Multiple Graft Bile Ducts Do Not Affect the Postoperative Outcomes of Right Lobe Living Donor Liver Transplantation.

Multiple graft duct openings are associated with a high incidence of biliary complications (BCs), and biliary reconstruction for multiple graft bile ducts (BDs) remains a surgical challenge during living donor liver transplantation (LDLT). In particular, biliary reconstruction using "high biliary radicals (HBR)" of recipients for multiple graft BDs has a high probability of BCs. Herein, we analyzed outcomes by retrospectively reviewing 283 patients who underwent right lobe LDLT from January 2013 to September 2019. In total, 112 LDLT procedures using grafts with multiple BDs have been performed under our policies. In recent cases with 2 orifices located on the same hilar plate, we did dunking with a mucosal eversion technique instead of ductoplasty. When 2 orifices are located far apart on different hilar plates, we attempted to perform separate duct-to-duct anastomosis (DDA) using HBR of the recipient instead of hepaticojejunostomy. Among patients with multiple graft BDs, 20 underwent ductoplasty, 50 were treated using dunking with mucosal eversion technique, and 40 underwent separate DDA using HBR (HBR group). The incidence rates of biliary leakage and stricture were 8.9% and 10.7% in the multiple BD group, respectively, congruent with the outcomes of the single BD group. In subgroup analysis, we compared clinical outcomes between the HBR and single BD groups; the incidence of BCs in the HBR group was 15.0%, comparable to that of the single BD group. In conclusion, multiple graft BDs do not negatively impact the BC rate compared with single-graft BD when applying our technique to prevent BCs.

Novel Method for Reconstructing Multiple Graft Bile Ducts During Right Lobe Living Donor Liver Transplant: Dunking With Mucosal Eversion Technique.

BACKGROUND: Multiple graft bile ducts (BDs) and anastomoses have been considered as risk factors for biliary complications after living donor liver transplant (LDLT). Various surgical techniques have been introduced, and most surgeons perform unification ductoplasty for multiple adjacent BDs during LDLT. However, this could cause hemobilia and is difficult to perform when 2 ductal orifices are far apart or show a size discrepancy. METHODS: Here, we introduce our novel reconstruction technique for multiple adjacent graft BDs and discuss its effects on postoperative outcomes compared with ductoplasty. We compared the clinical outcomes of 2 biliary reconstruction techniques by retrospectively reviewing 58 recipients who underwent LDLT with right lobe grafts using these 2 techniques at our institution between January 2013 and September 2018: group 1 (n = 20) received ductoplasty, and group 2 (n = 38) was treated with dunking with mucosal eversion technique. RESULTS: Overall biliary complication rates were 20.0% in group 1 and 10.5% in group 2 (P = .32). Biliary stricture in group 2 was not frequent compared with that in group 1 (7.9% vs 15.0%, P = .398). Moreover, incidence of biliary stricture in group 2 was not different than that in the group using graft with single BD during the same period (P > .624). CONCLUSIONS: Our novel technique could be a useful method for reconstructing adjacent BDs in LDLT and the best alternative to ductoplasty. Moreover, it seems to be a reasonable option when 2 orifices are far apart or show a size discrepancy.

Heterogeneity of Bile Duct Management in the Development of Ischemic Cholangiopathy After Liver Transplantation: Results of a European Liver and Intestine Transplant Association Survey.

