8%) had an infection. Bacterial infections were detected in 41% of the patients, and fungal infections were found in 13%. When we compared living and cadaveric transplants in terms of infection development, these rates were found to be 53% and 33%, respectively (p=0.034). No statistically significant results could be obtained when evaluating conditions such as sex, presence of underlying primary disease, Model for End-Stage Liver Disease MELD score, diabetes status, total parenteral nutrition, and risk factors for infection.

CONCLUSION

After liver transplantation, infections are often seen in the first month of the postoperative period. Knowing the most common pathogens and resistance states in this process reduces infection-related deaths by providing appropriate treatment regimens at the right time.

Outcomes of Liver Resections after Liver Transplantation at a High-Volume Hepatobiliary Center

Although more than one million liver transplantations have been carried out worldwide, the literature on liver resections in transplanted livers is scarce. We herein report a total number of fourteen patients, who underwent liver resection after liver transplantation (LT) between September 2004 and 2017. Hepatocellular carcinomas and biliary tree pathologies were the predominant indications for liver resection (n = 5 each); other indications were abscesses (n = 2), post-transplant lymphoproliferative disease (n = 1) and one benign tumor. Liver resection was performed at a median of 120 months (interquartile range (IQR): 56.5-199.25) after LT with a preoperative Model for End-Stage Liver Disease (MELD) score of 11 (IQR: 6.75-21). Severe complications greater than Clavien-Dindo Grade III occurred in 5 out of 14 patients (36%). We compared liver resection patients, who had a treatment option of retransplantation (ReLT), with actual ReLTs (excluding early graft failure or rejection, n = 44). Bearing in mind that late ReLT was carried out at a median of 117 months after first transplantation and a median of MELD of 32 (IQR: 17.5-37); three-year survival following liver resection after LT was similar to late ReLT (50.0% vs. 59.1%; p = 0.733). Compared to ReLT, liver resection after LT is a rare surgical procedure with significantly shorter hospital (mean 25, IQR: 8.75-49; p = 0.034) and ICU stays (mean 2, IQR: 1-8; p < 0.001), acceptable complications and survival rates.

Definition, reasons, and risk factors for mortality of patients listed for liver transplantation - a single-center study

BACKGROUND

 In Germany, following the principle "sickest first", patients awaiting liver transplantation (LTPL) are often transplanted with high MELD score and run the risk that they can no longer be transplanted, getting "too sick for transplant".

METHODS

 In a retrospective single-center study, we analyzed the mortality of adult patients on the waiting list for LTPL during the years 2014 to 2017. To stratify risk factors, we compared characteristics of deceased and transplanted patients.

RESULTS

 The main reasons for mortality were sepsis (42.9 %), malignancy (24.3 %) and bleeding (10.0 %). Risk factors for mortality (OR, univariate logistic regression, p < 0.05) were acute on chronic liver failure (ACLF), loss of E-MELD, sepsis, pneumonia, proof of pathogens, candidemia, stay at ICU, multiple organ failure and mechanical ventilation. Multivariate analysis revealed pneumonia (p < 0.001) and high MELD (p = 0.031) as risk factors. Transplantation was more likely in patients with E-MELD. We suggest a Waiting List Mortality Index for Transplantation (WMIT), by dividing deceased patients to transplanted patients to assess mortality. Average WMIT in our cohort was 0.65.

CONCLUSIONS

 Mortality on the waiting list is mainly determined by pneumonia and infections in high-MELD patients. Therefore, patients with ACLF after infections should be prioritized for LTPL. A WMIT might suitably represent waiting list mortality.

Current Challenges in the Post-Transplant Care of Liver Transplant Recipients in Germany

Improving long-term patient and graft survival after liver transplantation (LT) remains a major challenge. Compared to the early phase after LT, long-term morbidity and mortality of the recipients not only depends on complications immediately related to the graft function, infections, or rejection, but also on medical factors such as de novo malignancies, metabolic disorders (e.g., new-onset diabetes, osteoporosis), psychiatric conditions (e.g., anxiety, depression), renal failure, and cardiovascular diseases. While a comprehensive post-transplant care at the LT center and the connected regional networks may improve outcome, there is currently no generally accepted standard to the post-transplant management of LT recipients in Germany. We therefore described the structure and standards of post-LT care by conducting a survey at 12 German LT centers including transplant hepatologists and surgeons. Aftercare structures and form of cost reimbursement considerably varied between LT centers across Germany. Further discussions and studies are required to define optimal structure and content of post-LT care systems, aiming at improving the long-term outcomes of LT recipients.

