Chronic kidney disease in a murine model of non-alcoholic steatohepatitis (NASH)

Clinical studies suggest that non-alcoholic steatohepatitis (NASH) is an independent risk factor for chronic kidney disease (CKD), but causality and mechanisms linking these two major diseases are lacking. To assess whether NASH can induce CKD, we have characterized kidney function, histological features, transcriptomic and lipidomic profiles in a well-validated murine NASH model. Mice with NASH progressively developed significant podocyte foot process effacement, proteinuria, glomerulosclerosis, tubular epithelial cell injury, lipid accumulation, and interstitial fibrosis. The progression of kidney fibrosis paralleled the severity of the histologic NASH-activity score. Significantly, we confirmed the causal link between NASH and CKD by orthotopic liver transplantation, which attenuated proteinuria, kidney dysfunction, and fibrosis compared with control sham operated mice. Transcriptomic analysis of mouse kidney cortices revealed differentially expressed genes that were highly enriched in mitochondrial dysfunction, lipid metabolic process, and insulin signaling pathways in NASH-induced CKD. Lipidomic analysis of kidney cortices further revealed that phospholipids and sphingolipids were the most significantly changed lipid species. Notably, we found similar kidney histological changes in human NASH and CKD. Thus, our results confirm a causative role of NASH in the development of CKD, reveal potential pathophysiologic mechanisms of NASH-induced kidney injury, and established a valuable model to study the pathogenesis of NASH-associated CKD. This is an important feature of fatty liver disease that has been largely overlooked but has clinical and prognostic importance.

Falsely Elevated Tacrolimus (FK506) Trough Levels in a Liver Transplant Recipient

Antibody-conjugated magnetic immunoassay (ACMIA) for tacrolimus (FK506) may detect falsely elevated tacrolimus trough levels, a commonly underreported event. We report a case of falsely elevated whole-blood tacrolimus levels in a patient post-orthotopic liver transplantation. A 71-year-old male patient underwent liver transplantation in 2012. Post-transplantation, the patient was immediately started on tacrolimus for maintenance immunosuppression. His most recent dose was 0.5 mg four times weekly. During monitoring, trough levels were at 25.9 ng/mL using ACMIA. After this result, a decision was made to hold tacrolimus. After holding tacrolimus for seven days, detected trough levels were still continually greater than 20 ng/mL. Upon suspicion of falsely elevated results, liquid chromatography with mass spectroscopy (LC-MS) was used to check tacrolimus trough levels. Results showed normal trough levels of 7.6 ng/mL. Because of its narrow therapeutic window, tacrolimus levels need to be carefully monitored throughout treatment. When high tacrolimus levels are detected using ACMIA without a correlating clinical scenario, trough levels should be re-confirmed using LC-MS to prevent clinical decisions from being made based on falsely elevated results.

Predictive Value of Fatty Liver Index for Long-Term Cardiovascular Events in Patients Receiving Liver Transplantation: The COLT Study

BACKGROUND AND AIMS

Cardiovascular disease (CVD) is the leading cause of early mortality in orthotopic liver transplantation (OLT) patients. The fatty liver index (FLI) is strongly associated with carotid and coronary atherosclerosis, as well as cardiovascular mortality, surpassing traditional risk factors. Given the lack of data on FLI as a predictor of cardiovascular events in OLT recipients, we conducted a retrospective study to examine this topic.

METHODS AND RESULTS

We performed a multicenter retrospective analysis of adult OLT recipients who had regular follow-up visits every three to six months (or more frequently if necessary) from January 1995 to December 2020. The minimum follow-up period was two years post-intervention. Anamnestic, clinical, anthropometric and laboratory data were collected, and FLI was calculated for all patients.

CLINICAL TRIAL

gov registration ID NCT05895669. A total of 110 eligible patients (median age 57 years [IQR: 50-62], 72.7% male) were followed for a median duration of 92.3 months (IQR: 45.7-172.4) post-liver transplantation. During this period, 16 patients (14.5%) experienced at least one adverse cardiovascular event (including fatal and non-fatal myocardial infarction and stroke). Receiver Operating Characteristic (ROC) analysis identified a cut-off value of 66.0725 for predicting cardiovascular events after OLT, with 86.7% sensitivity and 63.7% specificity (68% vs. 31%; p = 0.001). Kaplan-Meier analysis showed that patients with FLI > 66 had significantly reduced cardiovascular event-free survival than those with FLI ≤ 66 (log-rank: 0.0008). Furthermore, multivariable Cox regression analysis demonstrated that FLI > 66 and pre-OLT smoking were independently associated with increased cardiovascular risk.

CONCLUSIONS

Our findings suggest that FLI > 66 and pre-OLT smoking predict cardiovascular risk in adult OLT recipients.

Elevated Liver Fibrosis Progression in Isolated PSC Patients and Increased Malignancy Risk in a PSC-IBD Cohort: A Retrospective Study

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease often associated with inflammatory bowel disease (IBD), particularly ulcerative colitis (CU), and rarely with Crohn's disease (CD). Various long-term analyses show different rates of cancer and the need for orthotopic liver transplantation (OLT) in patients with isolated PSC and with concomitant IBD, respectively. However, data on the detailed course of PSC with or without IBD are limited. We aimed to analyze the clinical disease course of PSC patients without IBD compared to PSC patients with UC and CD, respectively. A retrospective data analysis of patients with isolated PSC (n = 41) and of patients with concomitant IBD (n = 115) was performed. In detail, PSC disease characteristics including occurrence of dominant stenoses, liver cirrhosis, OLT and malignancy, as well as the temporal course of PSC activity and disease progression, were analyzed. A multivariable Cox regression model and a Fine-Gray competing risk model were further used for the independent risk factor analysis of cirrhosis development and OLT. Patients with isolated PSC were significantly older at first diagnosis than patients with PSC-IBD (39 vs. 28 years, p = 0.02). A detailed analysis of the course of PSC revealed a faster PSC progression after initial diagnosis in isolated PSC patients compared to PSC-IBD including significantly earlier diagnosis of dominant stenoses (29 vs. 74 months, p = 0.021) and faster progression to liver cirrhosis (38 vs. 103 months, p = 0.027). Patients with isolated PSC have a higher risk of developing cirrhosis than patients with PSC-IBD (Gray's test p = 0.03). OLT was more frequently performed in male patients with isolated PSC compared to males with coincident IBD (48% (n = 13) vs. 33% (n = 25), p = 0.003). Colorectal carcinoma was significantly more often diagnosed in patients with PSC-IBD than in isolated PSC (8.7% vs. 0%, p = 0.042). Patients with isolated PSC seem to have a different clinical course of disease than PSC patients with concomitant IBD characterized by a more pro-fibrotic disease course with earlier onset of liver cirrhosis and dominant stenosis but with less malignancy. These data may be interpreted as either a more progressive disease course of isolated PSC or a later diagnosis of the disease at an advanced disease stage. The different clinical courses of PSC and the underlying mechanisms of the gut-liver axis need further attention.

Corrigendum: Application of cholecystic duct plasty in the prevention of biliary complications following orthotopic liver transplantation

[This corrects the article DOI: 10.3389/fsurg.2023.1087327.].

Perioperative Myocardial Infarction Following Dabigatran Reversal With Idarucizumab in a Patient Undergoing Orthotopic Liver Transplantation

Insufficient information is available regarding the administration of anticoagulants, specifically direct oral anticoagulants, in individuals with cirrhosis awaiting liver transplantation. In this report, we present a case of a 66-year-old male with atrial fibrillation treated with dabigatran who received idarucizumab prior to orthotopic liver transplantation. Hemostatic status was monitored throughout the procedure with both conventional hemostatic tests and point-of-care viscoelastic hemostatic assays. The patient suffered an intraoperative myocardial infarction, which could be related to the use of idarucizumab.

Differences in the Time Course of Recovery from Brain and Liver Dysfunction in Conventional Long-Term Treatment of Wilson Disease

BACKGROUND

The aim of this study was to demonstrate that both neurological and hepatic symptoms respond to copper chelation therapy in Wilson disease (WD). However, the time course of their recovery is different.

METHODS

Eighteen patients with neurological WD from a single specialized center who had been listed for liver transplantation during the last ten years and two newly diagnosed homozygous twins were recruited for this retrospective study. The mean duration of conventional treatment was 7.3 years (range: 0.25 to 36.2 years). A custom Wilson disease score with seven motor items, three non-motor items, and 33 biochemical parameters of the blood and urine, as well as the MELD score, was determined at various checkup visits during treatment. These data were extracted from the charts of the patients.

RESULTS

Treatment was initiated with severity-dependent doses (≥900 mg) of D-penicillamine (DPA) or triethylene-tetramin-dihydrochloride (TRIEN). The motor score improved in 10 and remained constant in 8 patients. Worsening of neurological symptoms was observed only in two patients who developed comorbidities (myasthenia gravis or hemispheric stroke). The neurological symptoms continuously improved over the years until the majority of patients became only mildly affected. In contrast to this slow recovery of the neurological symptoms, the MELD score and liver enzymes had already started to improve after 1 month and rapidly improved over the next 6 months in 19 patients. The cholinesterase levels continued to increase significantly (p < 0.0074) even further. One patient whose MELD score indicated further progression of liver disease received an orthotopic liver transplantation 3 months after the diagnosis of WD and the onset of DPA treatment.