BACKGROUND: Surgical factors and direct cytotoxicity of bile salts on cholangiocytes may play a role in the development of ischemic cholangiopathy (IC) after liver transplantation (LTx). There is no validated consensus on how to protect the bile ducts during procurement, static preservation, and LTx. Meanwhile, IC remains the most troublesome complication after LTx. AIM: To characterize bile duct management techniques during the LTx process among European transplant centers in cases of donation after brain death (DBD) and circulatory death (DCD). METHOD: An European Liver and Intestine Transplant Association-European Liver Transplant Registry web survey designed to conceal respondents' personal information was sent to surgeons procuring and/or transplanting livers in Europe. RESULTS: Sixty-five percent of responses came from large transplant centers (>50 procurements/y). In 8% of DBDs and 14% of DCDs the bile duct is not rinsed. In 46% of DBDs and 52% of DCDs surgeons prefer to remove the gallbladder after graft reperfusion. Protocols concerning preservation solutions (nature, pressure, volume) are extremely heterogeneous. In 54% of DBDs and 61% of DCDs an arterial back table pressure perfusion is performed. Steroids (20%-10%), heparin (72%-60%), prostacyclin (3%-7%), and fibrinolytics (4%-11%) are used as donor-protective interventions in DBD and DCD cases, respectively. In 2% of DBD and 6% of DCD cases a hepatic artery reperfusion is performed first. In 4% of DBD and 6% of DCD cases, fibrinolytics are administered through the hepatic artery during the bench and/or implantation. CONCLUSION: This European web survey shows for the first time the heterogeneity in the management of bile ducts during procurement, preservation, and transplantation in Europe. In the context of sharing more marginal liver grafts, an expert meeting must be organized to formulate guidelines to be applied to protect liver grafts against IC.

Effect of Right Posterior Bile Duct Anatomy on Biliary Complications in Patients Undergoing Right Lobe Living Donor Liver Transplant.

OBJECTIVES: Our aim was to evaluate the influence of the localization of right posterior bile duct anatomy relative to portal vein of the donors on posttransplant bile duct complications. MATERIALS AND METHODS: We retrospectively investigated 141 patients who had undergone living donor liver transplant using right hemiliver grafts. The patients were classified based on the pattern of the right posterior bile duct and divided into infraportal and supraportal types. Clinical donor and recipient risk factors and surgical outcomes were compared for their relationship with biliary complications using logistic regression analyses. RESULTS: The 2 groups were similar according to demographic and clinical features. The biliary complication rate was 23.7% (9/38) in the infraportal group and 47.4% (37/78) in the supraportal group (P = .014). An analysis of risk factors for the development of anastomotic bile leak using logistic regression showed that a supraportal right posterior bile duct anatomy was a statistically significant positive predictor, with odds ratio of 18.905 (P = .012; confidence interval, 1.922-185.967). The distance of the right posterior bile duct from confluence was significantly lower in patients with biliary complications than in those without (mean of 7.66 vs 0.40 mm; P = .044). According to receiver operating characteristic analyses, the cut-off point for the length of right bile duct to right posterior bile duct from the hepatic confluence was 9.5 mm regarding presence of complications. CONCLUSIONS: Factors influencing bile duct anastomosis leakage were supraportal-type donor bile duct anatomy and length of the right main bile duct from biliary confluence. Hepatic arterial complications were similarly a risk factor for biliary strictures. Because of the multiple factors leading to complications in living donor liver transplant, it is challenging to group these patients by operative risk; however, establishing risk models may facilitate the prediction of complications.

Biliary Bicarbonate, pH, and Glucose Are Suitable Biomarkers of Biliary Viability During Ex Situ Normothermic Machine Perfusion of Human Donor Livers.

BACKGROUND: Ex situ normothermic machine perfusion (NMP) can be used to assess viability of suboptimal donor livers before implantation. Our aim was to assess the diagnostic accuracy of bile biochemistry for the assessment of bile duct injury (BDI). METHODS: In a preclinical study, 23 human donor livers underwent 6 hours of end-ischemic NMP to determine biomarkers of BDI. Livers were divided into groups with low or high BDI, based on a clinically relevant histological grading system. During NMP, bile was analyzed biochemically and potential biomarkers were correlated with the degree of BDI. Receiver operating characteristics curves were generated to determine optimal cutoff values. For clinical validation, identified biomarkers were subsequently included as viability criteria in a clinical trial (n = 6) to identify transplantable liver grafts with low BDI. RESULTS: Biliary bicarbonate and pH were significantly higher and biliary glucose was significantly lower in livers with low BDI, compared with high BDI. The following cutoff values were associated with low BDI: biliary bicarbonate greater than 18 mmol/L (P = 0.002), biliary pH greater than 7.48 (P = 0.019), biliary glucose less than 16 mmol/L (P = 0.013), and bile/perfusate glucose ratio less than 0.67 (P = 0.013). In the clinical trial, 4 of 6 livers met these criteria and were transplanted, and none developed clinical evidence of posttransplant cholangiopathy. CONCLUSIONS: Biliary bicarbonate, pH, and glucose during ex situ NMP of liver grafts are accurate biomarkers of BDI and can be easily determined point of care, making them suitable for the pretransplant assessment of bile duct viability. This may improve graft selection and decrease the risk of posttransplant cholangiopathy.

