Impact of Early Reoperation following Living-Donor Liver Transplantation on Graft Survival

Background

The reoperation rate remains high after liver transplantation and the impact of reoperation on graft and recipient outcome is unclear. The aim of our study is to evaluate the impact of early reoperation following living-donor liver transplantation (LDLT) on graft and recipient survival.

Methods

Recipients that underwent LDLT (n = 111) at the University of Tokyo Hospital between January 2007 and December 2012 were divided into two groups, a reoperation group (n = 27) and a non-reoperation group (n = 84), and case-control study was conducted.

Results

Early reoperation was performed in 27 recipients (24.3%). Mean time [standard deviation] from LDLT to reoperation was 10 [9.4] days. Female sex, Child-Pugh class C, Non-HCV etiology, fulminant hepatitis, and the amount of intraoperative fresh frozen plasma administered were identified as possibly predictive variables, among which females and the amount of FFP were identified as independent risk factors for early reoperation by multivariable analysis. The 3-, and 6- month graft survival rates were 88.9% (95%confidential intervals [CI], 70.7–96.4), and 85.2% (95%CI, 66.5–94.3), respectively, in the reoperation group (n = 27), and 95.2% (95%CI, 88.0–98.2), and 92.9% (95%CI, 85.0–96.8), respectively, in the non-reoperation group (n = 84) (the log-rank test, p = 0.31). The 12- and 36- month overall survival rates were 96.3% (95%CI, 77.9–99.5), and 88.3% (95%CI, 69.3–96.2), respectively, in the reoperation group, and 89.3% (95%CI, 80.7–94.3) and 88.0% (95%CI, 79.2–93.4), respectively, in the non-reoperation group (the log-rank test, p = 0.59).

Conclusions

Observed graft survival for the recipients who underwent reoperation was lower compared to those who did not undergo reoperation, though the result was not significantly different. Recipient overall survival with reoperation was comparable to that without reoperation. The present findings enhance the importance of vigilant surveillance for postoperative complication and surgical rescue at an early postoperative stage in the LDLT setting.     

Use of Renal Replacement Therapy May Influence Graft Outcomes following Liver Transplantation for Acute Liver Failure: A Propensity-Score Matched Population-Based Retrospective Cohort Study

Introduction

Acute kidney injury is associated with a poor prognosis in acute liver failure but little is known of outcomes in patients undergoing transplantation for acute liver failure who require renal replacement therapy.

Methods

A retrospective analysis of the United Kingdom Transplant Registry was performed (1 January 2001–31 December 2011) with patient and graft survival determined using Kaplan-Meier methods. Cox proportional hazards models were used together with propensity-score based full matching on renal replacement therapy use.

Results

Three-year patient and graft survival for patients receiving renal replacement therapy were 77.7% and 72.6% compared with 85.1% and 79.4% for those not requiring renal replacement therapy (P<0.001 and P = 0.009 respectively, n = 725). In a Cox proportional hazards model, renal replacement therapy was a predictor of both patient death (hazard ratio (HR) 1.59, 95% CI 1.01–2.50, P = 0.044) but not graft loss (HR 1.39, 95% CI 0.92–2.10, P = 0.114). In groups fully matched on baseline covariates, those not receiving renal replacement therapy with a serum creatinine greater than 175μmol/L had a significantly worse risk of graft failure than those receiving renal replacement therapy.

Conclusion

In patients being transplanted for acute liver failure, use of renal replacement therapy is a strong predictor of patient death and graft loss. Those not receiving renal replacement therapy with an elevated serum creatinine may be at greater risk of early graft failure than those receiving renal replacement therapy. A low threshold for instituting renal replacement therapy may therefore be beneficial.     

Outcomes of Technical Variant Liver Transplantation versus Whole Liver Transplantation for Pediatric Patients: A Meta-Analysis

Objective

To overcome the shortage of appropriate-sized whole liver grafts for children, technical variant liver transplantation has been practiced for decades. We perform a meta-analysis to compare the survival rates and incidence of surgical complications between pediatric whole liver transplantation and technical variant liver transplantation.

