Liver transplantation: current and future

Prognostic value of angiogenic T cells in hepatitis B-induced liver cirrhosis

This study was performed to investigate the frequency of angiogenic T cells (CD4+ Tang cells) among CD4+ T cells in patients with hepatitis B-induced liver cirrhosis (HBV-LC) and to evaluate the predictive role of these cells in the clinical outcome. In total, 185 patients with HBV-LC were recruited to measure the frequency of CD4+ Tang cells and chemokine levels using flow cytometry. RESULTS: There was 11.4% of death after 3-momth follow-up. The AUC for the ability of the frequency of CD4+ Tang cell to predict death was 0.724 (higher than those for the MELD score, FIB-4 score, and Child-Pugh classification). Cox regression analysis revealed an association between the frequency of CD4+ Tang cells and a 3-month survival chance. CONCLUSIONS: The lower frequency of CD4+ T ang cells was correlated with the severity of HBV-LC and may serve as a prognostic predictor.

Effect of Donor Age and Liver Steatosis on Potential of Decellularized Liver Matrices to be used as a Platform for iPSC-Hepatocyte Culture

Decellularization of discarded whole livers and their recellularization with patient-specific induced pluripotent stem cells (iPSCs) to develop a functional organ is a promising approach to increasing the donor pool. The effect of extracellular matrix (ECM) of marginal livers on iPSC-hepatocyte differentiation and function has not been shown. To test the effect of donor liver ECM age and steatosis, young and old, as well as no, low, and high steatosis livers, are decellularized. All livers are decellularized successfully. High steatosis livers have fat remaining on the ECM after decellularization. Old donor liver ECM induces lower marker expression in early differentiation stages, compared to young liver ECM, while this difference is closed at later stages and do not affect iPSC-hepatocyte function significantly. High steatosis levels of liver ECM lead to higher albumin mRNA expression and secretion while at later stages of differentiation expression of major cytochrome (CYP) 450 enzymes is highest in low steatosis liver ECM. Both primary human hepatocytes and iPSC-hepatocytes show an increase in fat metabolism marker expression with increasing steatosis levels most likely induced by excess fat remaining on the ECM. Overall, removal of excess fat from liver ECM may be needed for inducing proper hepatic function after recellularization.

Post Liver Transplant Renal Dysfunction-Evaluation, Management and Immunosuppressive Practice

Liver transplantation (LT) is an effective and lifesaving treatment for patients with end-stage liver disease and hepatocellular carcinoma. Significant improvement in intermediate and long-term survival has been possible due to advancements in immunosuppressive therapy, perioperative care, and surgical techniques. Despite these advances, metabolic complications, including diabetes mellitus, cardiovascular diseases, malignancies, and renal dysfunction, are challenging issues after LT. Acute kidney injury (AKI) and chronic kidney disease (CKD) after LT are common and result in significant morbidity and mortality. Early diagnosis of kidney injury after LT is challenging, and no technique has yet proven effective in prediction of renal dysfunction. The methods for assessing renal function range from formulas that predict glomerular filtration rate to non-invasive biomarkers. The universal adoption of the model for end-stage liver disease has a direct impact on the incidence of peri-transplant AKI and development of CKD in the long-term. Post-LT renal dysfunction is multifactorial and is usually a result of pre-transplantation comorbidities, occurrence of renal dysfunction on the waiting list, perioperative events, and post-transplant nephrotoxic immunosuppressive medication use. Early identification of patients at risk for renal dysfunction and adoption of preventive measures are crucial in the pre-transplant period. No data are currently available to suggest a surgical technique that reliably demonstrates renal protection. Nephroprotective strategies during LT follow accepted surgical practice guidelines, such as maintenance of intravascular volume and mean arterial pressure. The management of kidney disease following LT is challenging, as by the time the serum creatinine is significantly elevated, few interventions impact the course of progression. Early nephroprotective measures are strongly advised and they mostly center on delaying the administration of calcineurin inhibitors (CNIs) during the initial postoperative period, lowering CNI dosage and combining CNI with mycophenolate mofetil and everolimus. The reasons for renal failure following LT, the techniques used to diagnose it, and the therapies designed to preserve renal function both immediately and late after LT are all critically evaluated in this review.