Living Donor Liver Transplantation Using Selected Grafts With 2 Bile Ducts Compared With 1 Bile Duct Does Not Impact Patient Outcome.

The outcome after living donor liver transplantation (LDLT) using grafts with multiple bile ducts (BDs) remains unclear. We analyzed 510 patients who received an adult-to-adult right lobe LDLT between 2000 and 2015 and compared outcome parameters of those receiving grafts with 2 BDs (n = 169) with patients receiving grafts with 1 BD (n = 320). Additionally, patients receiving a graft with 3 BDs (n = 21) were analyzed. Demographic variables and disease severity were similar between the groups. Roux-en-Y reconstruction was significantly more common in the 2 BD group (77% versus 38%; P < 0.001) compared with the 1 BD group. No difference was found in biliary complication rates within 1 year after LDLT (1 BD versus 2 BD groups, 18% versus 21%, respectively; P = 0.46). In the 2 BD group, 82/169 (48.5%) patients were reconstructed with 2 anastomoses. The number of anastomoses did not negatively impact biliary complication rates. Recipients' major complication rate (Clavien ≥ 3b) was similar between both groups (1 BD versus 2 BD groups, 21% versus 24%, respectively; P = 0.36). Furthermore, no difference could be found between the 1 BD, the 2 BD, and the 3 BD groups in the frequency of developing biliary complications within 1 year (18%, 21%, 14%, respectively; P = 0.64), BD strictures (15%, 15%, 5%, respectively; P = 0.42), or BD leaks (10%, 11%, 10%, respectively; P = 0.98). In addition, the 1-year (90% versus 91%), 5-year (82% versus 77%), and 10-year (70% versus 66%) graft survival rates as well as the 1-year (92% versus 93%), 5-year (84% versus 80%), and 10-year (75% versus 76%) patient survival rates were comparable between the 1 BD and the 2 BD groups (P = 0.41 and P = 0.54, respectively). In conclusion, this study demonstrates that selected living donor grafts with 2 BDs can be used safely without negatively impacting biliary complication rates and graft or patient survival rates.

Advances in the generation of bioengineered bile ducts.

The generation of bioengineered biliary tissue could contribute to the management of some of the most impactful cholangiopathies associated with liver transplantation, such as biliary atresia or ischemic cholangiopathy. Recent advances in tissue engineering and in vitro cholangiocyte culture have made the achievement of this goal possible. Here we provide an overview of these developments and review the progress towards the generation and transplantation of bioengineered bile ducts. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni and Peter Jansen.

Living-Donor Liver Transplantation With the Use of a Left-Lobe Graft From a Donor With Anomalous Biliary Anatomy in Which B4 Joins the Right Anterior Sectional Duct: A Case Report.

When there is an anatomic anomaly in the biliary tract of the donor for living-donor liver transplantation, the risk of postoperative biliary tract complications increases in both the donor and the recipient. We studied a case of living-donor liver transplantation with a left hepatic lobe graft that had anatomic anomalies, in which the medial segmental branch (B4) joined the anterior segmental branch and the posterior segmental branch formed a common trunk with the lateral segmental branch. A 40-year-old man visited our institution as a candidate organ donor for his mother, who had end-stage liver failure. An anomaly of B4 connecting the anterior segmental branch was suspected on magnetic resonance cholangiopancreatography. On intraoperative cholangiography, confluence of B4 with the anterior segmental branch and connection of the posterior and lateral segmental branches forming a common trunk were confirmed. Accordingly, individual anastomoses of the lateral segmental branch and B4 with the recipient jejunum were planned, and a left-lobe graft was excised. The postoperative recovery was smooth, and the donor was discharged with no complications. Even when an anatomic anomaly is present in the donor bile duct, in urgent cases, accurate evaluation through the use of various modalities may enable living-donor liver transplantation with the use of a graft with an anatomic anomaly.