Methods

To identify relevant studies up to January 2014, we searched PubMed/Medline, Embase, and Cochrane library databases. The primary outcomes measured were patient and graft survival rates, and the secondary outcomes were the incidence of surgical complications. The outcomes were pooled using a fixed-effects model or random-effects model.

Results

The one-year, three-year, five-year patient survival rates and one-year, three-year graft survival rates were significantly higher in whole liver transplantation than technical variant liver transplantation (OR = 1.62, 1.90, 1.65, 1.78, and 1.62, respectively, p<0.05). There was no significant difference in five-year graft survival rate between the two groups (OR = 1.47, p = 0.10). The incidence of portal vein thrombosis and biliary complications were significantly lower in the whole liver transplantation group (OR = 0.45 and 0.42, both p<0.05). The incidence of hepatic artery thrombosis was comparable between the two groups (OR = 1.21, p = 0.61).

Conclusions

Pediatric whole liver transplantation is associated with better outcomes than technical variant liver transplantation. Continuing efforts should be made to minimize surgical complications to improve the outcomes of technical variant liver transplantation.     

A Transparent, Interactive Software Environment for Communicating Life-Cycle Assessment Results: An Application to Residential Windows

Life-cycle assessments (LCAs) can be used to support the selection of environmentally preferable building materials. But the dominance of the usage phase in the life cycle of building materials represents a special challenge for two reasons. First, many aspects of a building material's usage phase can be context specific. Second, the LCA outcome may rest on a building material's service life, a parameter for which there is typically insufficient information for proper determination. For example, in the selection of a window, important usagephase, context-specific factors that could be determinant include lo-cation/climate, heating-system characteristics (efficiency and fuel), and product durability. A prototype software tool, the Life Cycle Explorer, has been developed that enables decision makers to assess the relative importance of literally dozens of such influential parameters in determining the outcomes of LCA evaluations for building components. The software employed by the Life Cycle Explorer permits extensive layering while maintaining ease of browsing, with the intent of accessibility to both the layperson and the expert. An initial application of the tool addressed residential window selection; the design principles of the software are relevant to the communication phase of a wide variety of LCA and industrial-ecologyrelated modeling projects.     

Evaluation of Argos Telemetry Accuracy in the High-Arctic and Implications for the Estimation of Home-Range Size

Animal tracking through Argos satellite telemetry has enormous potential to test hypotheses in animal behavior, evolutionary ecology, or conservation biology. Yet the applicability of this technique cannot be fully assessed because no clear picture exists as to the conditions influencing the accuracy of Argos locations. Latitude, type of environment, and transmitter movement are among the main candidate factors affecting accuracy. A posteriori data filtering can remove “bad” locations, but again testing is still needed to refine filters. First, we evaluate experimentally the accuracy of Argos locations in a polar terrestrial environment (Nunavut, Canada), with both static and mobile transmitters transported by humans and coupled to GPS transmitters. We report static errors among the lowest published. However, the 68^th error percentiles of mobile transmitters were 1.7 to 3.8 times greater than those of static transmitters. Second, we test how different filtering methods influence the quality of Argos location datasets. Accuracy of location datasets was best improved when filtering in locations of the best classes (LC3 and 2), while the Douglas Argos filter and a homemade speed filter yielded similar performance while retaining more locations. All filters effectively reduced the 68^th error percentiles. Finally, we assess how location error impacted, at six spatial scales, two common estimators of home-range size (a proxy of animal space use behavior synthetizing movements), the minimum convex polygon and the fixed kernel estimator. Location error led to a sometimes dramatic overestimation of home-range size, especially at very local scales. We conclude that Argos telemetry is appropriate to study medium-size terrestrial animals in polar environments, but recommend that location errors are always measured and evaluated against research hypotheses, and that data are always filtered before analysis. How movement speed of transmitters affects location error needs additional research.     