The Predictive Value of Graft Viability and Bioenergetics Testing Towards the Outcome in Liver Transplantation

Donor organ biomarkers with sufficient predictive value in liver transplantation (LT) are lacking. We herein evaluate liver viability and mitochondrial bioenergetics for their predictive capacity towards the outcome in LT. We enrolled 43 consecutive patients undergoing LT. Liver biopsy samples taken upon arrival after static cold storage were assessed by histology, real-time confocal imaging analysis (RTCA), and high-resolution respirometry (HRR) for mitochondrial respiration of tissue homogenates. Early allograft dysfunction (EAD) served as primary endpoint. HRR data were analysed with a focus on the efficacy of ATP production or P-L control efficiency, calculated as 1-L/P from the capacity of oxidative phosphorylation P and non-phosphorylating respiration L. Twenty-two recipients experienced EAD. Pre-transplant histology was not predictive of EAD. The mean RTCA score was significantly lower in the EAD cohort (-0.75 ± 2.27) compared to the IF cohort (0.70 ± 2.08; p = 0.01), indicating decreased cell viability. P-L control efficiency was predictive of EAD (0.76 ± 0.06 in IF vs. 0.70 ± 0.08 in EAD-livers; p = 0.02) and correlated with the RTCA score. Both RTCA and P-L control efficiency in biopsy samples taken during cold storage have predictive capacity towards the outcome in LT. Therefore, RTCA and HRR should be considered for risk stratification, viability assessment, and bioenergetic testing in liver transplantation.

Transient growth factor expression via mRNA in lipid nanoparticles promotes hepatocyte cell therapy to treat murine liver diseases

Primary human hepatocyte (PHH) transplantation is a promising alternative to liver transplantation, whereby liver function could be restored by partial repopulation of the diseased organ with healthy cells. However, currently PHH engraftment efficiency is low and benefits are not maintained long-term. Here we refine two mouse models of human chronic and acute liver diseases to recapitulate compromised hepatocyte proliferation observed in nearly all human liver diseases by overexpression of p21 in hepatocytes. In these clinically relevant contexts, we demonstrate that transient, yet robust expression of human hepatocyte growth factor and epidermal growth factor in the liver via nucleoside-modified mRNA in lipid nanoparticles, whose safety was validated with mRNA-based COVID-19 vaccines, drastically improves PHH engraftment, reduces disease burden, and improves overall liver function. This novel strategy may overcome the critical barriers to clinical translation of cell therapies with primary or stem cell-derived hepatocytes for the treatment of liver diseases.

Preliminary study of donor volume changes after dual-graft liver transplantation in rats

Dual-graft liver transplantation (DGLT) expands the pool of donors, ensures the safety of the donors, and treats a potential small for size syndrome (SFSS). However, some of the recipient graft showed atrophy. The cause and mechanism of the unbalanced proliferation and atrophy of dual grafts after clinical DGLT have not been clarified. We established and optimized the rat model of DGLT to explore the causes of growth unbalance. Continuously and dynamically observed bilateral graft volume and portal vein blood flow change by magnetic resonance imaging (MRI) and ultrasound (US). We detected liver function indexes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total bilirubin (TBIL), direct bilirubin (DBIL), and indirect bilirubin (IBIL). Liver samples from receptors were obtained for morphology, and apoptosis was measured by RT-PCR and western blot. Optimization of the model improved the 7-day survival rate from former 58.3% to 87.5%, and the 30-day survival rate was 68.8%. The volume of the right graft gradually increased, and the left graft atrophied during the 30-day observation period. The portal blood flow of the left graft gradually decreased until the 30th day (0.13 ± 0.01 ml/s) compared with the sham group (0.63 ± 0.05 ml/s), and the right graft significantly increased on the 30th day (0.75 ± 0.11ml/s). The liver function initially increased and then recovered. The total volume (12.52 ± 1.60 ml vs 4.47 ± 0.08 ml) and weight (12.09 ± 1 g vs 4.91 ± 0.18 g) of the graft increased significantly compared to pre-transplantation and reached the level of the sham operation group on the 30th day. The volume and weight of the right graft increased more than those of the left graft (P < 0.05). There was more inflammatory cell infiltration in the left graft, and the right graft had obvious proliferation of hepatocytes and mature bile duct cells. Left grafts were more prone to apoptosis than right grafts (P < 0.05). In conclusion, growth of the right graft is superior to the left; after double liver transplantation, perfusion blood flow and apoptosis may be the reason contributing to the volume differences in dual grafts.