Patterns and predictors of mortality and disease progression among patients with non-alcoholic fatty liver disease

BACKGROUND

Factors associated with mortality and disease progression in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are poorly understood.

AIMS

To assess the impact of liver disease severity, demographics and comorbidities on all-cause mortality and liver disease progression in a large, real-world cohort of NAFLD patients.

METHODS

Claims data from the German Institut für angewandte Gesundheitsforschung database between 2011 and 2016 were analyzed retrospectively. Adult patients diagnosed with NAFLD and/or NASH were categorised as NAFLD, NAFLD non-progressors, compensated cirrhosis, decompensated cirrhosis, liver transplant or hepatocellular carcinoma (HCC). The longitudinal probability of mortality and incidence of progression were calculated for disease severity cohorts and multivariable analyses performed for adjusted mortality.

RESULTS

Among 4 580 434 patients in the database, prevalence of NAFLD was 4.7% (n = 215 655). Of those, 36.8% were non-progressors, 0.2% compensated cirrhosis, 9.6% decompensated cirrhosis, 0.0005% liver transplant and 0.2% HCC. Comorbidity rates were significantly higher in compensated cirrhosis, decompensated cirrhosis and HCC compared with non-progressors. The longitudinal probability of mortality for non-progressors, compensated cirrhosis, decompensated cirrhosis and HCC was 3.6%, 18.7%, 28.8% and 68%, respectively. Independent predictors of mortality included cardiovascular disease, type 2 diabetes mellitus, hypertension, obesity and renal impairment. The cumulative incidence of progression in NAFLD and compensated cirrhosis patients was 10.7% and 16.7%, respectively, over 5 years of follow-up.

CONCLUSION

NAFLD patients were severely under-diagnosed and had a high probability of mortality that increased with disease progression. Early identification and effective management to halt or reverse fibrosis are essential to prevent progression.

Adenosine A2a Receptor Stimulation Attenuates Ischemia-Reperfusion Injury and Improves Survival in A Porcine Model of DCD Liver Transplantation

Orthotopic liver transplantation (OLT) using allografts from donation after circulatory death (DCD) is potentially associated with compromised clinical outcomes due to ischemia-reperfusion injury (IRI)-induced organ damage and graft-related complications. The aim of this study was to provide in vivo data on the effects of adenosine A2a receptor stimulation in a clinically relevant large animal model of DCD liver transplantation. Cardiac arrest was induced in German Landrace pigs (n = 10; 20-25 kg). After 30 min of warm ischemia, the donor liver was retrieved following a cold flush with 3 L of histidine-tryptophan-ketoglutarate-HTK solution. Animals of the treatment group (n = 5/group) received a standard dose of the selective adenosine receptor agonist CGS 21680 added to the cold flush. All grafts were stored for 4.5 h at 4 °C in HTK-solution before OLT. Hepatocellular injury, apoptosis, protein kinase A-PKA activity, graft microcirculation, liver function, and animal survival were assessed. Compared to untreated livers, adenosine A2a receptor stimulation resulted in improved tissue microcirculation (103% ± 5% vs. 38% ± 4% compared to baseline; p < 0.05), accelerated functional recovery of the graft (indocyanine green-plasma disappearance rate (ICG-PDR) of 75% ± 18% vs. 40% ± 30% after 3 h), increased PKA activity ratio (56% ± 3% vs. 32% ± 3%; p < 0.001 after 1 h), and consequently reduced tissue necrosis and apoptosis. The potent protective effects were clinically manifested in significantly improved survival in the treatment group after 72 h (100% vs. 40%; p = 0.04). The ex vivo administration of adenosine A2a receptor agonist during the back-table flush mitigates IRI-mediated tissue damage and improves functional graft recovery and survival in a large animal model of DCD liver transplantation.