CONCLUSIONS

Neurological and hepatic symptoms both respond to copper chelation therapy. For patients with acute liver failure, the first 4 months are critical. This is the time span in which patients have to wait either for a donor organ or until significant improvement has occurred under conventional therapy. For patients with severe neurological symptoms, it is important that they are treated with fairly high doses over several years.

First Successful Liver-Alone Transplantation for TERT (Telomerase Reverse Transcriptase)-Telomeropathy-Related Hepatoportal Sclerosis Cirrhosis

Hepatoportal sclerosis is a rare but well-described condition leading to end-stage liver disease. Telomeropathy is a rare genetic disorder which manifests as premature senescence of cells leading to multisystem disease involving bone marrow, lungs and skin. To the best of our knowledge, there is no report of telomeropathy precipitating end-stage liver disease. Our case presented hepatopulmonary syndrome. Herein, we report a successful liver transplantation in a patient who suffered hepatoportal cirrhosis from telomerase reverse transcriptase (TERT)-telomeropathy.

Case report: Immediate revascularization for symptomatic hepatic artery pseudoaneurysm after orthotopic liver transplantation? A case series and literature review

Introduction

Hepatic artery pseudoaneurysm (HAPA), a rare vascular complication that can develop after liver transplantation, is associated with a high mortality rate and graft loss. To salvage the liver graft, immediate revascularization, either through surgical or endovascular intervention, is required. However, currently there is no consensus on the optimal strategy. Here, we report three cases of liver transplant recipients diagnosed with HAPA and treated with immediate revascularization. In addition, we present an overview of HAPA cases described in the literature and make recommendations on how to treat this rare complication.

Methods

All adults transplanted in our center between 2005 and 2021 were retrospectively reviewed. Literature search was done in PubMed for original studies between 1980 and 2021 reporting early hepatic artery (pseudo) aneurysm after liver transplantation requiring either surgical or endovascular intervention.

Results

From a total of 1,172, 3 liver transplant patients were identified with a symptomatic HAPA and treated with immediate revascularization. HAPA occurred 73, 27, and 8 days after liver transplantation and was treated with immediate revascularization (two surgical and one endovascular intervention). Literature review identified 127 cases of HAPA. HAPA was managed with endovascular therapy in 20 cases and by surgical intervention in 89 cases. Overall reported mortality rate was 39.6%, whereas overall graft survival was 45.2%.

Conclusion

Immediate surgical or radiological interventional excision and prompt revascularization to salvage liver grafts is feasible but still associated with a high mortality.

Quality of Life Outcomes for Patients Who Underwent Conventional Resection and Liver Transplantation for Locally Advanced Hepatoblastoma

Hepatoblastoma is the most common malignant liver tumor of childhood, with liver transplant and extended resection used as surgical treatments for locally advanced tumors. Although each approach has well-described post-operative complications, quality-of-life outcomes have not been described following the two interventions. Long-term pediatric survivors of hepatoblastoma who underwent conventional liver resection or liver transplantation at a single institution from January 2000-December 2013 were recruited to complete quality-of-life surveys. Survey responses for the Pediatric Quality of Life Generic Core 4.0 (PedsQL, n = 30 patient and n = 31 parent surveys) and Pediatric Quality of Life Cancer Module 3.0 (PedsQL-Cancer, n = 29 patient and n = 31 parent surveys) were collected from patients and parents. The mean total patient-reported PedsQL score was 73.7, and the parent-reported score was 73.9. There were no significant differences in scores on the PedsQL between patients who underwent resection compared to those who underwent transplantation (p > 0.05 for all comparisons). On the PedsQL-Cancer module, procedural anxiety scores were significantly lower for patients who underwent resection as compared to transplant (M = 33.47 points less, CI [-60.41, -6.53], p-value 0.017). This cross-sectional study demonstrates that quality of life outcomes are overall similar among patients receiving transplants and resections. Patients who received a resection reported worse procedural anxiety.

The Current Role and Future Applications of Machine Perfusion in Liver Transplantation

The relative paucity of donor livers suitable for transplantation has sparked innovations to preserve and recondition organs to expand the pool of transplantable organs. Currently, machine perfusion techniques have led to the improvement of the quality of marginal livers and to prolonged cold ischemia time and have allowed for the prediction of graft function through the analysis of the organ during perfusion, improving the rate of organ use. In the future, the implementation of organ modulation might expand the scope of machine perfusion beyond its current usage. The aim of this review was to provide an overview of the current clinical use of machine perfusion devices in liver transplantation and to provide a perspective for future clinical use, including therapeutic interventions in perfused donor liver grafts.

Application of cholecystic duct plasty in the prevention of biliary complications following orthotopic liver transplantation

Background

The purpose was aimed to evaluate the safety and effectiveness of cholecystic duct plasty (CDP) and biliary reconstruction techniques preventing biliary complications following orthotopic liver transplantation (OLT) first proposed by our center.

Methods

127 enrolled patients who underwent LT in our center from January 2015 to December 2019 were analyzed retrospectively. According to the mode of biliary tract reconstruction, patients were divided into CDP group (Group 1, n = 53) and control group (Group 2, n = 74). The differences of perioperative general data, biliary complications and long-term prognosis between two groups were compared and analyzed.

Results

All patients completed the operation successfully, the incidence of perioperative complications was 22.8%. There was no significant difference in perioperative general data and complications between the two groups. Follow-up ended in June 2020, with a median follow-up period of 31 months. During the follow-up period, biliary complications occurred in 26 patients, with an overall incidence of 20.5%. The overall incidence of biliary complications and anastomotic stenosis in Group 1 was lower than that in Group 2 (P < 0.05). There was no significant difference in overall prognosis between the two groups (P = 0.274), however, the cumulative incidence of biliary complications in Group 1 was lower than that in Group 2 (P = 0.035).

Conclusion

Reconstruction of common bile duct by CDP represents considerable safety and practicability, particularly for patients with small diameter of common bile duct or wide discrepancy of bile duct size between donor and recipient.

Fibrosing Cholestatic Hepatitis Masquerading Acute Rejection in Hepatitis C Virus-Positive Donor Liver Graft

Fibrosing cholestatic hepatitis is a rare complication that manifests in patients receiving organ transplantation from seropositive (hepatitis C virus or hepatitis B virus) donors. We report a rare case of such a phenomenon in the immediate post-transplant period.

Implications of Pleural Fluid Composition in Persistent Pleural Effusion following Orthotopic Liver Transplant

Persistent pleural effusions (PPEf) represent a known complication of orthotopic liver transplant (OLT). However, their clinical relevance is not well described. We evaluated the clinical, biochemical, and cellular characteristics of post-OLT PPEf and assessed their relationship with longitudinal outcomes. We performed a retrospective cohort study of OLT recipients between 2006 and 2015. Included patients had post-OLT PPEf, defined by effusion persisting >30 days after OLT and available pleural fluid analysis. PPEf were classified as transudates or exudates (Exud^Light) by Light's criteria. Exudates were subclassified as those with elevated lactate dehydrogenase (Exud^LDH) or elevated protein (Exud^Prot). Cellular composition was classified as neutrophil- or lymphocyte-predominant. Of 1602 OLT patients, 124 (7.7%) had PPEf, of which 90.2% were Exud^Light. Compared to all OLT recipients, PPEf patients had lower two-year survival (HR 1.63; p = 0.002). Among PPEf patients, one-year mortality was associated with pleural fluid RBC count (p = 0.03). While Exud^Light and Exud^Prot showed no association with outcomes, Exud^LDH were associated with increased ventilator dependence (p = 0.03) and postoperative length of stay (p = 0.03). Neutrophil-predominant effusions were associated with increased postoperative ventilator dependence (p = 0.03), vasopressor dependence (p = 0.02), and surgical pleural intervention (p = 0.02). In summary, post-OLT PPEf were associated with increased mortality. Ninety percent of these effusions were exudates by Light's criteria. Defining exudates using LDH only and incorporating cellular analysis, including neutrophils and RBCs, was useful in predicting morbidity.