Emergency Department Frequentation and Unscheduled Visits of Liver Transplant Patients: Ten Years Experience in Tertiary Care Center, Saudi Arabia

Introduction and objectives Liver transplantation and its indications represent an increased burden on patients' health. This can be represented in a variety of ways, such as in emergency visits, unscheduled clinic visits, and unanticipated admissions. This study aims to analyze emergency department (ED) visits, the most common presenting complaints, and the outcomes of those visits. Methods A retrospective observational study was performed in which electronic medical records were reviewed for all patients who underwent liver transplantation and presented to the emergency department between October 2011 and October 2021. The following data were collected: demographics, comorbidities, liver transplant features, and emergency department visit data and outcomes. Recurrent visits were assessed and labeled as first, second, third, fourth, and fifth or more. Results A total of 699 patients and 5,225 visits were included in the analysis. Living donors accounted for 80% of all transplants. The mean post-operative length of stay was 22.6 ± 17.8. The majority of patients (74%) had at least one comorbidity, with diabetes (47%), hypertension (31%), and chronic kidney disease (CKD) (16%) being the commonest comorbidities; however, comorbidities were not associated with an increased risk of emergency department visits. Out of the 5,225 visits to the emergency department, 2,265 (41%) were within the first year. Emergency department visits in the first seven days after discharge amounted to 22% of total first visits. By 30 days, six months, and one year, they increased to 46%, 83%, and 91%, respectively. Living donor recipients had an average of 7.3 ED visits as compared to deceased donor recipients, who had an average of 8.4 ED visits. The most common presenting complaints were gastrointestinal (GI) symptoms (18%), infectious disease symptoms (9%), and respiratory symptoms (8%). There were a total of 296 patients who were readmitted at least once since discharge after liver transplantation. Conclusion The majority of first-time presentations to ED occurred in the first year post-transplant, marking this time period as critical for liver transplant patients. Our study also highlighted the continual presentations of liver transplant patients to the ED a few years post-transplant. This requires close scrutiny of the main causes of such presentations as well as comparison with other transplant cases to identify whether they are specific to liver transplants or not.

A simple and efficient strategy for cell-based and cell-free-based therapies in acute liver failure: hUCMSCs bioartificial liver

Acute liver failure (ALF) is a life-threatening condition. Cell-based and cell-free-based therapies have proven to be effective in treating ALF; however, their clinical application is limited by cell tumorigenicity and extracellular vesicle (EV) isolation in large doses. Here, we explored the effectiveness and mechanism of umbilical cord mesenchymal stem cells (hUCMSCs)-based bioartificial liver (hUCMSC-BAL), which is a simple and efficient strategy for ALF. D-galactosamine-based pig and mouse ALF models were used to explore the effectiveness of hUCMSC-BAL and hUCMSC-sEV therapies. Furthermore, high-throughput sequencing, miRNA transcriptome analysis, and western blot were performed to clarify whether the miR-139-5p/PDE4D axis plays a critical role in the ALF model in vivo and in vitro. hUCMSC-BAL significantly reduced inflammatory responses and cell apoptosis. hUCMSC-sEV significantly improved liver function in ALF mice and enhanced the regeneration of liver cells. Furthermore, hUCMSC-sEV miRNA transcriptome analysis showed that miR-139-5p had the highest expression and that PDE4D was one of its main target genes. The sEV miR-139-5p/PDE4D axis played a role in the treatment of ALF by inhibiting cell apoptosis. Our data indicate that hUCMSC-BAL can inhibit cytokine storms and cell apoptosis through the sEV miR-139-5p/PDE4D axis. Therefore, we propose hUCMSC-BAL as a therapeutic strategy for patients with early ALF.

Application of enhanced recovery after surgery following liver transplantation

OBJECTIVE

To investigate the effect of an enhanced recovery after surgery (ERAS) programme following liver transplantation and to further clarify the safety and clinical application value of an ERAS programme.

METHODS

A retrospective analysis of 250 patients who underwent liver transplant at Beijing You'an Hospital affiliated to Capital Medical University between March 2019 and December 2021 was conducted. According to different perioperative management methods, patients were divided into a control group (120 cases) and an ERAS group (130 cases). Postoperative safety indicators, efficacy indicators and economic indicators were compared between the two groups.

RESULTS

There was no significant difference in the safety indicators between the two groups. The ERAS group showed significantly lower results compared with the control group in terms of ventilator-associated pneumonia, urinary tract infection, pressure injury of oral and nasal mucosa, postoperative pain score 5 days after surgery and the incidence of delirium, whereas the Barthel score 10 days after surgery was significantly higher. There was no significant difference between the two groups in skin pressure injury or the Subjective Global Assessment grade 10 days after surgery. The length of intensive care unit stay, the total length of stay after surgery and the 10-day medical expenses after surgery were significantly lower in the ERAS group than in the control group.

CONCLUSION

The application of an ERAS programme after liver transplantation can effectively promote the postoperative recovery of patients and reduce medical costs. Studies have shown that the ERAS programme has important application value in improving the postoperative quality of life and reducing the economic burden of patients after liver transplantation. This programme provides a new concept for related clinical improvement and application.

Impact of Sirolimus versus Mycophenolate Mofetil on Kidney Function after Calcineurin Inhibitor Dose Reduction in Liver Transplant Recipients

Impaired kidney function is associated with increased morbidity and mortality in patients undergoing liver transplantation. Although immunosuppressants are essential in these patients, they impair kidney function. This study aimed to compare adverse kidney outcomes between patients treated with a reduced dose of tacrolimus (calcineurin inhibitor) plus sirolimus or mycophenolate mofetil (MMF) in the liver transplant center at Kaohsiung Chang Gung Memorial Hospital between April 2011 and December 2017. Propensity score matching was used to identify 232 patients. The risk of adverse kidney outcomes was estimated using Cox proportional hazards regression, and changes in kidney function over time were analyzed using linear mixed modeling. Acute kidney disease risks in this study cohort were not significantly different for the two immunosuppressants (aHR 1.04; 95% CI: 0.70-1.55, p = 0.8328). However, sirolimus use was significantly associated with a higher risk of estimated glomerular filtration rate decline > 30% than MMF (aHR, 2.09; 95% CI: 1.33-3.28; p = 0.0014). Our results demonstrate that sirolimus use may have worsened long-term kidney outcomes compared to MMF. Close monitoring of kidney function, dose adjustment, and timely transition to MMF is necessary for LT patients receiving sirolimus.

The dual role dilemma of liver transplantation health care professionals

BACKGROUND

Similar to many other countries, in Germany patients with alcohol-related liver disease are obliged to prove their abstinence before being accepted on a waitlist for liver transplantation. Health care professionals (HCPs) must both treat patients and ensure that patients have proven their abstinence. The aim of this exploratory study was to develop a deeper understanding of how HCPs deal with this dual role.

METHODS

The study used semi-structured interviews as the source of data. 11 healthcare professionals from ten of the 22 German transplant centers were interviewed. After transcription, a qualitative content analysis was performed.

RESULTS

We found that these HCPs faced an ethical dilemma, as they must balance the roles of being both a treatment provider (the therapist role) and an assessor (the monitoring role). To solve this dilemma, the strategy seems to be a tendency for the HCPs to take on one dominant role amongst these two roles. HCPs who prefer to take on the therapist role seem to feel burdened by the 6-month abstinence rule and the obligation to monitor their patients. HCPs who prefer to take on the monitoring role tend to have negative assumptions about the patients. HCPs also reported the impression that patients perceive HCPs as more involved in monitoring and less open to the therapeutic role. From this it can be deduced that current regulations and structures lead both to stress for HCPs and to suboptimal therapy for those affected.

CONCLUSIONS

The results showed that current transplantation guidelines can have a negative impact on both patient care and the burdens on the HCPs. From our point of view, there are various changes that could be made to the current clinical practice that would help solve this dilemma. For instance, integrating other assessment criteria that are more closely adapted to the health status trajectory and psychosocial background of the individual patient would be both possible and would lead to improvements in practice.

Donor Simvastatin Treatment Is Safe and Might Improve Outcomes After Liver Transplantation: A Randomized Clinical Trial

BACKGROUND

The current curative approaches for ischemia/reperfusion injury on liver transplantation are still under debate for their safety and efficacy in patients with end-stage liver disease. We present the SIMVA statin donor treatment before Liver Transplants study.

METHODS

SIMVA statin donor treatment before Liver Transplants is a monocentric, double-blind, randomized, prospective tial aiming to compare the safety and efficacy of preoperative brain-dead donors' treatment with the intragastric administration of 80 mg of simvastatin on liver transplant recipient outcomes in a real-life setting. Primary aim was incidence of patient and graft survival at 90 and 180 d posttransplant; secondary end-points were severe complications.

RESULTS

The trial enrolled 58 adult patients (18-65 y old). The minimum follow-up was 6 mo. No patient or graft was lost at 90 or 180 d in the experimental group (n = 28), whereas patient/graft survival were 93.1% ( P = 0.016) and 89.66% ( P = 0.080) at 90 d and 86.21% ( P = 0.041) and 86.2% ( P = 0.041) at 180 d in the control group (n = 29). The percentage of patients with severe complications (Clavien-Dindo ≥IIIb) was higher in the control group, 55.2% versus 25.0% in the experimental group ( P = 0.0307). The only significant difference in liver tests was a significantly higher gamma-glutamyl transferase and alkaline phosphatase at 15 d ( P = 0.017), ( P = 0.015) in the simvastatin group.

CONCLUSIONS

Donor simvastatin treatment is safe, and may significantly improve early graft and patient survival after liver transplantation, although further research is mandatory.

[The Caring Experience of Family Caregivers for Patients of Living Donor Liver Transplantation from the Family Members]

PURPOSE

The purpose of the study was to understand the care experiences of the family of living donor liver transplantation (LDLT) patients where the donation had occurred within the family.

METHODS

Participants were eight family caregivers who cared for recipients and donors of LDLT. Data were collected through individual in-depth interviews from November, 2020 to April, 2021. Data analysis was performed through a cyclical process of data collection and analysis by applying Giorgi's phenomenological research method.

RESULTS

The five main components extracted from the experiences of the family caregivers were: "A double-edged choice to save the family", "The harsh daily life of liver transplantation care", "The yoke of double care on both shoulders", "The power to withstand the adversity of caring", and "The recovery and growth of life pursued by trusting each other".

CONCLUSION

The participants tried to do their best in their daily lives, while providing reassurance and care to the LDLT patients in the family; however, they expressed some worry and hardship while doing so. The results of this study provide a deeper understanding of the caring experience of the family caregivers, which may contribute to the development of nursing interventions that will aid these caregivers in providing care to their LDLT family members. Furthermore, the development and application of an integrated management program for LDLT patients in the family is required.

Intestinal Microbiota Participates in the Protective Effect of HO-1/BMMSCs on Liver Transplantation With Steatotic Liver Grafts in Rats

The present study aimed to explore whether heme oxygenase-1 (HO-1)-modified bone marrow mesenchymal stem cells (BMMSCs) have a protective effect on liver transplantation with steatotic liver grafts in rats, and to determine the role of the intestinal microbiota in such protection. HO-1/BMMSCs were obtained by transduction of Hmox1 gene [encoding heme oxygenase (HO-1)]-encoding adenoviruses into primary rat BMMSCs. Steatotic livers were obtained by feeding rats a high-fat diet, and a model of liver transplantation with steatotic liver grafts was established. The recipients were treated with BMMSCs, HO-1/BMMSCs, or neither, via the portal vein. Two time points were used: postoperative day 1 (POD 1) and POD 7. The results showed that under the effect of HO-1/BMMSCs, the degree of steatosis in the liver grafts was significantly reduced, and the level of liver enzymes and the levels of pro-inflammatory cytokines in plasma were reduced. The effect of HO-1/BMMSCs was better than that of pure BMMSCs in the prolongation of the rats' postoperative time. In addition, HO-1/BMMSCs promoted the recovery of recipients' intestinal structure and function, especially on POD 7. The intestinal villi returned to normal, the expression of tight junction proteins was restored, and intestinal permeability was reduced on POD 7. The intestinal bacterial of the LT group showed significantly weakened energy metabolism and overgrowth. On POD 1, the abundance of Akkermansiaceae was higher. On POD 7, the abundance of Clostridiaceae increased, the level of lipopolysaccharide increased, the intestinal mucosal barrier function was destroyed, and the levels of several invasive bacteria increased. When treated with HO-1/BMMSCs, the energy metabolism of intestinal bacteria was enhanced, and on POD 1, levels bacteria that protect the intestinal mucosa, such as Desulfovibrionaceae, increased significantly. On POD 7, the changed intestinal microbiota improved lipid metabolism and increased the levels of butyrate-producing bacteria, such as Lachnospiraceae. In conclusion, HO-1/BMMSCs have protective effects on steatotic liver grafts and the intestinal barrier function of the recipients. By improving lipid metabolism and increasing the abundance of butyrate-producing bacteria, the changed intestinal microbiota has a protective effect and prolongs the recipients' survival time.