Q-FISH Measurement of Hepatocyte Telomere Lengths in Donor Liver and Graft after Pediatric Living-Donor Liver Transplantation: Donor Age Affects Telomere Length Sustainability

Along with the increasing need for living-donor liver transplantation (LDLT), the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts) of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH). The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r = 0.765, p = 0.0038), demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p = 0.001). Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled.     

Preservation of Human Kidneys for Transplantation: Preliminary Results with a Gambro Perfusion Machine

Twenty-six human cadaveric kidneys have been preserved for up to 36 hours by continuous perfusion with 4·5% albumin solution on a Gambro machine. Of these, 20 kidneys were transplanted, and six were discarded owing to poor perfusion characteristics during storage. Immediate function was obtained with four kidneys, of which two had been preserved for over 30 hours.Satisfactory renal function has been obtained with 17 kidneys, and three kidneys were lost owing to rejection or technical complications. It is our experience that human kidneys can be successfully preserved for up to 36 hours by this technique.     

Application and Evaluation of Interactive 3D PDF for Presenting and Sharing Planning Results for Liver Surgery in Clinical Routine

MethodsWe developed an interactive 3D PDF report document format and implemented a software tool to create these reports automatically. After more than 1000 liver CASP cases that have been reported in clinical routine using our 3D PDF report, an international user survey was carried out online to evaluate the user experience.ResultsOur solution enables the user to interactively explore the anatomical configuration and to have different analyses and various resection proposals displayed within a 3D PDF document covering only a single page that acts more like a software application than like a typical PDF file (“PDF App”). The new 3D PDF report offers many advantages over the previous solutions. According to the results of the online survey, the users have assessed the pragmatic quality (functionality, usability, perspicuity, efficiency) as well as the hedonic quality (attractiveness, novelty) very positively.ConclusionThe usage of 3D PDF for reporting and sharing CASP results is feasible and well accepted by the target audience. Using interactive PDF with embedded 3D models is an enabler for presenting and exchanging complex medical information in an easy and platform-independent way. Medical staff as well as patients can benefit from the possibilities provided by 3D PDF. Our results open the door for a wider use of this new technology, since the basic idea can and should be applied for many medical disciplines and use cases.     

The Association of IL28B Polymorphism and Graft Survival in Patients with Hepatitis C Undergoing Liver Transplantation

Hepatitis C virus (HCV) infection is the leading cause of liver transplantation (LT) in Western countries. Polymorphism in the IL28B gene region has a major impact on the natural history and response to antiviral treatment in HCV. We investigated whether IL28B polymorphism was associated with graft survival in patients with or without HCV undergoing LT. 1,060 adult patients (age >18 years) underwent LT between years 2000 and 2008. Patients with previous LT, living donor LT and patients dying or requiring retransplants within 30 days of LT were excluded. DNA samples of 620 (84%) recipients and 377 (51%) donors were available for genotyping of IL28B rs12979860C>T. Donor IL28B genotypes had no significant differences in graft survival irrespective of HCV status. There was no difference in graft outcome in the non-HCV cohort (n = 293) based on recipient IL28B genotype. In the HCV group (n = 327), recipients with CC or CT genotype had better graft survival compared to TT genotype (62% vs. 48%, p = 0.02). HCV recipients with CC or CT genotype had delayed time to clinically relevant HCV recurrence compared to TT (10.4 vs. 6.7 months, p = 0.002). The beneficial effect of the CC/CT genotype on HCV recurrence and graft survival was independent of antiviral treatment. In conclusion, our study demonstrated that in contrast to donor IL28B genotype recipient IL28B was associated with graft survival and clinically relevant HCV recurrence in HCV infected recipients. No effect of IL28B genotype was manifest in non-HCV LT recipients.     