Efficient recellularisation of decellularised whole-liver grafts using biliary tree and foetal hepatocytes.

A whole-organ regeneration approach, using a decellularised xenogeneic liver as a scaffold for the construction of a transplantable liver was recently reported. Deriving suitable scaffolds was the first step towards clinical application; however, effective recellularisation remains to be achieved. This report presents a strategy for the improvement of the recellularisation process, using novel cell-seeding technique and cell source. We evaluated recellularised liver grafts repopulated through the portal vein or the biliary duct with mice adult hepatocytes or E14.5 foetal hepatocytes. More than 80% of the cells seeded through the biliary tree entered the parenchyma beyond the ductule-lining matrix barrier and distributed throughout the liver lobule. In contrast, about 20% of the cells seeded through the portal tree entered the parenchyma. The gene expression levels of foetal hepatocyte albumin, glucose 6-phosphatase, transferrin, cytokeratin 19, and gamma-glutamyl transpeptidase were increased in three-dimensional cultures in the native liver-derived scaffolds, and the activation of liver detoxification enzymes and formation of biliary duct-like structures were supported. The metabolic functions of liver grafts recellularised with different cell types were similar. These results suggest that biliary tree cell-seeding approach is promising, and that liver progenitor cells represent a good cell source candidate.

Regenerative medicine: Hepatic progenitor cells up their game in the therapeutic stakes.

Bipotential hepatic progenitor cells (HPCs) are recognized as making modest contributions to hepatocyte regeneration, though never credited with major liver repopulation. A new study in mice demonstrates HPCs can make a massive contribution to hepatocyte replacement, suggesting HPCs have the potential to be an effective cell therapy for liver failure.

Hepatic progenitor cells of biliary origin with liver repopulation capacity.

Hepatocytes and cholangiocytes self-renew following liver injury. Following severe injury hepatocytes are increasingly senescent, but whether hepatic progenitor cells (HPCs) then contribute to liver regeneration is unclear. Here, we describe a mouse model where the E3 ubiquitin ligase Mdm2 is inducibly deleted in more than 98% of hepatocytes, causing apoptosis, necrosis and senescence with nearly all hepatocytes expressing p21. This results in florid HPC activation, which is necessary for survival, followed by complete, functional liver reconstitution. HPCs isolated from genetically normal mice, using cell surface markers, were highly expandable and phenotypically stable in vitro. These HPCs were transplanted into adult mouse livers where hepatocyte Mdm2 was repeatedly deleted, creating a non-competitive repopulation assay. Transplanted HPCs contributed significantly to restoration of liver parenchyma, regenerating hepatocytes and biliary epithelia, highlighting their in vivo lineage potency. HPCs are therefore a potential future alternative to hepatocyte or liver transplantation for liver disease.

The bile duct in donation after cardiac death donor liver transplant.

PURPOSE OF REVIEW: This review considers the biliary complications associated with liver transplantation using donation after cardiac death (DCD) donor grafts. RECENT FINDINGS: The increasing use of DCD liver grafts with their increased incidence of biliary complications is discussed. The ethics of this greater use is briefly analysed. Recent animal and human study evidence to support the peribiliary vascular plexus' role in ischaemic cholangiopathy is reviewed. Recent advances in in-vivo and ex-vivo perfusion are explored. In particular, the latest theories regarding perfusion's peribiliary plexus preserving effects and the mechanism by which biliary regeneration may be promoted as a consequence are discussed. SUMMARY: This article explores the need for DCD liver graft use and the associated biliary complications. The current theories regarding the cause of DCD biliary complications are reviewed, as are the current strategies to reduce them.