Orthotopic Transplantation of Functional Bioengineered Livers in Rats

Functional bioengineered livers (FBLs) are promising alternatives to orthotopic liver transplantation. However, orthotopic transplantation of FBLs has not yet been reported. This study aimed to perform the orthotopic transplantation of FBLs in rats subjected to complete hepatectomy. FBLs were developed using rat whole decellularized liver scaffolds (DLSs) with human umbilical vein endothelial cells implanted via the portal vein, and human bone marrow mesenchymal stem cells (hBMSCs) and mouse hepatocyte cell line implanted via the bile duct. FBLs were evaluated in terms of endothelial barrier function, biosynthesis, and metabolism and orthotopically transplanted into rats to determine the survival benefit. The FBLs with well-organized vascular structures exhibited endothelial barrier function, with reduced blood cell leakage. The implanted hBMSCs and hepatocyte cell line were well aligned in the parenchyma of the FBLs. The high levels of urea, albumin, and glycogen in the FBLs indicated biosynthesis and metabolism. Orthotopic transplantation of FBLs achieved a survival time of 81.38 ± 4.263 min in rats (n = 8) subjected to complete hepatectomy, whereas control animals (n = 4) died within 30 min (p < 0.001). After transplantation, CD90-positive hBMSCs and the albumin-positive hepatocyte cell line were scattered throughout the parenchyma, and blood cells were limited within the vascular lumen of the FBLs. In contrast, the parenchyma and vessels were filled with blood cells in the control grafts. Thus, orthotopic transplantation of whole DLS-based FBLs can effectively prolong the survival of rats subjected to complete hepatectomy. In summary, this work was the first to perform the orthotopic transplantation of FBLs, with limited survival benefits, which still has important value for the advancement of bioengineered livers.

Construction and validation of a pulmonary complication score for patients after liver transplantation

PURPOSE

Identification of preoperative risk factors associated with pulmonary complications may benefit high-risk patients from more intense surveillance and earlier interventions in liver transplantation (LT). Our study aimed to identify risk factors for predicting pulmonary complications in LT patients.

MATERIALS AND METHODS

The discovery data set enrolled 208 patients who underwent orthotopic LT while the validation data set included 117 patients. Clinical data were collected from medical history retrospectively and risk factors were determined by logistic regression analyses. The pulmonary complication score (PCS-LT) was established and validated for predicting pulmonary complications after LT.

RESULTS

In the discovery data set, 47 (22.6%) participants experienced pulmonary complications following LT. Four independent risk factors for pulmonary complications were identified by multivariate logistic regression analysis, including preoperative abnormal pulmonary function (OR = 4.743, p < .001), elevated lymphocyte count (OR = 2.336, p = .027), hypoproteinemia (OR = 2.635, p = .030), and hypokalemia (OR = 5.257, p = .003), and PCS-LT based on these factors was established. ROC analyses showed PCS-LT could predict PC in both the discovery data set (area under curve [AUC] .752, 95% confidence interval [CI] .687-.809) and the validation data set (AUC .754, 95% CI, .666-.829). The PCS-LT demonstrated superior predictive value (AUC .735, 95% CI, .703-.799) to APACHE II score (AUC .653, 95% CI, .599-.705) in the combined data set (p = .032). Meanwhile, PCS-LT > 1 was used as the cut-off value and has prognostic significance in LT patients.

CONCLUSIONS

The PCS-LT score, consisting of abnormal pulmonary function, elevated lymphocyte count, hypoproteinemia, and hypokalemia, could predict pulmonary complications after LT.

High plasma levels of betaine, a trimethylamine N-Oxide-related metabolite, are associated with the severity of cirrhosis

BACKGROUND AND AIMS

The gut microbiome-related metabolites betaine and trimethylamine N-oxide (TMAO) affect major health issues. In cirrhosis, betaine metabolism may be diminished because of impaired hepatic betaine homocysteine methyltransferase activity, whereas TMAO generation from trimethylamine may be altered because of impaired hepatic flavin monooxygenase expression. Here, we determined plasma betaine and TMAO levels in patients with end-stage liver disease and assessed their relationships with liver disease severity.

METHODS

Plasma betaine and TMAO concentrations were measured by nuclear magnetic resonance spectroscopy in 129 cirrhotic patients (TransplantLines cohort study; NCT03272841) and compared with levels from 4837 participants of the PREVEND cohort study. Disease severity was assessed by Child-Pugh-Turcotte (CPT) classification and Model for End-stage Liver Disease (MELD) score.

RESULTS

Plasma betaine was on average 60% higher (p < .001), whereas TMAO was not significantly lower in cirrhotic patients vs. PREVEND population (p = .44). After liver transplantation (n = 13), betaine decreased (p = .017; p = .36 vs. PREVEND population), whereas TMAO levels tended to increase (p = .085) to higher levels than in the PREVEND population (p = .003). Betaine levels were positively associated with the CPT stage and MELD score (both p < .001). The association with the MELD score remained in the fully adjusted analysis (p < .001). The association of TMAO with the MELD score did not reach significance (p = .11). Neither betaine nor TMAO levels were associated with mortality on the waiting list for liver transplantation (adjusted p = .78 and p = .44, respectively).

CONCLUSION

Plasma betaine levels are elevated in cirrhotic patients in parallel with disease severity and decrease after liver transplantation.

[Endoscopic intraluminal treatment of early biliary complications after orthotopic liver transplantation]

OBJECTIVE

To improve the outcomes after orthotopic liver transplantation (OLT) followed by early biliary complications via endoscopic bilioduodenal stenting.

MATERIAL AND METHODS

The study enrolled 41 patients with early biliary complications within 90 days after OLT. All patients underwent endoscopic treatment between 2001 and 2021. There were 34 (82.9%) men and 7 (17.1%) women aged 48.5±12.5 years. Strictures and failure of biliary anastomosis occurred in 33 (80.5%) and 8 (19.5%) patients, respectively.

RESULTS

After endoscopic treatment, serum bilirubin normalized in 3.3±0.86 days in patients with strictures (23.7 (16.4; 34.5) mmol/l, p<0.001). Diameter of lobar ducts as a criterion of biliary hypertension was normalized after 4 (2.5; 5.5) days (p<0.001). Bile leakage after stenting with a covered self-expanding stent regressed in all 7 patients after 3 (2; 5) days. In 1 patient, bile output through the drainage stopped in 8 days after bilioduodenal stenting with a plastic stent.

CONCLUSION

Endoscopic bilioduodenal stenting is always effective and minimally invasive treatment after liver transplantation followed by early biliary complications (failure or stricture of anastomosis). This approach minimizes postoperative complications (9.8%) that do not require surgical intervention (Clavien-Dindo grade I).

Intracerebral opportunistic infections caused by immunosuppressants after orthotopic liver transplantation: Report of two cases and literature review

Central nervous system (CNS) infections in adults are rare because of normal immunity and the existence of the blood brain barrier, which prevents the invasion of pathogenic microorganisms. Liver transplant recipients are at an increased risk of opportunistic infections (OI) due to immunosuppressive therapy compared to those with normal immunity. Early diagnosis and timely implementation of treatment are critical for the successful treatment of these infections. We present two cases of intracerebral OI after orthotopic liver transplantation (OLT), with different clinical presentations. Patient 1 presented with epileptic seizures, mainly manifested as unresponsiveness, unconsciousness, and coma complicated with involuntary limb twitching. Patient 2 presented with a consciousness disorder, mainly manifested as unclear consciousness content, poor orientation, calculation power, and logical ability. Next-generation sequencing (NGS) examination of the cerebrospinal fluid confirmed human herpesvirus 6 B (HHV-6B) infection in patient 1 and intracranial Aspergillus infection in patient 2. Intracranial OI has insidious onset and atypical clinical manifestations. NGS can allow for the proper diagnosis and monitoring of the effects of treatment.

IL-18BP Improves Early Graft Function and Survival in Lewis-Brown Norway Rat Orthotopic Liver Transplantation Model

Interleukin-18 (IL-18) can effectively activate natural killer (NK) cells and induce large concentrations of interferon-γ (IFN-γ). In healthy humans, IL-18 binding protein (IL-18BP) can inhibit the binding of IL-18 to IL-18R and counteract the biological action of IL-18 due to its high concentration and high affinity, thus preventing the production of IFN-γ and inhibiting NK-cell activation. Through previous studies and the phenomena observed by our group in pig-non-human primates (NHPs) liver transplantation experiments, we proposed that the imbalance in IL-18/IL-18BP expression upon transplantation encourages the activation, proliferation, and cytotoxic effects of NK cells, ultimately causing acute vascular rejection of the graft. In this research, we used Lewis-Brown Norway rat orthotopic liver transplantation (OLTx) as a model of acute vascular rejection. AAV8-Il18bp viral vectors as gene delivery vehicles were constructed for gene therapy to overexpress IL-18BP and alleviate NK-cell rejection of the graft after transplantation. The results showed that livers overexpressing IL-18BP had reduced damage and could function longer after transplantation, effectively improving the survival time of the recipients.

Cryoablation for Renal Cell Carcinoma Prior to Liver Transplantation: A Case Report

Extrahepatic malignancies are a relatively rare incidental finding during liver transplant work-up that provides a significant barrier to continued transplant evaluation and requires treatment to limit the risk of recurrence. There have only been 11 previously reported cases of pre-liver transplant renal cell carcinoma (RCC), of which all underwent partial or radical nephrectomy. Percutaneous cryoablation therapy has been gaining acceptance as a curative treatment alternative for RCC and is a new therapeutic standard for patients who are poor candidates for surgical resection. Recent studies have demonstrated the safety and efficacy of cryoablation for RCC in native kidneys and in solid masses in kidney allografts, but there is no data on the efficacy or recurrence of RCC when cryoablation is used for the treatment of RCC in a native kidney prior to solid organ transplantation. The patient underwent percutaneous cryoablation therapy of a T1a RCC of the native kidney 10 months prior to orthotopic liver transplant (OLT) without subsequent partial or radical nephrectomy. At seven years post-ablation therapy, the patient has no evidence of tumor recurrence despite immunosuppressive therapy post-transplantation. Cryoablation is potentially a safe and highly effective means of treating RCC in patients who are not candidates for nephrectomy secondary to complications associated with end-stage liver disease. In our case, the patient was treated with cryoablation and received standard post-transplant immunosuppression without recurrence of RCC at seven years. More studies are needed to determine inclusion and exclusion criteria for cryoablation and to confirm long-term efficacy as well as a strategy for duration and frequency of surveillance in these patients.

New onset atrial fibrillation during orthotopic liver transplantation induced by iced saline injection for transpulmonary thermodilution: a case report

Transpulmonary thermodilution is often used to measure extravascular lung water during liver transplantation. Here, the case of new onset atrial fibrillation during orthotopic liver transplantation, which may have been induced by iced saline injection for transpulmonary thermodilution measurement, is described. A 52-year-old male patient underwent orthotopic liver transplantation due to alcoholic cirrhosis combined with portal hypertension. During dissection of the recipient liver, transpulmonary thermodilution was performed. At 3 minutes following iced saline injected, atrial fibrillation occurred, the ventricular rate increased to more than 120 beats per min, and blood pressure dropped to 75/50 mmHg. Massive haemorrhage, inferior vena cava clamping, electrolyte disorder, acid-base balance disorder, and hypothermia were all ruled out, and iced saline injection was suspended. Hemodynamic stability was maintained with phenylephrine and lanatocide C (cedilanid), and chemical cardioversion was performed using amiodarone. During the reperfusion phase, transient hemodynamic instability was managed by norepinephrine. The neohepatic phase was uneventful. Atrial fibrillation lasted for 5 days and reversed to sinus rhythm automatically. The patient was hemodynamically stable during this period, and recovery was smooth with no thromboembolic events. In conclusion, atrial fibrillation may be induced by iced saline injection for transpulmonary thermodilution measurement during orthotopic liver transplantation.

The Benefits of Fibrinolysis Combined with Venous Systemic Oxygen Persufflation (VSOP) in a Rat Model of Donation after Circulatory Death and Orthotopic Liver Transplantation

Organ shortage has led to the increasing utilization of livers retrieved from donors after circulatory death (DCD). These pre-damaged organs are susceptible to further warm ischemia and exhibit minimal tolerance for cold storage. The aim was thus to examine the effects of fibrinolysis combined with Venous Systemic Oxygen Persufflation (VSOP) on the preservation of DCD livers in vivo. Livers of male Lewis rats were explanted after 45 min of warm ischemia, cold-stored for 18 h, and transplanted into a recipient animal. Livers were left untreated or underwent either VSOP or fibrinolysis via Streptokinase (SK) or received combined SK and VSOP. Combined treatment exhibited improved microvascular flow at 168 h (p = 0.0009) and elevated microperfusion velocity at 24 h post-transplantation (p = 0.0007). Combination treatment demonstrated increased portal venous flow (PVF) at 3 and 24 h post-transplantation (p = 0.0004, p < 0.0001), although SK and VSOP analogously achieved increases at 24 h (p = 0.0036, p = 0.0051). Enzyme release was decreased for combination treatment (p = 0.0002, p = 0.0223) and lactate dehydrogenase (LDH) measurements were lower at 24 h post-transplantation (p = 0.0287). Further supporting findings have been obtained in terms of serum cytokine levels and in the alterations of endothelial injury markers. The combination treatment of SK + VSOP might provide improved organ integrity and viability and may therefore warrant further investigation as a potential therapeutic approach in the clinical setting of DCD.

Profoundly Disturbed Lipoproteins in Cirrhotic Patients: Role of Lipoprotein-Z, a Hepatotoxic LDL-like Lipoprotein

Detailed information regarding lipoprotein concentrations and subfractions in cirrhotic patients before and after orthotopic liver transplantation (OLT) is lacking. Lipoprotein-Z (LP-Z) is a recently characterised abnormal, hepatotoxic free cholesterol-rich low-density lipoprotein (LDL)-like lipoprotein. We determined the lipoprotein profiles, including LP-Z, in cirrhotic patients and OLT recipients and assessed the prognostic significance of LP-Z on the OLT waiting list. We performed analyses in cirrhotic transplant candidates and non-cirrhotic OLT recipients. A population-based cohort was used as reference. The setting was a University hospital. Lipoprotein particle concentrations and subfractions were measured by nuclear magnetic resonance spectroscopy. In the cirrhotic patients (N = 130), most measures of triglyceride-rich lipoproteins (TRL), LDL, and high-density lipoproteins (HDL) were much lower compared to the OLT recipients (N = 372) and controls (N = 6027) (p < 0.01). In the OLT recipients, many lipoprotein variables were modestly lower, but HDL-cholesterol, triglycerides, and TRL and HDL size were greater vs. the control population. LP-Z was measurable in 40 cirrhotic patients and 3 OLT recipients (30.8% vs. 0.8%, p < 0.001). The cirrhotic patients with measurable LP-Z levels had profoundly lower HDL-cholesterol and particle concentrations (p < 0.001), and worse Child Pugh Turcotte classifications and MELD scores. The presence of LP-Z (adjusted for age, sex, and MELD score) predicted worse survival in cirrhotic patients (HR per 1 LnSD increment: 1.11, 95%CI 1.03−1.19, p = 0.003). In conclusion, cirrhotic patients have considerably lower plasma concentrations of all major lipoprotein classes with changes in lipoprotein subfraction distribution. After OLT, these lipoprotein abnormalities are in part reversed. LP-Z is associated with cirrhosis. Its presence may translate in disturbed HDL metabolism and worse survival.

Migration of fully covered self-expandable metallic stents used to treat anastomotic strictures after orthotopic liver transplantation: A single-center, retrospective analysis

Insertion of a fully covered self-expandable metallic stent (FCEM) through endoscopic retrograde cholangiopancreatography is an effective solution for biliary anastomotic stricture following orthotopic liver transplantation (OLT). However, FCEM migration continues to plague patients. This study aimed to evaluate the FCEM migration rate in our center, and to investigate the factors increasing the migration risk for FCEM.The study enrolled 43 post-OLT patients with confirmed duct-to-duct AS. The effects of age, gender, albumin, alanine aminotransferase, aspartate aminotransferase (AST), γ-glutamyl transpeptidase, alkaline phosphatase, total bilirubin, direct bilirubin, ABO (blood group system consists of four antigens) incompatibility, stricture length, FCEM brand, FCEM length, donor liver and recipient bile duct diameters, size mismatches between the donor and recipient bile ducts >2 mm, diabetes and/or hypertension status, endoscopic sphincterotomy status, the use of plastic stents or nasobiliary drainage prior to FCEM implantation, duration from OLT to FCEM placement, and OLT etiology on FCEM migration were retrospectively analyzed.The FCEM migration rate was 48.8% (21/43) at 6 months. The serum AST level was significantly higher in the migration group than that in the nonmigration group (52.48 vs 29.50 U/L, P < .05). A lower serum AST level was associated with a decreased risk of FCEM migration in post-OLT patients with duct-to-duct anastomotic stricture (hazard ratio = 0.968, 95% confidence interval: 0.940-0.996, P = .028).In this single-center, retrospective cohort study, we showed that an elevated serum AST level was a potential risk factor for FCEM migration.

Prediction of Graft Survival Post-liver Transplantation by L-GrAFT Risk Score Model, EASE Score, MEAF Scoring, and EAD

Background: Early allograft dysfunction (EAD) is correlated with poor patient or graft survival in liver transplantation. However, the power of distinct definitions of EAD in prediction of graft survival is unclear. Methods: This retrospective, single-center study reviewed data of 677 recipients undergoing orthotopic liver transplant between July 2015 and June 2020. The following EAD definitions were compared: liver graft assessment following transplantation (L-GrAFT) risk score model, early allograft failure simplified estimation score (EASE), model for early allograft function (MEAF) scoring, and Olthoff criteria. Risk factors for L-GrAFT₇ high risk group were evaluated with univariate and multivariable logistic regression analysis. Results: L-GrAFT₇ had a satisfied C-statistic of 0.87 in predicting a 3-month graft survival which significantly outperformed MEAF (C-statistic = 0.78, P = 0.01) and EAD (C-statistic = 0.75, P < 0.001), respectively. L-GrAFT₁₀, EASE was similar to L-GrAFT₇, and they had no statistical significance in predicting survival. Laboratory model for end-stage liver disease score and cold ischemia time are risk factors of L-GrAFT₇ high-risk group. Conclusion: L-GrAFT₇ risk score is capable for better predicting the 3-month graft survival than the MEAF and EAD in a Chinese cohort, which might standardize assessment of early graft function and serve as a surrogate endpoint in clinical trial.

Cardiovascular Evaluation of Liver Transplant Patients by Using Coronary Calcium Scoring in ECG-Synchronized Computed Tomographic Scans

Background: The goal of cardiac evaluation of patients awaiting orthotopic liver transplantation (OLT) is to identify the patients at risk for cardiovascular events (CVEs) in the peri- and postoperative periods by opportunistic evaluation of coronary artery calcium (CAC) in non-gated abdominal computed tomographs (CT). Methods: We hypothesized that in patients with OLT, a combination of Lee’s revised cardiac index (RCRI) and CAC scoring would improve diagnostic accuracy and prognostic impact compared to non-invasive cardiac testing. Therefore, we retrospectively evaluated 169 patients and compared prediction of CVEs by both methods. Results: Standard workup identified 22 patients with a high risk for CVEs during the transplant period, leading to coronary interventions. Eighteen patients had a CVE after transplant and a CAC score > 0. The combination of CAC and RCRI ≥ 2 had better negative (NPV) and positive predictive values (PPV) for CVEs (NPV 95.7%, PPV 81.6%) than standard non-invasive stress tests (NPV 92.0%, PPV 54.5%). Conclusion: The cutoff value of CAC > 0 by non-gated CTs combined with RCRI ≥ 2 is highly sensitive for identifying patients at risk for CVEs in the OLT population.

The Success of a Simulation-Based Transesophageal Echocardiography Course for Liver Transplant Anesthesiologists

INTRODUCTION

Transesophageal echocardiography (TEE) is increasingly used for intraoperative management during orthotopic liver transplantation. Proficient TEE use requires skill and knowledge to accurately assess the hemodynamic status and guide clinical management. Currently there are no TEE educational tracks specifically focused on perioperative liver transplant management and barriers to obtaining basic certification exist.

METHODS

A 4-hour simulation-based learning (SBL) course was provided to improve liver transplant anesthesiologist TEE knowledge and skill. Learners received training and education using a TEE simulator in small groups focusing on basic image acquisition, relevant anatomy, hemodynamic calculations, and pathology germane to the liver transplant period. Knowledge assessment and survey responses were assessed at the beginning and completion of the course. Learners completed TEE examinations with simulated pathology during high-fidelity simulations following the course.

RESULTS

Seventeen anesthesiologists completed the course. The median baseline knowledge assessment score was 55.0% (37-70). The median postcourse knowledge assessment score improved to 95.0% (94-100) (P < .001). All anesthesiologists were able to identify TEE pathology during high-fidelity simulation. Survey responses yielded significant median score improvement in all areas assessed using a 5-point Likert scale.

CONCLUSIONS

A small group, simulation TEE course delivered over 4 hours can increase knowledge and skill in TEE use for liver transplant anesthesiologists.

Transfusion requirements and alloimmunization to red blood cell antigens in orthotopic liver transplantation

BACKGROUND AND OBJECTIVES

Orthotopic liver transplantation (OLT) has been associated with high blood transfusion requirements. We evaluated the transfusion needs and frequency of alloimmunization to RBC antigens among OLT recipients pre- and post-transplantation.

MATERIALS AND METHODS

We reviewed the medical records of patients who underwent a first OLT between January 2007 and June 2017. Transfusions given only during the perioperative period, defined by 1 week before OLT until 2 weeks following OLT, were included in this study. Records were reviewed in June 2019 for updated antibody testing results.

RESULTS

A total of 970 patients underwent OLT during the study period. The median age of patients was 57 years; 608(62.7%) were male. During the perioperative period, transfused patients received an average of 10.7 (±10.7) RBC units, 15.6 (±16.2) thawed plasma units and 4.1 (±4.3) platelet units. At the time of OLT, a total of 101 clinically significant RBC alloantibodies were documented in 58(5.98%) patients. Fifty-three of these antibodies were directed against Rh blood group antigens. Twenty-two (37.9%) patients had more than one alloantibody. Patients with alloimmunization before OLT (N = 58) received perioperatively comparable number of RBCs to non-alloimmunized patients (10.5 ± 10.6 vs. 9.6 ± 10.7; p = 0.52). There was no significant difference in perioperative or intraoperative RBC transfusion between patients with one alloantibody and those with multiple alloantibodies. Only 16 patients (16/737; 2.17%) developed new alloantibodies at a median of 61 days after OLT. The overall alloimmunization rate was 9.8% (72/737), and female patients were more likely to be alloimmunized.

CONCLUSION

Blood transfusion requirements in OLT remain high. However, the rate of RBC alloimmunization was not higher than the general patient population.

Surgical Treatment for Intrahepatic, Peri-Hilar, and Distal Cholangiocarcinoma: 20-Single Institutional Year Experience

BACKGROUND

Surgical resection is the curative treatment for all subtypes of cholangiocarcinoma (CCA), including intrahepatic, hilar/peri-hilar, and distal. This study evaluates patients with CCA who underwent surgery and determines factors that impact their survival.

METHODS

A retrospective cohort study was performed for patients who underwent surgical resection for CCA at our institution from 1995 to 2016. Demographics, operative variables between CCA tumors, and postoperative complications were analyzed. Predictors of overall and recurrence-free survival were determined via statistical analysis.

RESULTS

A total of 170 patients with a mean age of 61 years old underwent surgical resection of intrahepatic (n = 64, 37.6%), hilar/peri-hilar (n = 75, 44.1%), and distal (n = 31, 18.2%) CCA. Operations performed included liver resections (n = 83, 48.8%), liver transplants (n = 56, 32.9%), and pancreaticoduodenectomies (n = 31, 18.2%). The overall survival rate at 1, 5, and 10 years was 81.1%, 32.4%, and 17.2%, respectively. Low pathological stage and negative resection margins were associated with lower recurrence and higher survival rates. Tumor location and the type of operation performed were not predictive of recurrence or OS in this cohort.

DISCUSSION

This study shows that definitive surgical resection with negative margins can result in long-term survival even at 10 years. Small tumor size and low pathological stage are predictive of higher survival rates post-surgery, emphasizing the importance of early diagnosis and appropriate surgical treatment in achieving positive outcomes.

Trends in indications and outcomes of liver transplantation in Canada: A multicenter retrospective study

The liver transplantation (LT) landscape is continuously evolving. We sought to evaluate trends in indications for LT in Canada and the impact of primary liver disease on post-LT outcomes using a national transplant registry. Adult patients who underwent a primary LT between 2000 and 2018 were retrospectively identified in the Canadian Organ Replacement Registry. Outcomes included post-LT patient and graft survival. A total of 5,722 LTs were identified. The number of LT per year increased from 251 in 2000 to 349 in 2018. The proportion of patients transplanted for HCV decreased from 31.5% in 2000 to 3.4% in 2018. In contrast, the percentage of transplants for HCC increased from 2.3% in 2000 to 32.4% in 2018, and those performed for NASH increased from 0.4% in 2005 to 12.6% in 2018. Year of transplant (per 1 year) was protective for both patient (HR:0.96,95%CI:0.94-0.97; P < 0.001) and graft survival (HR:0.97, 95%CI: 0.96-0.99; P = 0.001). Post-LT outcomes have improved over time in this nationwide analysis spanning 18 years. Moreover, trends in the indications for LT have changed, with HCC becoming the leading etiology. The decrease in the proportion of HCV patients and increase in those with NASH has implications on the evolving management of LT patients.

Clinical value and limitations of the preoperative C-reactive-protein-to-albumin ratio in predicting post-operative morbidity and mortality after deceased-donor liver transplantation: a retrospective single-centre study

Liver transplantation is still associated with a high risk of severe complications and post-operative mortality. This study examines the predictive value of the preoperative C-reactive-protein-to-albumin ratio (CAR) regarding perioperative morbidity and mortality in deceased-donor liver transplantation (DDLT) recipients. In total, 390 DDLT recipients between 05/2010 and 03/2020 were eligible. Predictive abilities of CAR were examined through receiver operating characteristic curve (ROC) analyses. Groups were compared using parametric and non-parametric tests as appropriate. Independent risk factors for morbidity and mortality were identified using uni- and multivariable logistic regression analyses. A good predictive ability for CAR was shown regarding perioperative morbidity (comprehensive complication index ≥75, Clavien-Dindo score ≥4a) and 12-month mortality, with an ideal cut-off of CAR = 26%. Patients with CAR>26% had significantly higher median CCI scores (60 vs. 43, P < 0.001), longer intensive care unit (ICU, 5 vs. 4 days, P < 0.001) and hospital (28 vs. 21 days, P < 0.001) stays and higher 12-month mortality rates (20% vs 6%, P < 0.001). Multivariable analyses identified CAR>26%, pre-OLT inpatient hospitalization (including ICU) and post-operative red blood cell transfusions as independent predictors of severe cumulative morbidity (CCI≥75). Preoperative CAR might be a reliable additional tool to predict perioperative morbidity and mortality in DDLT recipients.