猪小肠移植术供肠的灌洗和保存

目的探讨围手术期移植小肠灌注和保存的方法。方法切取猪供肠后,采用100 cm左右高度、略加压法,经移植肠血管以15 mL/min左右灌洗速度持续灌注4℃ 3%羟乙基淀粉注射液、4℃生理盐水保存移植肠。移植前对保存的移植小肠进行组织学检查。结果供肠总灌注时间为50.5±10.6 min;冷缺血时间为80.24±24.62min。组织学检查显示移植肠组织学没有明显改变。移植肠存活良好。结论采取上述方法在短时间内可以提供质量良好的供肠。     

Estimation of Sample Size for Reference Interval Studies

The currently used criterion for sample size calculation in a reference interval study is not well stated and leads to imprecise control of the ratio in question. We propose a generalization of the criterion used to determine sufficient sample size in reference interval studies. The generalization allows better estimation of the required sample size when the reference interval estimation will be using a power transformation or is nonparametric. Bootstrap methods are presented to estimate sample sizes required by the generalized criterion. Simulation of several distributions both symmetric and positively skewed is presented to compare the sample size estimators. The new method is illustrated on a data set of plasma glucose values from a 50‐g oral glucose tolerance test. It is seen that the sample sizes calculated from the generalized criterion leads to more reliable control of the desired ratio.     

ALLocator: An Interactive Web Platform for the Analysis of Metabolomic LC-ESI-MS Datasets,Enabling Semi-Automated,User-Revised Compound Annotation and Mass Isotopomer Ratio Analysis

Adduct formation, fragmentation events and matrix effects impose special challenges to the identification and quantitation of metabolites in LC-ESI-MS datasets. An important step in compound identification is the deconvolution of mass signals. During this processing step, peaks representing adducts, fragments, and isotopologues of the same analyte are allocated to a distinct group, in order to separate peaks from coeluting compounds. From these peak groups, neutral masses and pseudo spectra are derived and used for metabolite identification via mass decomposition and database matching. Quantitation of metabolites is hampered by matrix effects and nonlinear responses in LC-ESI-MS measurements. A common approach to correct for these effects is the addition of a U-¹³C-labeled internal standard and the calculation of mass isotopomer ratios for each metabolite. Here we present a new web-platform for the analysis of LC-ESI-MS experiments. ALLocator covers the workflow from raw data processing to metabolite identification and mass isotopomer ratio analysis. The integrated processing pipeline for spectra deconvolution “ALLocatorSD” generates pseudo spectra and automatically identifies peaks emerging from the U-¹³C-labeled internal standard. Information from the latter improves mass decomposition and annotation of neutral losses. ALLocator provides an interactive and dynamic interface to explore and enhance the results in depth. Pseudo spectra of identified metabolites can be stored in user- and method-specific reference lists that can be applied on succeeding datasets. The potential of the software is exemplified in an experiment, in which abundance fold-changes of metabolites of the l-arginine biosynthesis in C. glutamicum type strain ATCC 13032 and l-arginine producing strain ATCC 21831 are compared. Furthermore, the capability for detection and annotation of uncommon large neutral losses is shown by the identification of (γ-)glutamyl dipeptides in the same strains. ALLocator is available online at: https://allocator.cebitec.uni-bielefeld.de. A login is required, but freely available.     

Salvage Liver Transplantation for Recurrent Hepatocellular Carcinoma after Liver Resection: Retrospective Study of the Milan and Hangzhou Criteria

Background

Salvage liver transplantation (SLT) has recently been proposed for recurrent hepatocellular carcinoma after liver resection; however, criteria for candidate assessment in SLT have not been thoroughly evaluated.

Methods and Findings

We retrospectively analyzed outcomes and factors affecting survival of 53 recipients who received SLT in the Liver Transplantation Center, The First Affiliated Hospital of Zhejiang University between 2004 and 2012. Thirty recipients fulfilled the Hangzhou criteria, of which 16 also fulfilled the Milan criteria, while the remaining 23 exceeded both criteria. The 1-year, 3-year and 5-year overall survival rates and tumor-free survival rates were both superior in patients fulfilling Milan or Hangzhou criteria compared with those exceeding the criteria. For recipients outside Milan criteria but within Hangzhou criteria, the 1-year, 3-year overall survival rates were 70.1%, 70.1%, similar to recipients within Milan criteria, with the 1-year, 3-year and 5-year overall survival of 93.8%%, 62.1% and 62.1% (P = 0.586). The tumor-free survival rates were also similar between these two subgroups, with 51.9% and 51.9% vs. 85.6%, 85.6% and 64.2% during the same time interval, respectively (P = 0.054). Cox regression analysis identified Hangzhou criteria (within vs. outside, hazard ratio (HR) 0.376) and diameter of the largest tumor (HR 3.523) to be independent predictors for overall survival. The only predictor for tumor-free survival was diameter of the largest tumor (HR 22.289).