Bile duct evaluation of potential living liver donors with Gd-EOB-DTPA enhanced MR cholangiography: Single-dose, double dose or half-dose contrast enhanced imaging.

INTRODUCTION: Detailed knowledge of the biliary anatomy is essential to avoid complications in living donor liver transplantation. The aim of this study was to determine the optimal dosage of Gd-EOB-DTPA for contrast-enhanced magnetic resonance cholangiography (ce-MRC) with reference to contrast-enhanced CT cholangiography (ce-CTC). MATERIALS AND METHODS: 30 potential living liver donors (PLLD) underwent both ce-CTC and ce-MRC. Ten candidates each received single, double or half-dose Gd-EOB-DTPA. Ce-MRC images with and without inversion recovery pulses (T1w±IR) were acquired 20-30min after intravenous contrast injection. Image data was quantitatively and qualitatively reviewed by two radiologists based on a on a 5-point scale. Data sets were compared using a Mann-Whitney-U-test or Wilcoxon-rank-sum-test. Kappa values were also calculated. RESULTS: All image series provided sufficient diagnostic information both showing normal biliary anatomy and variant bile ducts. Ce-CTC showed statistically significant better results compared to all ce-MRC data sets. T1w MRC with single dose Gd-EOB-DTPA proved to be superior to half and double dose in subjective and objective evaluation without a statistically significant difference. CONCLUSIONS: Ce-MRC is at any dosage inferior to ce-CTC. As far as preoperative planning of bile duct surgery is focused on the central biliary anatomy, ce-MRC can replace harmful ce-CTC strategies, anyway. Best results were seen with single dose GD-EOB-DTPA on T1w MRC+IR.

Comparison of biomechanical properties of bile duct between pigs and humans for liver xenotransplant.

BACKGROUND: Pigs have been regarded as the preferred source of organs for human xenotransplantation. The aim of the present study was to explore the biomechanical properties of the bile duct in pigs and humans to provide evidence for liver xenotransplantation. MATERIALS AND METHODS: Fresh bile duct specimens obtained from 50 pigs aged 3 to 12 months and five deceased human donors. The diameters and wall thickness of the bile duct were measured using a computer imaging analysis system. The pressure-diameter of bile ducts was tested with biomechanical equipment. The corresponding parameters were calculated: incremental elastic moduli (E(inc)), pressure-strain elastic modulus (E(p)), volume elastic modulus (E(v)), and compliance. RESULTS: The E(inc), E(p), and E(v) of porcine bile duct gradually decreases with age. However, the E(inc), E(p), and E(v) gradually increased after pigs aged 10 months. The E(inc), E(p), and E(v) of pig bile ducts aged 3 to 6, and 11 to 12 months were higher than that of humans aged 20 to 40 years (P < .01). The changes in compliance of the porcine bile duct with age oppose those in elastic modulus. There were no significant differences in the elastic modulus and compliance of the bile duct between pigs aged 7 to 10 months and adult humans (P > .05). CONCLUSIONS: The biomechanical properties of the bile duct of pigs aged 7 to 10 months match that of adult humans. The correlation between age and biomechanical properties of bile ducts in pigs implied that a pig aged 7 to 10 months should be chosen for pig-to-human liver xenotransplantation.

Pancreas-preserving duodenal resections with bile and pancreatic duct replantation for duodenal dystrophy. Two case reports.

CONTEXT: Duodenal dystrophy is a rare disease, characterized by the chronic inflammation of the aberrant pancreatic tissue in the duodenal wall. CASE REPORTS: Two middle-aged men were admitted with upper abdominal pain of several months duration, periodic nausea and vomiting after meals, intermittent jaundice and weight loss. A diagnosis of cystic dystrophy of the vertical part of the duodenum without chronic inflammation of the orthotopic pancreas was established in both cases by multi-detector computed tomography, magnetic resonance imaging and endosonography. Both patients were successfully treated by two modifications of pancreas-preserving duodenal resections with reimplantation of the bile and pancreatic ducts into the neoduodenum. CONCLUSION: These cases are a good example of a pancreas-preserving approach to duodenal dystrophy treatment and can be an alternative to the Whipple procedure in cases of mild changes of the orthotopic gland.