Age-related changes in metabolites in young donor livers and old recipient sera after liver transplantation from young to old rats

Liver ageing not only damages liver function but also harms systemic metabolism. To better understand the mechanisms underlying liver ageing, we transplanted the livers of young rats to young and old rats and performed untargeted metabolomics to detect changes in the metabolites in the liver tissues and sera. A total of 153 metabolites in the livers and 83 metabolites in the sera were different between the old and young rats that did not undergo liver transplantation; among these metabolites, 7 different metabolites were observed in both the livers and sera. Five weeks after liver transplantation, the levels of 25 metabolites in the young donor livers were similar to those in the old rats, and this result probably occurred due to the effect of the whole‐body environment of the older recipients on the young livers. The 25 altered metabolites included organic acids and derivatives, lipids and lipid‐like molecules, etc. In the sera, the differences in 78 metabolites, which were significant between the young and old rats, were insignificant in the old recipient rats and made the metabolic profile of the old recipients more similar to that of the young recipients. Finally, combining the above metabolomic data with the transcriptomic data from the GEO, we found that the altered metabolites and genes in the liver were enriched in 9 metabolic pathways, including glycerophospholipid, arachidonic acid, histidine and linoleate. Thus, this study revealed important age‐related metabolites and potential pathways as well as the interaction between the liver and the whole‐body environment.

A prediction score model and survival analysis of acute kidney injury following orthotopic liver transplantation in adults

BACKGROUND

Acute kidney injury (AKI) is one of the postoperative complications following orthotopic liver transplantation (OLT), and is related to the high morbidity and mortality. Although there were numerous propensity factors for AKI, their cumulative influence remains unclear. Our aims were to develop a score model to predict postoperative AKI and to evaluate the impact of AKI on the recipients' long-term survival.

METHODS

We retrospectively analyzed 99 adult patients underwent OLT in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between October 2014 and July 2020. The patients were dichotomized into the non-AKI and the AKI groups according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria. We defined stage-1 AKI as mild AKI, stage-2 AKI and stage-3 AKI as severe AKI.

RESULTS

Overall, 29 (29.29%) patients developed AKI after OLT, of these, stage-1, stage-2, stage-3 account for 20.20% (20 of 99 patients), 2.02% (2 of 99 patients), 7.07% (7 of 99 patients), respectively; and 13.79% of postoperative AKI patients (4 of 29 patients) accepted renal replacement therapy (RRT). Operative time and MELD-Na score predicted the postoperative AKI, with odds ratio of 1.006, 1.061, respectively. The generated AKI prediction model is as follows: -5.594+0.007×operative time+0.060×MELD-Na. The area under the receiver operating characteristic curve (AUC) for the AKI prediction model was 0.762, and the sensitivity and specificity were 79.3%, 61.4%, respectively. There was no difference in long-term survival among the mild AKI group and the non-AKI group (P=0.751). However, the impact of severe AKI on long-term survival of patients was statistically significant when comparing the non-AKI group and the mild AKI group (P=0.001, P=0.011).

CONCLUSIONS

AKI occurs frequently in adult patients after OLT, and it poses a threat to patients' long-term survival. The severe AKI has negative impact on long-term survival, while the mild AKI has limited impact on long-term survival, compared with non-AKI group. The novel AKI prediction model has prognostic value in identifying patients at high risk for postoperative AKI.

The effects of cell surface CD47 downregulation on ischaemia-reperfusion injury during pig liver transplantation

This study aimed to investigate the effect of cell surface CD47 downregulation on ischaemia-reperfusion injury (IRI) during pig liver transplantation. Blood samples were collected from healthy miniature Bama pigs randomly and equally divided into CD47 antagonism (group A), without CD47 antagonism (group B) and a sham group (group C). Blood samples were collected from groups A and B at 0, 8 and 48 hours after establishment of the new liver through an indwelling tube in the right internal jugular vein. Blood samples were collected at the same time points after liver dissociation from group C. The expression of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) was detected by enzyme-linked immunosorbent assay (ELISA); CD47 expression was detected by Western blot; and liver function indices, including alanine aminotransferase (ALT) and aspartic transaminase (AST), were directly read by an automatic biochemical analyzer. The concentrations of both receptors in group A were significantly lower than groups B and C, at 8 and 48 hours after establishment of blood flow. At 8 and 48 hours in the new liver stage, the values of CD47 levels, ALT and AST in group A were significantly reduced compared to groups B and C (P < 0.05). The levels of CD47 in the three groups were consistent with the trends of the aforementioned observation indicators. The liver functions of the recipients were significantly improved by reducing the release of the inflammatory mediators. This study provides new ideas and intervention approaches for the treatment of IRI in liver transplantation.

Machine Learning Models to Predict Major Adverse Cardiovascular Events After Orthotopic Liver Transplantation: A Cohort Study

OBJECTIVE

To develop machine learning models that can predict post-transplantation major adverse cardiovascular events (MACE), all-cause mortality, and cardiovascular mortality in patients undergoing liver transplantation (LT).

DESIGN

Retrospective cohort study.

SETTING

High-volume tertiary care center.

PARTICIPANTS

The study comprised 1,459 consecutive patients undergoing LT between January 2008 and December 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

MACE, all-cause mortality, and cardiovascular mortality were modeled using logistic regression, least absolute shrinkage and selection surgery regression, random forests, support vector machine, and gradient-boosted modeling (GBM). All models were built by splitting data into training and testing cohorts, and performance was assessed using five-fold cross-validation based on the area under the receiver operating characteristic curve and Harrell's C statistic. A total of 1,459 patients were included in the final cohort; 1,425 (97.7%) underwent index transplantation, 963 (66.0%) were female, the median age at transplantation was 57 (11-70) years, and the median Model for End-Stage Liver Disease score was 20 (6-40). Across all outcomes, the GBM model XGBoost achieved the highest performance, with an area under the receiver operating curve of 0.71 (95% confidence interval [CI] 0.63-0.79) for MACE, a Harrell's C statistic of 0.64 (95% CI 0.57-0.73) for overall survival, and 0.72 (95% CI 0.59-0.85) for cardiovascular mortality over a mean follow-up of 4.4 years. Examination of Shapley values for the GBM model revealed that on the cohort-wide level, the top influential factors for postoperative MACE were age at transplantation, diabetes, serum creatinine, cirrhosis caused by nonalcoholic steatohepatitis, right ventricular systolic pressure, and left ventricular ejection fraction.

CONCLUSION

Machine learning models developed using data from a tertiary care transplantation center achieved good discriminant function in predicting post-LT MACE, all-cause mortality, and cardiovascular mortality. These models can support clinicians in recipient selection and help screen individuals who may be at elevated risk for post-transplantation MACE.

Stabilizing mast cells improves acute lung injury after orthotopic liver transplantation via promotion of apoptosis in polymorphonuclear neutrophils

Postoperative pulmonary complications including acute lung injury (ALI) and acute respiratory distress syndrome have contributed to mortality and morbidity of orthotopic liver transplantation (OLT) with unclear mechanisms. Mast cells (MCs) and polymorphonuclear neutrophils (PMNs) are the main inflammatory cells and participants in the process of ALI. The present study was designed to investigate the role of MCs and PMNs and their potential relation to ALI following OLT. Rat orthotopic autologous liver transplantation (OALT) model was designed to determine lung injury at different time points after liver reperfusion. We also evaluated the function of MCs and the effect of tumor necrosis factor-α (TNF-α) and tryptase on ALI and PMN apoptosis in rats subjected to OALT. Histological scores and inflammatory factor levels as well as PMN apoptosis were measured. Rats suffered from ALI after OALT, which was demonstrated by a collapse of the pulmonary architecture, pulmonary edema, and infiltration of inflammatory cells in alveolar and interstitial spaces, as well as increased levels of proinflammatory cytokines. ALI maximized at 8 h after OALT. However, PMN apoptosis lagged behind the pulmonary injury and maximized at 16 h after OALT, when the acute inflammation resolution initiated. MC stabilization, and tryptase and TNF-α inhibitors could significantly decrease the lung pathophysiologic scores accompanied by an increase in PMN apoptosis. ALI after OALT was associated with MC activation and PMN apoptosis. ALI progression might be affected by delayed PMN apoptosis, which was related to MC activation. Induction of PMN apoptosis might alleviate ALI after OALT.

COVID-19 in an international European liver transplant recipient cohort

OBJECTIVE

Knowledge on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in liver transplant recipients is lacking, particularly in terms of severity of the disease. The aim of this study was to describe the demographic, baseline clinical characteristics and early outcomes of a European cohort of liver transplant recipients with SARS-CoV-2 infection.

DESIGN

We conducted an international prospective study across Europe on liver transplant recipients with SARS-CoV-2 infection confirmed by microbiological assay during the first outbreak of COVID-19 pandemic. Baseline characteristics, clinical presentation, management of immunosuppressive therapy and outcomes were collected.

RESULTS

57 patients were included (70% male, median (IQR) age at diagnosis 65 (57-70) years). 21 (37%), 32 (56%) and 21 (37%) patients had one cardiovascular disease, arterial hypertension and diabetes mellitus, respectively. The most common symptoms were fever (79%), cough (55%), dyspnoea (46%), fatigue or myalgia (56%) and GI symptoms (33%). Immunosuppression was reduced in 22 recipients (37%) and discontinued in 4 (7%). With this regard, no impact on outcome was observed. Forty-one (72%) subjects were hospitalised and 11 (19%) developed acute respiratory distress syndrome. Overall, we estimated a case fatality rate of 12% (95% CI 5% to 24%), which increased to 17% (95% CI 7% to 32%) among hospitalised patients. Five out of the seven patients who died had a history of cancer.

CONCLUSION

In this European multicentre prospective study of liver transplant recipients, COVID-19 was associated with an overall and in-hospital fatality rate of 12% (95% CI 5% to 24%) and 17% (95% CI 7% to 32%), respectively. A history of cancer was more frequent in patients with poorer outcome.

Coronavirus disease 2019 in an orthotopic liver transplant recipient living with human immunodeficiency virus

Coronavirus disease 2019 (COVID-19), mediated by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest with flu-like illness and severe pneumonia with acute respiratory distress syndrome (ARDS). Immunocompromised patients merit particular attention as altered host immunity may influence both disease severity and duration of viral shedding as is described with several other ribonucleic acid respiratory viruses. Yet immunocompromised status alone, in the absence of other comorbidities, may not necessarily predict severe illness presentations and poorer clinical outcomes as indicated by recent reports of COVID-19-infected solid organ transplant recipients and people living with human immunodeficiency virus (HIV). Such patients may even be spared the robust inflammatory response that precipitates ARDS associated with COVID-19, complicating the management of iatrogenic immunosuppression in this setting. We present a case of an orthotopic liver transplant recipient with well-controlled HIV who successfully recovered from a mild, flu-like illness attributed to SARS-CoV-2.

Incidence of New-Onset Diabetes and PostTransplant Metabolic Syndrome after Liver Transplantation - A Prospective Study from South India

BACKGROUND AND AIMS

Liver transplantation has become an effective therapy for patients with end-stage liver disease. The risk of new-onset diabetes after transplantation (NODAT) and posttransplant metabolic syndrome (PTMS) is high among patients after liver transplantation. These are thought to be associated with increased risks of graft rejection, infection, cardiovascular disease, and death. Our study aimed to document the incidence of NODAT and PTMS and analyze pre and posttransplant predictive factors for their development in patients undergoing a liver transplant.

METHODS

This was a prospective comparative study on 51 patients who underwent live donor liver transplantation. They were evaluated at baseline, 3 and 6 months after transplantation with fasting glucose, lipids, serum insulin levels, C-peptide, and HbA1C. They were followed up at 5 years to document any cardiovascular events or rejection.

RESULTS

The incidence of preoperative diabetes mellitus (DM) in the study group was 25/51 (49%). The incidence of NODAT was 38.5% (10/26 patients) and PTMS 29% (10/35), respectively. Age (47.7 ± 5.4 vs 41.5 ± 12.7 years), HOMA2 - IR (2.3 ± 1.8 vs 2.1 ± 1.6), serum insulin (16.1 ± 12.0 vs 17.9 ± 14.5), and C-peptide (4.6 ± 0.5 vs 4.8 ± 0.7) were similar at baseline in the NODAT group compared to those who did not develop it. Mean tacrolimus levels were higher in PTMS group (6.8 ± 2.9 vs 5.0. ± 2.0 P value = 0.042). By the end of 5 years, 7 patients expired; 6 due to rejection and one due to cardiovascular disease. Moreover, 2 of these patients had preexisting DM and 2 had NODAT.

CONCLUSIONS

None of the baseline metabolic factors in patients undergoing liver transplant were predictive of the development of NODAT or PTMS. Mean tacrolimus levels were significantly higher in the PTMS group. A 5-year follow-up showed no excess risk of cardiovascular events or rejection in those with preexisting DM or in those who developed NODAT.

The association of pre-operative anaemia with survival after orthotopic liver transplantation

Anaemia is common in patients with end-stage liver disease. Pre-operative anaemia is associated with greater mortality after major surgery. We analysed the association of pre-operative anaemia (World Health Organization classification) with survival and complications after orthotopic liver transplantation using Cox and logistic regression models. We included patients undergoing their first orthotopic liver transplantation between 2004 and 2016. Out of 599 included patients, 455 (76%) were anaemic before transplantation. Pre-operative anaemia was not associated with the survival of 485/599 (81%) patients to 1 year after liver transplantation, OR (95%CI) 1.04 (0.64-1.68), p = 0.88. Pre-operative anaemia was associated with higher rates of intra-operative blood transfusions and acute postoperative kidney injury on multivariable analysis, OR (95%CI) 1.70 (0.82-2.59) and 1.72 (1.11-2.67), respectively, p < 0.001 for both. Postoperative renal replacement therapy was associated with pre-operative anaemia on univariate analysis, OR (95%CI) 1.87 (1.11-3.15), p = 0.018.

Occupational hazard in an immunosuppressed patient

A 60-year-old male liver transplant recipient presented to his local hospital with left-sided partial seizures following a few days of generalised headache. He had undergone transplantation for primary sclerosing cholangitis 4 years earlier and maintained on tacrolimus monotherapy immunosuppression. He had no other comorbidities of note and worked as an arable farmer. At last follow-up, he had been well with preserved graft function and afternoon trough tacrolimus levels of 2-4 ng/mL. Over the preceding 4 weeks, he had been investigated locally for weight loss and a productive cough, where CT of the chest showed calcified mediastinal and hilar lymphadenopathy. Bronchoscopy samples were negative for acid-fast bacilli and he had been empirically treated for assumed community acquired pneumonia. Initial seizure management was with intravenous diazepam and phenytoin. On transfer to our centre, he was noted to be dysarthric with persisting 4/5 left upper limb weakness and nystagmus to all extremes of gaze. Blood tests were significant for mild anaemia (haemoglobin 90 g/L) and elevated C reactive protein (134 mg/L). The peripheral white cell count was 6.6×10⁹/L. Biochemical liver graft function was normal and the 8am trough tacrolimus level was low at 2 ng/mL. CT head revealed bilateral ring enhancing cerebral lesions with surrounding vasogenic oedema but no mass effect. On MRI these exhibited restricted diffusion and marked perilesional oedema, suggestive of infection. Cerebrospinal fluid (CSF) analysis was as follows: white cell count <1/mm³, protein 0.57 g/L (normal range <45 g/L) and glucose 3 mmol/L (paired plasma glucose 4.8 mmol/L). Testing for virological causes via PCR, toxoplasma serology and blood and CSF cultures, including for tuberculosis, were all negative. Whole body positron emission tomography-CT demonstrated uptake in numerous peritoneal and intramuscular lesions as well as right-sided cervical lymphadenopathy, which was sampled with fine needle aspiration. Microscopy revealed a filamentous, beading and branching Gram-positive bacillus that was partially acid-fast, subsequently speciated as Nocardia farcinica.

Antithrombotic management and thrombosis rates in children post-liver transplantation: A case series and literature review

Thrombosis is a major postoperative complication in pediatric liver transplantation. There is marked heterogeneity in prophylactic antithrombotic therapies used, without established guidelines. This review summarizes current worldwide incidence of thrombotic events and compares antithrombotic therapies in children post-liver transplant, with comparison to our institution's experience. Of the twenty-three articles with sufficient detail to compare antithrombotic regimens, the overall incidence of thrombosis ranged from 2.4% to 17.3%. Incidence of HAT ranged from 0% to 28.1%, of HVT from 0% to 4.7%, of PVT from 1.5% to 11.2%, and of IVC thrombosis from 0% to 2.8%. Re-transplantation due to thrombosis ranged from 0% to 4.8%. Prophylactic antithrombotic therapies varied between studies, and bleeding complications were infrequently reported. Since 2010, 96 children underwent 100 liver transplants at our institution with thrombosis incidence comparable to international literature (HAT 6%, PVT 5%, IVC 1%, and HVT 0%). Re-transplantation due to thrombosis occurred in 2% and major bleeding occurred in 10%. The prophylactic antithrombotic therapies used post-liver transplantation in children remain varied. Low rates of thrombosis have been reported with antiplatelet use both with and without anticoagulation. Standard definitions and consistent reporting of bleeding complications are required, in addition to thrombosis rates, so that true risk-benefit assessment of reported regimes can be understood.

Postoperative Risk Factors and Outcome of Patients With Liver Transplantation Who Were Admitted to Pediatric Intensive Care Unit: A 10-Year Single-Center Review in China

INTRODUCTION

The aim of this study was to present our 10-year experience of pediatric intensive care unit (PICU) management with pediatric liver recipients and to understand the importance of close interdisciplinary cooperation in 2 hospitals.

METHODS

A retrospective chart review study was performed according to our hospital's medical records and the pediatric liver transplant database of Renji hospital.

RESULTS

A total of 767 patients received liver transplantation (LT) performed in Renji hospital between October 2006 and December 2016, of which 97 of them were admitted to PICU in our center for various complications developed after transplantation. 8.8% (16/208) and 14.4% (81/559) of patients were transferred to PICU in stages I and II, respectively, and was comparable in the 2 stages (P = .017). The majority of patients was late postoperative children (median 185 post-LT days) in stage I. More patients were transferred to PICU directly in stage II. PICU admitted more younger (median 8.2 months) and early postoperative patients in stage II. The median length of PICU stay was 11.0 (6.0-20.5) days. The median length of mechanical ventilation was 5.0 (0.0-12.0) days. The most frequent complications were pulmonary complications (52 [53.6%] patients), surgical complications (22 [22.7%] patients), sepsis (7 [7.2%]), and other miscellaneous complications (16 [16.5%] patients). The overall 28-day PICU mortality was 25.8% (n = 25) and 64.0% (n = 16) of the deaths happened in the early postoperative period. There was significant difference concerning mortality in children with surgical complications and medical problems (54.5% [12/22] vs 17.3% [13/75], P = .001). Multivariate analysis by regression showed that the pediatric risk of mortality III score was the only independent prognostic factor (P = .031).

CONCLUSIONS

Multiple complications occur in children with LT. Although challenging, interdisciplinary cooperation between different hospitals is an effective mean to enable children to maximize the benefit gained from LT in China.

Median Arcuate Ligament Compression in Orthotopic Liver Transplantation: Results from a Single-Center Analysis and a European Survey Study

Median arcuate ligament compression (MALC) potentially causes arterial complications in orthotopic liver transplantation (OLT). Here we aimed to investigate the incidence of MALC and its impact on clinical outcome after OLT. In addition, we performed an international survey among 52 European liver transplant centers to explore local protocols on the management of these patients. Data of 286 consecutive OLT recipients from a prospective database were analyzed retrospectively (05/2010-07/2017). Preoperative computed-tomography images were evaluated. Celiac axis stenosis due to MALC was found in 34 patients (12%). Intrinsic stenosis was present in 16 (6%) patients. Twenty-six patients (77%) with MALC underwent standard arterial revascularization with median arcuate ligament (MAL)-division. Patients treated for MALC had comparable baseline data and no difference was found in early- and long-term outcome compared to the rest of our cohort. Our survey found heterogeneous strategies regarding diagnosis and treatment of MALC. Only 29% of the centers reported the division of MAL in these patients as routine procedure. Even though there is no consensus on diagnosis and management of MALC among European centers, a surgical division of MAL is feasible and safe and should be considered in OLT recipients with MALC.

Machine perfusion for liver transplantation in the era of marginal organs-New kids on the block

In the face of a critical organ shortage in the Western world, various strategies are employed to expand the donor pool for orthotopic liver transplantation (OLT). Among them is the transplantation of organs from extended criteria donors, a valuable source of liver allografts, however, characterized by potential risks for post-OLT complications and inferior outcomes. In recent years, machine perfusion (MP) of the explanted donor liver as well as regional perfusion techniques has witnessed significant advancements. Here, we aim to discuss different modes of dynamic organ preservation in OLT. These include hypothermic and normothermic MP, hypothermic oxygenated machine perfusion (HOPE), controlled oxygenated rewarming as well as regional perfusion protocols. Over recent years, multiple feasibility trials have demonstrated the clinical prospects of MP. In the context of OLT using organs from extended criteria donors, MP has numerous advantages compared to conventional cold storage, some of which include the preservation and reconditioning of borderline transplantable organs and the viability assessment of high-risk donor allografts. This review aims to address the topic of liver allograft MP, highlighting particularly the current trends in clinical applications and future perspectives. Furthermore, different approaches of liver storage and reconditioning are reviewed in the context of ongoing research.

Hypothyroidism is associated with worse outcomes of hepatocellular carcinoma patients after liver transplantation

Background/Aims

Hypothyroidism has been associated with hepatocellular carcinoma (HCC) incidence; however, the relationship between hypothyroidism and HCC patient outcomes is unclear. We investigated the impact of hypothyroidism on outcomes after liver transplantation for HCC.

Materials and Methods

We retrospectively studied HCC patients transplanted between January 2000 and December 2015. Hypothyroidism was defined as a thyroid‐stimulating hormone (TSH) level continuously greater than 5 mIU/L, a documented history of hypothyroidism, or treatment with thyroid hormone replacement therapy. Multivariate Cox regression was used to assess the impact of hypothyroidism on overall survival (OS) and recurrence‐free survival (RFS) adjusting for potential confounders. Subgroup analyses and interaction tests were conducted to compare the impact of hypothyroidism in different subgroups and assess for possible synergistic effects. Sensitivity analyses were performed among different cohorts to verify the stability of the results.

Results

A total of 343 HCC patients who underwent liver transplantation were included in the analysis. The primary analysis was conducted among 288 patients diagnosed with HCC prior to transplantation. Hypothyroidism was independently associated with worse OS and RFS, as was elevated TSH. The adjusted hazard ratio (AHR) of hypothyroidism was 2.45 (95% confidence interval [CI], 1.44‐4.18) for OS and 5.54 (2.36, 13.01) for RFS. The AHR of TSH for OS was 1.05 (1.02, 1.09) and 1.08 (1.03, 1.13) for RFS. No interaction was found among different subgroups categorized by etiology and comorbidity. The results were stable to sensitivity analyses.

Conclusion

Hypothyroidism is associated with poorer overall and recurrence‐free survival of HCC patients receiving liver transplantation. These results require validation.

Management of anastomotic biliary stricture after liver transplantation: metal versus plastic stent

Background

Post-transplant anastomotic biliary strictures remain refractory to endoscopic therapy in a considerable number of cases. The aim of this meta-analysis was to compare fully-covered self-expandable metal and plastic stents in the management of post-transplant biliary strictures.

Methods

A meta-analysis was performed using a random effects model; results were expressed as odds ratio (OR) and mean standardized difference. The primary outcome was stricture resolution, while recurrence rate after stent placement, treatment time, and safety of the procedure were the secondary outcomes.

Results

Through a systematic literature review until October 2017, we identified 7 studies, of which 4 were randomized controlled trials. Stricture resolution was slightly higher with metal stents, with no statistical difference between the two procedures (OR 1.38, 95% confidence interval [CI] 0.60-3.15; P=0.45) and low heterogeneity (I²=6%). Stricture recurrence showed a non-significant trend in favor of plastic stents (OR 1.82, 95%CI 0.52-6.31, P=0.35). Endoscopic retrograde cholangiopancreatography with placement of metal stents offered a significant improvement in terms of reduced treatment time (mean standardized difference: -3.58 months, 95%CI -6.23 to -0.93; P=0.008), but with more frequent complications, although not significantly so (OR 2.34, 95%CI 0.75-7.25; P=0.14). Sensitivity analysis confirmed all the findings.

Conclusion

Metal stents appear to be a promising tool that can decrease treatment time, although there is still no clear evidence of their superiority over plastic stents in terms of efficacy.

Long-term follow-up of ribavirin-free DAA-based treatment in HCV recurrence after orthotopic liver transplantation

BACKGROUND & AIMS

Excellent efficacy and safety profile of second-generation DAA combinations improved treatment of chronic hepatitis C (HCV) as well as in HCV recurrence after orthotopic liver transplantation (OLT). The need of ribavirin addition is under debate as anaemia and decreased renal function are prevalent in transplant cohorts. The aim of this study was thus to assess safety and long-term efficacy of RBV-free DAA combinations in HCV-recurrent patients after OLT.

PATIENTS & METHODS

A total of 62 OLT recipients (male: 50%/81%; age: 60.7 ± 8.5 years [mean ± SD]; GT - 1: 48, GT - 3: 9, GT - 4: 5; cirrhosis: 34%/55% [7%/21% decompensated], fibrosing cholestatic hepatitis: 1%/2%) received RBV-free treatment with second-generation DAA combinations: sofosbuvir (SOF)/daclatasvir (DCV): 42%/68%, SOF/simeprevir (SMV): 10%/16%, SOF/ledipasvir (LDV): 6%/10% and PrOD: 4%/7%.

RESULTS

Data of at least 96 weeks of FUP after treatment cessation (mean: 120; up to 167 weeks) were analysed. All patients showed on-treatment response. By intention-to-treat (ITT) analysis, SVR12 was 97% (60/62, GT-1a: 11/11 [100%]; 1b: 33/34 [97%]; 1g: 1/1 [100%]; subtype not specified: 2/2 [100%]; GT3a: 9/9 [100%]; GT4: 4/5 [80%]) compared to SVR96 of 89% (55/62). No late relapses occurred. In total, 16 severe adverse events occurred, including two newly diagnosed carcinoma (lung cancer, hepatocellular carcinoma). Six patients died; one at treatment week 24 (HCV-RNA undetectable) and five during treatment-free FUP and after achieving SVR (SVR4: N = 1, SVR12: N = 3, after SVR96: N = 1 respectively). Reasons for death were: multi-organ failure (N = 4), impaired graft function (N = 1) and unknown (N = 1).

CONCLUSION

RBV-free DAA combinations for the treatment of HCV recurrence after OLT are highly efficacious and well tolerated. Our long-term data show that viral eradication is durable but not necessarily translated into beneficial long-term clinical outcome.