Current aspects of renal dysfunction after liver transplantation

The development of chronic kidney disease (CKD) after liver transplantation (LT) exerts a severe effect on the survival of patients. The widespread adoption of the model for end-stage liver disease score strongly impacted CKD incidence after the procedure, as several patients are transplanted with previously deteriorated renal function. Due to its multifactorial nature, encompassing pre-transplantation conditions, perioperative events, and nephrotoxic immunosuppressor therapies, the accurate identification of patients under risk of renal disease, and the implementation of preventive approaches, are extremely important. Methods for the evaluation of renal function in this setting range from formulas that estimate the glomerular filtration rate, to non-invasive markers, although no option has yet proved efficient in early detection of kidney injury. Considering the nephrotoxicity of calcineurin inhibitors (CNI) as a factor of utmost importance after LT, early nephroprotective strategies are highly recommended. They are based mainly on delaying the application of CNI during the immediate postoperative-period, reducing their dosage, and associating them with other less nephrotoxic drugs, such as mycophenolate mofetil and everolimus. This review provides a critical assessment of the causes of renal dysfunction after LT, the methods of its evaluation, and the interventions aimed at preserving renal function early and belatedly after LT.

BTBD10 is a Prognostic Biomarker Correlated With Immune Infiltration in Hepatocellular Carcinoma

Background: BTBD10 serves as an activator of Akt family members through decreasing the protein phosphatase 2A-mediated dephosphorylation. The present study attempted to investigate the prognostic value of BTBD10 in hepatocellular carcinoma (HCC), specially, its relationship with tumor-infiltrating lymphocytes (TILs).

Methods: BTBD10 expression was evaluated in HCC using The Cancer Genome Atlas (TCGA) and Xijing Hospital database, and verified in HCC cell lines. Cox analyses were performed to analyze independent prognostic risk factors for HCC. The optimal cut-off value of BTBD10 was calculated, by which all patients were divided into two groups to compare the overall survival (OS). The signaling pathways were predicted, by which BTBD10 may affect the progression of HCC. To investigate the impact of BTBD10 on HCC immunotherapy, correlations between BTBD10 and TILs, immune checkpoints, m6A methylation-related genes and ferroptosis-related genes were assessed. The distribution of half-maximal inhibitory concentration (IC50) of diverse targeted drugs was observed based on the differential expression of BTBD10.

Results: BTBD10 expression was higher in HCC tissues and cell lines than that of normal liver tissues and cells. The patients with high expression of BTBD10 showed a worse OS, as compared to that of BTBD10 low-expressing group. Cox analyses indicated that BTBD10 was an independent prognostic risk factor for HCC. Several molecular pathways of immune responses were activated in HCC patients with high-expressing of BTBD10. Furthermore, BTBD10 expression was demonstrated to be positively correlated with tumor-infiltrating B cells, T cells, macrophages, neutrophils and dendritic cells. Meanwhile, the expression of BTBD10 was synchronized with that of several m6A methylation-related genes, ferroptosis-related genes and immune checkpoints. The IC50 scores of Sorafenib, Navitoclax, Veliparib, Luminespib, and Imatinib were found to be lower in BTBD10 high-expressing HCC group.

Conclusion: BTBD10 negatively regulates tumor immunity in HCC and exhibits adverse effect on the prognosis of HCC, which could be a potential target for immunotherapy.

Risk Factors of Invasive Fungal Infection in Recipients After Liver Transplantation: A Systematic Review and Meta-Analysis

Objectives: Invasive fungal infection (IFI) remains an important cause of mortality in liver transplantation (LT). The objective of this meta-analysis was to identify the risk factors for IFI after LT.

Methods: We searched for relevant studies published up to June 2020 from PubMed, Web of Science, Embase, and the Cochrane Library. Odds ratios (ORs) and their corresponding 95% CIs were used to identify significant differences in the risk factors. Heterogeneity between studies was evaluated by the I² test, and potential publication bias was assessed with Egger's test. The quality of included studies was evaluated with the Newcastle-Ottawa Scale (NOS).

Results: A total of 14 studies enrolling 4,284 recipients were included in the meta-analysis. Reoperation (OR = 2.18, 95% CI: 1.61–2.94), posttransplantation dialysis (OR = 2.03, 95% CI: 1.52–2.72), bacterial infection (OR = 1.81, 95% CI: 1.33–2.46), live donor (OR = 1.78, 95% CI: 1.20–2.63), retransplantation (OR = 2.45, 95% CI: 1.54–3.89), and fungal colonization (OR = 2.60, 95% CI: 1.99–3.42) were associated with the risk factors of IFI after LT.

Conclusions: Despite some risk factors that have been identified as significant factors for IFI post-LT, which may inform prevention recommendations, rigorous and well-designed studies with adequate sample sizes should be conducted to solve the limitations of this study.

Imaging Evaluation of Living Liver Donor Candidates: Techniques, Protocols, and Anatomy

The need for liver transplants is increasing because the prevalence of liver diseases and the indications for transplants are growing. In response to the shortage of grafts from deceased donors, more transplants are being performed worldwide with grafts from living donors. Radiologic evaluation is an integral component in the assessment of donor candidates to ensure their eligibility and to choose the most appropriate surgical approach. MRI is the preferred modality for evaluation of the liver parenchyma and biliary tree. In most centers, a combination of MRI and CT is used to take advantage of the higher spatial resolution of CT for evaluation of arteries. However, MRI-only assessment is feasible. In addition to assessment of the liver parenchyma for abnormalities such as steatosis, a detailed evaluation of the hepatic vascular and biliary system for pertinent anatomic variants is crucial, because these variants can affect surgical techniques and outcomes in both recipients and donors. In this pictorial article, after a brief review of the most common surgical techniques and postsurgical liver anatomy, the biliary and vascular anatomy are discussed, with specific attention paid to the variants that are pertinent to this surgical procedure. The roles of liver segmentation and volumetric assessment and current imaging techniques and protocols are also discussed. Online supplemental material is available for this article. ©RSNA, 2021.

Magnetic Resonance Imaging of Liver Transplant

MR imaging increasingly has been adopted for follow-up imaging post-liver transplantation and for diagnosis of its complications. These include vascular and biliary complications as well as post-transplant malignancies. Interpretation of postoperative MR imaging should take into account the surgical technique and expected post-transplant changes. Contrast-enhanced MR imaging has high sensitivity for identification of vascular complications. MR cholangiopancreatography on the other hand is the most accurate noninvasive method for evaluation of biliary complications.

Expanding Donor Selection and Recipient Indications for Living Donor Liver Transplantation

There is an acute shortage of deceased donor organs for liver transplantation in the United States. Nearly a third of patients either die or become too sick for transplant while on the transplant waitlist. Living donor liver transplantation (LDLT) bridges the gap between demand and supply of organs for liver transplantation. This article reviews current living donor selection criteria, and avenues for expansion of criteria with novel surgical techniques and ongoing outcomes research. Ways in which institutions can establish and expand LDLT programs using the Living Donor Champion model are discussed. Efforts to expand recipient indications for LDLT are described.

CEACAM1 and molecular signaling pathways to expand the liver transplant donor pool

Organ shortage continues to limit the lives of patients who require liver transplantation. While extending criteria for liver organs provides a needed resource, tissue damage from prolonged ischemic injury can result in early allograft dysfunction and consequent rejection. In this issue of the JCI, Nakamura et al. used a mouse transplantation model with prolonged ex vivo cold storage to explore liver graft protection. The authors found that liver grafts with absent carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) exhibited increased ischemia-reperfusion injury inflammation and decreased function in wild-type recipients. The authors went on to correlate CEACAM1 levels with postreperfusion damage in human liver transplant recipients. Notably, this study identified a potential biomarker for liver transplant donor graft quality.

[Living related liver transplantation]

Liver transplantation has become established as a standard procedure in the treatment of end-stage liver diseases. Despite intense efforts by all parties involved up to the amendment of the German Transplantation Act, the lack of suitable donor organs was still one of the limiting factors of this therapeutic procedure. One way out of this problem is to make so-called marginal organs usable, e.g. with the help of machine perfusion or by utilizing living liver donation, which are used in some countries for more than 90% of organ donations. In general, there is no difference in the indications for liver transplantation between a (partial) organ obtained by post-mortem or living donation. Before any living donation, a thorough evaluation of the donor is carried out in order to minimize postoperative morbidity as far as possible. Technically the partial liver donation is based on the oncological liver resection, while the partial liver transplantation is a further development of split liver transplantation after post-mortem liver donation. In specialized centers comparable or even better results can nowadays be achieved using living liver donation instead of post-mortem donation.