Conclusions

Hangzhou criteria safely expanded the candidate pool and are feasible in assessment of candidates for SLT. This is helpful in donor liver allocation in transplant practice.     

Aspergillosis of Biliary Tract After Liver Transplantation: A Case Report

We reported a case of aspergillosis presented as cholangitis in a patient after liver transplantation, even with prophylactic use of fluconazole. The patient had multiple predisposing factors, such as leukocytopenia, immunosuppressive drug therapy. He died 2 days after an exploratory laparotomy was carried out. The histopathologic finding of biopsy specimen from biliary tract was positive for Aspergillus. And the pathogen was identified as Aspergillus flavus by mycological culture and PCR. The patient was confirmed as a case of Aspergillosis of biliary tract that was responded poorly to fluconazole. This indicated that azole should have been switched to more effective antifungal agents at earlier stage when the patients responded poorly to the original treatment.     

Liver Transplantation in Man—II,a Report of two Orthotopic Liver Transplants in Adult Recipients

Two patients with primary hepatic malignancy were treated by hepatectomy and orthotopic liver transplantation. In both cases the donor liver was infused with cold solutions and kept chilled without continuous perfusion. There was immediate satisfactory hepatic function in both transplants.The first patient died after 11 weeks from overwhelming bacterial and fungal infections probably secondary to hepatic infarction due to thrombosis of the recipient hepatic artery. The thrombus occurred at the site of the arterial clamp. In an attempt to control the growth before transplantation, the patient had been treated with large doses of chlorambucil, which resulted in extreme marrow depression and septicaemia.The second patient developed cholestatic jaundice during the second and third weeks after transplantation, with histological evidence of mild rejection, which was controlled by increasing the dose of immunosuppressive agents. He is now well, having returned to work six weeks after the operation.Though the first patient showed no evidence of rejection, it is concluded that patients receiving liver allografts should receive immunosuppressive therapy.     

Development of a New Technique for Reconstruction of Hepatic Artery during Liver Transplantation in Sprague-Dawley Rat

Background

Sleeve anastomosis is the most common technique used to rearterialize orthotopic liver transplants (OLT). However, this technique has a number of disadvantages, including difficulty of performance of the technique visually unaided. We herein describe a novel rearterialized OLT model in the rat.

Materials and Methods

Forty-six male Sprague Dawley rats (300–400 g) were used as donors and recipients. Based on Kamada’s cuff technique, the new model involved performing a modified “sleeve” anastomosis between the celiac trunk of the donor and common hepatic artery of the recipient to reconstruct blood flow to the hepatic artery. An additional ten male Sprague Dawley rats underwent liver transplantation without artery reconstruction. Liver grafts were retrieved from the two groups and histological examination was performed following surgery.

Results

Total mean operating times were ~42 minutes for the donor liver extraction and 57 minutes for the recipient transplantation. Graft preparation took an additional 15 minutes and the time to fix the arterial bracket was ~3 minutes. During transplantation, the anhepatic phase lasted 18 ± 2.5 min and the artery reconstruction only required ~3 minutes. The patency rate was 94.44% and the 4-week survival rate was 90%. Histology indicated obvious fibrosis in the liver grafts without artery reconstruction, while normal histology was observed in the arterialized graft.

Conclusions

This new method allows for the surgical procedure to be performed visually unaided with good survival and patency rates and represents an alternative model investigating OLT in rats.