Challenges of LC-MS/MS ethyl glucuronide analysis in abstinence monitoring of liver transplant candidates

Background Urinary ethyl glucuronide (EtG) has emerged as the biomarker of choice for alcohol abstinence monitoring in forensic toxicology and is now used in the listing decision process for liver transplantations (LTs) in the German transplant program. However, EtG analysis in this patient group is challenging due to severely impaired liver function, renal failure, co-morbidities and multidrug regimens. The aim of our study was to evaluate liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based EtG analysis for a precise abstinence monitoring in transplant candidates. Methods EtG and ethyl sulfate (EtS) were analyzed by a commercial LC-MS/MS assay in 1787 spot urine samples of 807 patients (>85% from the Department of Hepatology) using a combination of quantifier and two qualifier mass transitions for each analyte. Influences of bacterial contamination, kidney and liver function were investigated. Results Two hundred and sixty-four urine samples had elevated (≥0.5 mg/L) EtG concentrations when only analyzing one quantifier mass transition. Eleven results (4.2%) were found to be false positive after combining three mass transitions for EtG quantification and verification with parallel analysis of EtS. Decreased kidney function was associated with a significantly higher rate of positive EtG samples. One of the false positive results was caused by bacterial metabolism. Conclusions Multimorbid pre-transplant patients have a high risk of individual analytical disturbances of EtG results obtained by LC-MS/MS. Therefore, EtG and EtS should always be measured by a combination of one quantifier and two qualifiers each and evaluated together.

[Hepatic dysfunction in sepsis]

Sepsis represents a life-threatening condition that frequently accompanies acute hepatic dysfunction. As a result of systemic inflammation, immune dysregulation, and microcirculatory derangements, different types of liver dysfunction can occur, such as hypoxic hepatitis, sepsis-associated cholestasis, or liver failure. A very serious and late sequela is secondary sclerosing cholangitis of the critically ill patient. Clinical management of sepsis-related liver dysfunction includes the rapid identification and treatment of the suspected underlying infection, hemodynamic stabilization to improve hepatic perfusion, and the optimization of oxygen delivery to the liver. Despite maximum efforts in supportive treatment, the outcome of patients with sepsis or septic shock and concomitant severe hepatic dysfunction remains very poor.

Early outcomes of implanting larger-sized grafts in deceased donor liver transplantation

BACKGROUND

The outcomes of large-sized graft mismatch in deceased donor liver transplantation (LT) have been rarely studied. The aim of this study was to determine whether a large-sized graft for recipient influenced the post-transplant outcomes.

METHODS

A total of 273 patients undergoing LT were enrolled and divided into a large and a normal-sized graft group by graft weight to recipient weight (GWRW) >2.5% (n = 76) or GWRW ≤2.5% (n = 197). Post-operative complications and outcomes were retrospectively analysed.

RESULTS

The two groups were comparable in demographic characteristics. The rate of complications was significantly higher in the large-sized graft group including early allograft dysfunction (36.8% versus 17.8%, P = 0.001), hepatic necrosis (26.3% versus 13.7%, P = 0.01) and massive hydrothorax (25% versus 14.7%, P = 0.04). The large-sized graft group suffered higher early mortality compared with the normal-sized graft group (30 days: 14.5% versus 5.6%, P = 0.02, 90 days: 21.1% versus 9.6%, P = 0.01). The primary causes of early death were multiple organ failure (10.5% versus 2%, P = 0.002) and sepsis (2.6% versus 1.5%, P = 0.54). Four parameters including donor alanine transaminase, GWRW, estimated blood loss and model for end-stage liver disease score were significant on multivariate analysis, and indicated significant risk factors for the early mortality of recipients.

CONCLUSION

In deceased donor LT, GWRW >2.5% is associated with increased liver injury, risk of early mortality and other adverse outcomes. Thus, donor livers should be allocated to recipients with GWRW ≤2.5%.

Effect of COVID-19 on liver transplantation in Korea

COVID-19 is now a pandemic with increasing numbers of cases and deaths. In addition to the economic and social damage caused by COVID-19 outbreak prolongation, damage caused by delayed treatment of other diseases such as severe cirrhosis is also serious. We aimed to describe the effect of COVID-19 on the number of liver transplants (LT) in South Korea. The number of LT performed in Korea during the Middle East Respiratory Syndrome (MERS) outbreak, and the COVID-19 pandemic was compared with the average number of LT performed in the past 5 years. There were 108.5 cases of LT performed per month during the MERS outbreak. It was 11% lower than the average of 122.8 cases per month for the last 5 years. LDLT and DDLT decreased by 13% to 75.3 cases and by 7.5% to 33.2 cases per month during the MERS epidemic, respectively. From January to March 2020 (COVID-19 outbreak), the number of LT did not decrease significantly. The lockdown caused by COVID-19 did not affect the number of liver transplants in Korea. Establishing a safe process and procedure of liver transplantation within safe boundaries can be beneficial in reducing the side effects of lockdown and saving patients' lives.

The Effects of MELD-Based Liver Allocation on Patient Survival and Waiting List Mortality in a Country with a Low Donation Rate

The Model for End-Stage Liver Disease (MELD)-based allocation system was implemented in Germany in 2006 in order to reduce waiting list mortality. The purpose of this study was to evaluate post-transplant results and waiting list mortality since the introduction of MELD-based allocation in our center and in Germany. Adult liver transplantation at the Charité—Universitätsmedizin Berlin was assessed retrospectively between 2005 and 2012. In addition, open access data from Eurotransplant (ET) and the German Organ Transplantation Foundation (DSO) were evaluated. In our department, 861 liver transplantations were performed from 2005 to 2012. The mean MELD score calculated with the laboratory values last transmitted to ET before organ offer (labMELD) at time of transplantation increased to 20.1 from 15.8 (Pearson’s R = 0.121, p < 0.001, confidence interval (CI) = 0.053–0.187). Simultaneously, the number of transplantations per year decreased from 139 in 2005 to 68 in 2012. In order to overcome this organ shortage the relative number of utilized liver donors in Germany has increased (85% versus 75% in non-German ET countries). Concomitantly, 5-year patient survival decreased from 79.9% in 2005 to 60.3% in 2012 (p = 0.048). At the same time, the ratio of waiting list mortality vs. active-listed patients nearly doubled in Germany (Spearman’s rho = 0.903, p < 0.001, CI = 0.634–0.977). In low-donation areas, MELD-based liver allocation may require reconsideration and inclusion of prognostic outcome factors.

Increased Cell-Free DNA Plasma Concentration Following Liver Transplantation Is Linked to Portal Hepatitis and Inferior Survival

Donor organ quality is crucial for transplant survival and long-term survival of patients after liver transplantation. Besides bacterial and viral infections, endogenous damage-associated molecular patterns (DAMPs) can stimulate immune responses. Cell-free DNA (cfDNA) is one such DAMP that exhibits highly proinflammatory effects via DNA sensors. Herein, we measured cfDNA after liver transplantation and found elevated levels when organs from resuscitated donors were transplanted. High levels of cfDNA were associated with high C-reactive protein, leukocytosis as well as granulocytosis in the recipient. In addition to increased systemic immune responses, portal hepatitis was observed, which was associated with increased interface activity and a higher numbers of infiltrating neutrophils and eosinophils in the graft. In fact, the cfDNA was an independent significant factor in multivariate analysis and increased concentration of cfDNA was associated with inferior 1-year survival. Moreover, cfDNA levels were found to be decreased significantly during the postoperative course when patients underwent continuous veno-venous haemofiltration. In conclusion, patients receiving livers from resuscitated donors were characterised by high postoperative cfDNA levels. Those patients showed pronounced portal hepatitis and systemic inflammatory responses in the short term leading to a high mortality. Further studies are needed to evaluate the clinical relevance of cfDNA clearance by haemoadsorption and haemofiltration in vitro and in vivo.

Ischemia-Reperfusion Injury in Marginal Liver Grafts and the Role of Hypothermic Machine Perfusion: Molecular Mechanisms and Clinical Implications

Ischemia-reperfusion injury (IRI) constitutes a significant source of morbidity and mortality after orthotopic liver transplantation (OLT). The allograft is metabolically impaired during warm and cold ischemia and is further damaged by a paradox reperfusion injury after revascularization and reoxygenation. Short-term and long-term complications including post-reperfusion syndrome, delayed graft function, and immune activation have been associated with IRI. Due to the current critical organ shortage, extended criteria grafts are increasingly considered for transplantation, however, with an elevated risk to develop significant features of IRI. In recent years, ex vivo machine perfusion (MP) of the donor liver has witnessed significant advancements. Here, we describe the concept of hypothermic (oxygenated) machine perfusion (HMP/HOPE) approaches and highlight which allografts may benefit from this technology. This review also summarizes clinical applications and the main aspects of ongoing randomized controlled trials on hypothermic perfusion. The mechanistic aspects of IRI and hypothermic MP-which include tissue energy replenishment, optimization of mitochondrial function, and the reduction of oxidative and inflammatory damage following reperfusion-will be comprehensively discussed within the context of current preclinical and clinical evidence. Finally, we highlight novel trends and future perspectives in the field of hypothermic MP in the context of recent findings of basic and translational research.

[High donor age for liver transplantation : Tackling organ scarcity in Germany]

BACKGROUND

Liver transplantation is the only curative treatment option for patients with end-stage liver disease; however, the 40% decline of available organ donors in recent years in Germany necessitates the optimization of available resources and possibly extending the criteria to older donors.

MATERIAL AND METHODS

All 2652 livers made available to the Charité Universitätsmedizin Berlin from 2010 to 2016 were retrospectively analyzed and the clinical outcome of 526 liver transplantations during this time frame were evaluated.

RESULTS

The median age of donors of transplanted organs increased from 49.3 years in 2010 to 57.3 years in 2016 (p = 0.02). Organs from donors ≥65 years were more frequently discarded than organs from younger donors (n = 344, 18.4% vs. n = 220, 28.1%; p = 0.005). Moreover, the older donors had higher rates of diabetes mellitus and hepatic steatosis. Organs from older donors had a higher donor risk index (2.8 vs. 2.2; p < 0.001) and were transplanted more often in patients with preserved liver function and hepatocellular carcinoma and liver cirrhosis (n = 121, 74.7% of indications). The 3‑year survival after liver transplantation from donors ≥65 and ≥80 years old was not significantly reduced in comparison to younger donors; however, there was an increased retransplantation rate (28.6%; p = 0.005) after transplantation of organs from donors ≥80 years old.

CONCLUSION

Despite conservative organ acceptance there were higher rates of retransplantation after transplantation from very old donors. In the light of an increasing scarcity of suitable organs this mandates caution and highlights the need for adequate assessment instruments for marginal donor organs before transplantation.

[Hepatic dysfunction in patients with cardiogenic shock]

Cardiogenic shock is a life-threatening condition that is frequently associated with acute hepatic dysfunction. Due to low cardiac output resulting in end-organ hypoperfusion and hypoxia, different types of liver dysfunction can develop, such as hypoxic hepatitis or acute liver failure. A very serious and late sequela is the secondary sclerosing cholangitis in critically patients. Clinical management of acute hepatic dysfunction involves the stabilization of cardiac output to improve hepatic perfusion and the optimization of liver oxygenation. However, despite maximum efforts in supportive treatment, the outcome of patients with cardiogenic shock and concomitant hepatic dysfunction remains poor.

[Treatment of hepatocellular carcinoma in the cirrhotic and non-cirrhotic liver]

BACKGROUND AND OBJECTIVES

The treatment of hepatocellular carcinoma (HCC) includes surgical, interventional and systemic approaches. This review highlights the importance of surgical treatment approaches in the multimodal treatment of HCC, based on the currently available literature, corresponding German guidelines as well as current developments in organ donation in Germany.

RESULTS

Curative treatment options for HCC include liver transplantation, partial liver resection, and local ablative procedures depending on the lesion size. In the case of an early HCC in a cirrhotic liver fulfilling the Milan criteria, liver transplantation is the treatment of choice. In view of the organ shortage in Germany and improved results after partial liver resection, surgery can alternatively be performed in patients with a sufficient liver function. In selected patients with multinodular HCC, regional lymph node metastases or macrovascular invasion, the possibility of liver resection must be decided on an individual basis; however, the latter two criteria are contraindications for transplantation. Local ablative procedures can be considered as an alternative to resection in selected patients with early solitary HCC. Surgery of HCC in the non-cirrhotic liver with a curative intent is guided by the general principles of oncological liver surgery.

DISCUSSION

Curative treatment options for HCC include liver transplantation, partial liver resection and local ablative procedures. Current developments in the area of organ donation and technical advances in minimally invasive liver surgery should be included in decision-making in tumor boards.

Risk Factors for High Mortality on the Liver Transplant Waiting List in Times of Organ Shortage: A Single-Center Analysis

BACKGROUND Germany has the highest rate of patients dying or becoming unfit for transplant while waitlisted within the Eurotransplant region. Therefore, the aim of the current study was to analyze mortality as well as risk factors for mortality of candidates listed for liver transplantation at our center. MATERIAL AND METHODS Between 01/2011 and 12/2013, 481 adult patients were listed for primary liver transplantation (LT) at a single German center. Clinical and laboratory parameters were prospectively collected and retrospectively analyzed by univariable and multivariable logistic regression and Cox proportional hazards. RESULTS The mean model for end-stage liver disease (MELD) score of all liver transplant waitlist registrants (52.4 years, 60.1% male) was 16.9 (±10.2) at time of listing, with 10% of the listed patients having a MELD score of >32. After waitlisting, 133 (27.7%) candidates died within the follow-up period. Three-month-survival after listing for transplantation was 89% for patients ultimately receiving LT vs. 71.2% that did not receive LT (p<0.001). Multivariable analysis identified clinical parameters such as ICU treatment, preceding abdominal surgery, variceal bleeding, and ascites, as well as hydropic decompensation, as independent risk factors for waitlist mortality. CONCLUSIONS Consideration of independent risk factors of mortality within the MELD-based allocation system potentially improves assessment of individual urgency and might improve utilization of available organs.

Hepatic CYP1A2 activity in liver tumors and the implications for preoperative volume-function analysis

Dynamic liver function assessment by the [¹³C]methacetin maximal liver function capacity (LiMAx) test reflects the overall hepatic cytochrome P-450 (CYP) 1A2 activity. One proven strategy for preoperative risk assessment in liver surgery includes the combined assessment of the dynamic liver function by the LiMAx test, the volumetric analysis of the liver, and calculation of future liver remnant function. This so-called volume-function analysis assumes that the remaining CYP1A2 activity in any tumor lesion is zero. The here presented study aims to assess the remaining CYP1A2 activities in different hepatic tumor lesions and its consequences for the preoperative volume-function analysis in patients undergoing liver surgery. The CYP1A2 activity analysis of neoplastic lesions and adjacent nontumor liver tissue from resected tumor specimens revealed a significantly higher CYP1A2 activity (median, interquartile range) in nontumor tissues (35.5, 15.9-54.4 µU/mg) compared with hepatocellular adenomas (7.35, 1.2-32.5 µU/mg), hepatocellular carcinomas (0.18, 0.0-2.0 µU/mg), or colorectal liver metastasis (0.17, 0.0-2.1 µU/mg). In nontumor liver tissue, a gradual decline in CYP1A2 activity with exacerbating fibrosis was observed. The CYP1A2 activity differences were also reflected in CYP1A2 protein signals in the assessed hepatic tissues. Volume-function analysis showed a minimal deviation compared with the current standard calculation for hepatocellular carcinomas or colorectal liver metastasis (<1% difference), whereas a difference of 11.9% was observed for hepatocellular adenomas. These findings are important for a refined preoperative volume-function analysis and improved surgical risk assessment in hepatocellular adenoma cases with low LiMAx values. NEW & NOTEWORTHY The cytochrome P-450 (CYP) 1A2-dependent maximal liver function capacity test reflects the overall functional capacity of the liver. To which extent hepatocellular tumors harbor CYP1A2 activity and thus contribute to the maximal liver function capacity test outcome is unknown. We here show that hepatocellular adenomas but not hepatocellular carcinomas or colorectal liver metastasis contain significant residual CYP1A2 activity. These findings are important for an improved preoperative volume-function analysis and an accurate surgical risk assessment in hepatocellular adenoma cases.

Liver graft preservation methods during cold ischemia phase and normothermic machine perfusion

The growing demand for donor organs requires measures to expand donor pool. Those include extended criteria donors, such as elderly people, steatotic livers, donation after cardiac death, etc. Static cold storage to reduce metabolic requirements developed by Collins in late 1960s is the mainstay and the golden standard for donated organ protection. Hypothermic machine perfusion provides dynamic organ preservation at 4°C with protracted infusion of metabolic substrates to the graft during the ex vivo period. It has been used instead of static cold storage or after it as short perfusion in transplant center. Normothermic machine perfusion (NMP) delivers oxygen, and nutrition at physiological temperature mimicking regular environment in order to support cellular function. This would minimize effects of ischemia/reperfusion injury. Potentially, NMP may help to estimate graft functionality before implantation into a recipient. Clinical studies demonstrated at least its non-inferiority or better outcomes vs static cold storage. Regular grafts donated after brain death could be safely preserved with convenient static cold storage. Except for prolonged ischemia time where hypothermic machine perfusion started in transplant center could be estimated to provide possible positive reconditioning effect. Use of hypothermic machine perfusion in regular donation instead of static cold storage or in extended criteria donors requires further investigation. Multicenter randomized clinical trial supposed to be completed in December 2021. Extended criteria donors need additional measures for graft storage and assessment until its implantation. NMP is actively evaluating promising method for this purpose. Future studies are necessary for precise estimation and confirmation to issue clinical practice recommendations.

Treatment Strategies for Hepatocellular Carcinoma ⁻ a Multidisciplinary Approach

Hepatocellular carcinoma (HCC) is the most common primary tumor of the liver and its mortality is third among all solid tumors, behind carcinomas of the lung and the colon. Despite continuous advancements in the management of this disease, the prognosis for HCC remains inferior compared to other tumor entities. While orthotopic liver transplantation (OLT) and surgical resection are the only two curative treatment options, OLT remains the best treatment strategy as it not only removes the tumor but cures the underlying liver disease. As the applicability of OLT is nowadays limited by organ shortage, major liver resections—even in patients with underlying chronic liver disease—are adopted increasingly into clinical practice. Against the background of the oftentimes present chronical liver disease, locoregional therapies have also gained increasing significance. These strategies range from radiofrequency ablation and trans-arterial chemoembolization to selective internal radiation therapy and are employed in both curative and palliative intent, individually, as a bridging to transplant or in combination with liver resection. The choice of the appropriate treatment, or combination of treatments, should consider the tumor stage, the function of the remaining liver parenchyma, the future liver remnant volume and the patient’s general condition. This review aims to address the topic of multimodal treatment strategies in HCC, highlighting a multidisciplinary treatment approach to further improve outcome in these patients.

Accuracy of Pretransplant Imaging Diagnostic for Hepatocellular Carcinoma: A Retrospective German Multicenter Study

Selection and prioritization of patients with HCC for LT are based on pretransplant imaging diagnostic, taking the risk of incorrect diagnosis. According to the German waitlist guidelines, imaging has to be reported to the allocation organization (Eurotransplant) and pathology reports have to be submitted thereafter. In order to assess current procedures we performed a retrospective multicenter analysis in all German transplant centers with focus on accuracy of imaging diagnostic and tumor classification. 1168 primary LT for HCC were conducted between 2007 and 2013 in Germany. Patients inside the Milan, UCSF, and up-to-seven criteria were misclassified with definitive histologic results in 18%, 15%, and 11%, respectively. Patients pretransplant outside the Milan, UCSF, and up-to-seven criteria were otherwise misclassified in 34%, 43%, and 41%. Recurrence-free survival correlated with classification by posttransplant histological report, but not pretransplant imaging diagnostic. Univariate analysis revealed tumor size, vascular invasion, and grading as significant parameters for outcome, while tumor grading was the only parameter persisting by multivariate testing. Conclusion. There was a relevant percentage (15-40%) of patients misclassified by imaging diagnosis at a time prior to LI-RADS and guidelines to improve imaging of HCC. Outcome analysis showed a good correlation to histological, in contrast poor correlation to imaging diagnosis, suggesting an adjustment of the LT selection and prioritization criteria.