Engraftment of syngeneic and allogeneic endothelial cells, hepatocytes and cholangiocytes into partially hepatectomized rats previously treated with mitomycin C.

BACKGROUND: Pretreatment with retrorsine crosslinks host hepatocyte DNA and prevents proliferation after partial hepatectomy (PH), allowing selective expansion of transplanted progenitors. Shortcomings are length of protocol and carcinogenicity of retrorsine. METHODS: This report describes a rapid liver repopulation protocol using mitomycin C (MMC) to block proliferation of rat hepatocytes in response to PH. One week post-MMC treatment, dipeptidyl peptidase IV negative host rats were given a PH followed by injection of late gestation, newborn, or adult total liver isolates from dipeptidyl peptidase IV positive rats. For allogeneic transplantation, host rats received injections of anti-CD3 antibody before and after PH. RESULTS: Host liver staining 2 to 9 weeks posttransplantation revealed well-defined donor hepatocyte colonies with strong canalicular dipeptidyl peptidase IV activity. At the same cell dose, fetal and newborn isolates produced more colonies than adult liver isolates. Hepatocyte colonies also coexpressed marker proteins characteristic of adult hepatocytes and showed polarized localization of plasma membrane proteins. Host livers contained large clusters of sinusoids lined by dipeptidyl peptidase IV positive endothelial cells coexpressing the endothelial cell marker, RECA-1, but lacked the canalicular marker leucine aminopeptidase. Colonies containing donor hepatocytes, endothelial cells, and bile ducts were also observed. Similar levels of engraftment and expansion were achieved with allogeneic liver cell isolates by using anti-CD3 antibody treatment. CONCLUSIONS: The MMC transplantation model provides a rapid method for engraftment and expansion of hepatocytes, endothelial cells, and cholangiocytes and should be applicable to investigations centering on the role of endothelial cells in liver regeneration and the identification and characterization of putative endothelial, hepatocyte, and cholangiocyte progenitors.

Evaluation of Pringle maneuver during liver resection in a rat model of surgical obstructive jaundice.

Temporary portal triad clamping (Pringle maneuver) during liver resection reduces intraoperative blood loss. A normal liver can safely tolerate normothermic ischemia for up to 60 min. However, its safety in patients with surgical obstructive jaundice (SOJ) is not known. Therefore, we investigated the effect of hepatic ischemia in an experimental rat model of SOJ created by ligating the bile duct. Four groups of rats were created: Group I (sham operation, 10 days later, liver resection); Group II (sham operation, 10 days later, liver resection with 5 min of hepatic ischemia); Group III (bile duct ligation, 10 days later, liver resection); and Group IV (bile duct ligation, 10 days later, liver resection with 5 min of hepatic ischemia). The ischemic injury was assessed by the survival of rats, liver tissue malondialdehyde and total glutathione (markers of free radical injury), serum alanine aminotransferase, aspartate aminotransferase, and liver histology. The results showed decreased survival (47.6% vs. 90% [p = .046]), increased liver tissue malondialdehyde (161 +/- 35 vs. 129 +/- 33 microg/gm liver tissue [p = .05]), and decreased liver tissue total glutathione (565 +/- 169 vs. 1075 +/- 276 nmol/gm liver tissue [p = .05]) in rats with SOJ subjected to hepatic ischemia when compared to nonjaundiced rats. The changes in serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase showed an increasing trend in the SOJ group but were not statistically significant. Ischemic changes in liver histology were seen more often in the SOJ group but were not statistically significant. These data suggest that temporary portal triad clamping in an experimental model of SOJ is detrimental to the outcome of liver resection.

A tissue-engineered artificial bile duct grown to resemble the native bile duct.

The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct.