Recent advances in liver transplantation

High and Low Frequency Domino Liver Transplantation Centers Demonstrate Similar Performance Outcomes

INTRODUCTION

A Domino Liver Transplant (DLT) is a successfully validated surgical option for a subset of patients awaiting liver transplant. Increased utilization of DLTs could increase the donor organ pool. However, DLTs occur primarily at a small number of high volume centers, and are rarely performed at lower volume transplant centers. This study compares DLT recipient performance outcomes between high frequency DLT centers and low frequency DLT centers.

METHODS

The UNOS/OPTN STAR database was queried for DLTs performed at transplant centers between 1996-2018. 193 patients were identified and categorized into high (>5 DLTs) or low (≤5 DLTs) frequency centers. Our primary endpoint was allograft survival. Our secondary endpoints were graft status at last follow up and mortality secondary to cardiac, renal, or respiratory failure.

RESULTS

Overall median allograft survival between high and low volume DLT centers was similar (48.2 months versus 42.7 months, P >0.314). The one-year (82% versus 76%), three-year (57% versus 56%), and five-year (45% versus 43%) survival percentages were also similar between the high and low volume DLT centers respectively. Overall mortality from cardiac (high 4% versus low 1.7%), renal (high 0.8% versus low 1.7%), or respiratory failure (high 0.8% versus low 1.7%) was similarly low in both groups.

CONCLUSION

Low volume and high volume DLT centers are associated with similar outcomes of allograft survival and mortality. DLTs should be utilized more frequently, when the criteria are met, including in centers with limited experience, to expand the donor pool, decrease time on the waitlist, and improve overall survival.

DISCLOSURES

There are no disclosures. The authors report no proprietary or commercial interest in any product mentioned or concept discussed in this article.

Post liver transplant recurrent and de novo viral infections

Survival following liver transplantation has changed dramatically owing to improvement in surgical techniques, peri-operative care and optimal immunosuppressive therapy. Post-Liver transplant (LT) de novo or recurrent viral infection continues to cause major allograft dysfunction, leading to poor graft and patient survival in untreated patients. Availability of highly effective antiviral drugs has significantly improved post-LT survival. Patients transplanted for chronic hepatitis B infection should receive life-long nucleos(t)ide analogues, with or without HBIg for effective viral control. Patients with chronic hepatitis C should be commenced on directly acting antiviral (DAA) drugs prior to transplantation. DAA therapy for post-LT recurrent hepatitis C infection is associated with close to 100% sustained virological response (SVR), irrespective of genotype. De novo chronic Hepatitis E infection is an increasingly recognised cause of allograft dysfunction in LT recipients. Untreated chronic HEV infection of the graft may lead to liver fibrosis and allograft failure. CMV and EBV can reactivate leading to systemic illness following liver transplantation. With COVID-19 pandemic, post-transplant patients are at risk of SARS-Co-V2 infection. Majority of the LT recipients require hospitalization, and the mortality in this population is around 20%. Early recognition of allograft dysfunction and identification of viral aetiology is essential in the management of post-LT de novo or recurrent infections. Optimising immunosuppression is an important step in reducing the severity of allograft damage in the treatment of post-transplant viral infections. Viral clearance or control can be achieved by early initiation of high potency antiviral therapy.

Post Liver Transplantation Survival and Related Prognostic Factors among Adult Recipients in Tehran Liver Transplant Center; 2002-2019

BACKGROUND

Liver transplantation is a standard treatment for patients with end-stage liver disease (ESLD). However, with increasing demand for this treatment and limited resources, it is available only to patients who are more likely to survive. The primary aim was to determine prognostic factors for survival.

METHODS

We collected data from 597 adult patients with ESLD, who received a single organ and initial orthotopic liver transplantation (OLT) in our center between 20 March 2008 and 20 March 2018. In this historical cohort study, univariate and multiple Cox model were used to determine prognostic factors of survival after transplantation.

RESULTS

After a median follow-up of 825 (0-3889) days, 111 (19%) patients died. Survival rates were 88%, 85%, 82% and 79% at 90 days, 1 year, 3 years, and 5 years, respectively. Older patients (HR = 1.27; 95% CI: 1.01-1.59), presence of pre-OLT ascites (HR = 2.03; 95% CI: 1.16-3.57), pre-OLT hospitalization (HR = 1.88; 95% CI:1.02-3.46), longer operative time (HR = 1.006; 95% CI: 1.004-1.008), post-OLT dialysis (HR = 3.51; 95% CI: 2.07-5.94), cancer (HR = 2.69; 95% CI: 1.23-5.89) and AID (HR = 2.04; 95% CI: 1.17-3.56) as underlying disease versus hepatitis, and higher pre-OLT creatinine (HR = 1.67; 95% CI: 1.10-2.52) were associated with decreased survival.

CONCLUSION

In this center, not only are survival outcomes excellent, but also younger patients, cases with better pre-operative health conditions, and those without complications after OLT have superior survival.

1000 consecutive liver transplants. Descriptive analysis and evolution of a single center

Between 1991 and 2013, 1,000 liver transplantations were performed at Virgen del Rocio Hospital (Seville, Spain). A retrospective study was conducted, analyzing the characteristics of recipients and donors, indications, surgical technique, complications and survival in 2 different stages (1991-2002 vs. 2003-2013) coinciding with the implementation of the MELD scale as a prioritization model. The most frequent indication were of hepatopathy of hepatocellular origin in 48.8%. There was a significant increase in the indications for hepatocarcinoma (8.6% and 24.1% P=0.03), and the rate of retransplantation (5.9% vs 9.6%, P=0.04). There was a change in the age of donation, going from 27.7 years in 1990 to 62.9 years in 2012 (P=0.001). The percentage of patients who did not require blood transfusion doubled (6.16 vs. 14.31%, P=.001). Survival of all patients after one, 5 and 10 years was 77, 63.5 and 51.3%, respectively.

Early-Onset Pneumonia After Liver Transplant: Microbial Causes, Risk Factors, and Outcomes, Mansoura University, Egypt, Experience

OBJECTIVES

Pneumonia has a negative effect on the outcome of liver transplant. Our aim was to analyze early-onset pneumonia that developed within the first month after transplant.

MATERIALS AND METHODS

This prospective single-center study included 56 adult living-donor liver transplant recipients; those who developed early-onset pneumonia based on clinical and radiologic criteria were investigated as to causative pathogens and then followed up and compared with other recipients without pneumonia to illustrate risk factors, outcomes, and related mortality of posttransplant pneumonia.

RESULTS

Twelve patients (21.4%) developed early-onset pneumonia with mortality rate of 75% (9 of 12). Sixteen pathogens were isolated; extended spectrum beta-lactamase producing Enterobacteriaceae were the most common (31.2%) followed by carbapenem-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (18.8%). Fungi were isolated in 3 cases that were also coinfected with bacteria. Diabetes mellitus (P = .042), liberal postoperative fluid therapy (P = .028), prolonged posttransplant intensive care unit stay (P = .01), atelectasis grade ≥ 2 (P ≤ .001), and calcineurin inhibitor-induced neurotoxicity (P = .04) were risk factors for early posttransplant pneumonia.

CONCLUSIONS

Pneumonia is the leading cause of early mortality after liver transplant. The emergence of multidrug-resistant bacteria is major issue associated with a high rate of treatment failure.

Analysis of the First 1000 Liver Transplants in Virgen del Rocío Hospital

The goal of this work has been to analyze the first 1000 liver transplantations (LTs) performed in the Virgen del Rocío Hospital of Seville and to evaluate the changes in that time. We included 916 patients who had 1000 LTs. We distinguish 2 stages in the follow-up: the first stage, between 1990 and 2002, and the second, from 2003 to 2013 (Model for End-stage Liver Disease [MELD] stage). We analyzed recipient features, LT indications, donation criteria, surgical technique, complications, and survival both for patients and grafts. The median age of recipients was 53.50 ± 46.49 years old, with a noticeable increase after 2000. There were 3 times as many men as women. The most frequent indications for LT were hepatocellular disease (48.8%), followed by hepatocarcinoma (17.8%), retransplantation (8.1%), and cholestatic diseases (3.6%). Donors of Andalusian centers accounted for 88.2% of LTs, and 8.3% of LTs presented some arterial or venous complication. Biliary complications occurred in 15.6%. Patient survival at 1, 5, and 10 years was 77%, 63.5%, and 51.3%, respectively. In conclusion, some of the factors that negatively influenced survival of the patient were stage of the LT, hepatitis C virus-positive recipient, emergency cases, hepatocarcinoma, high consumption of blood products, and second transplantations.

Impact of Long-Term Immunosuppressive Therapy on Psychosocial and Physical Well Being in Liver Transplant Recipients

To achieve the fullest potential of transplantation, continuing concern for the recipients' quality of life must be a part of the process. Database records of patients who are currently alive and received transplants between 1982 and 1991 were retrospectively analyzed. Recipients were contacted and asked to answer a quality-of-life questionnaire. Of 105 liver transplant recipients, 51 died within 10 years after transplantation; 47 were contacted. Posttransplant complications included hypertension (64%), posttransplant diabetes mellitus (17%), osteopenia (40%), osteoporosis (26%), and heart disease (17%). Most recipients reported all aspects of their life to be average, if not better than their age-matched peers. Although most recipients complained about side effects of immunosuppressive agents, they were all happy to be alive and agreed that their quality of life showed an impressive favorable change to a level exceeding that of the general population. These results suggest that liver transplantation not only improved survival but also quality of life.

Selective intestinal decontamination for the prevention of early bacterial infections after liver transplantation

Bacterial infection in the first month after liver transplantation is a frequent complication that poses a serious risk for liver transplant recipients as contributes substantially to increased length of hospitalization and hospital costs being a leading cause of death in this period. Most of these infections are caused by gram-negative bacilli, although gram-positive infections, especially Enterococcus sp. constitute an emerging infectious problem. This high rate of early postoperative infections after liver transplant has generated interest in exploring various prophylactic approaches to surmount this problem. One of these approaches is selective intestinal decontamination (SID). SID is a prophylactic strategy that consists of the administration of antimicrobials with limited anaerobicidal activity in order to reduce the burden of aerobic gram-negative bacteria and/or yeast in the intestinal tract and so prevent infections caused by these organisms. The majority of studies carried out to date have found SID to be effective in the reduction of gram-negative infection, but the effect on overall infection is limited due to a higher number of infection episodes by pathogenic enterococci and coagulase-negative staphylococci. However, difficulties in general extrapolation of the favorable results obtained in specific studies together with the potential risk of selection of multirresistant microorganisms has conditioned controversy about the routinely application of these strategies in liver transplant recipients.

Renal function improvement in liver transplant recipients after early everolimus conversion: A clinical practice cohort study in Spain

A national, multicenter, retrospective study was conducted to assess the results obtained for liver transplant recipients with conversion to everolimus in daily practice. The study included 477 recipients (481 transplantations). Indications for conversion to everolimus were renal dysfunction (32.6% of cases), hepatocellular carcinoma (HCC; 30.2%; prophylactic treatment for 68.9%), and de novo malignancy (29.7%). The median time from transplantation to conversion to everolimus was 68.7 months for de novo malignancy, 23.8 months for renal dysfunction, and 7.1 months for HCC and other indications. During the first year of treatment, mean everolimus trough levels were 5.4 (standard deviation [SD], 2.7) ng/mL and doses remained stable (1.5 mg/day) from the first month after conversion. An everolimus monotherapy regimen was followed by 28.5% of patients at 12 months. Patients with renal dysfunction showed a glomerular filtration rate (4-variable Modification of Diet in Renal Disease) increase of 10.9 mL (baseline mean, 45.8 [SD, 25.3] versus 57.6 [SD, 27.6] mL/minute/1.73 m(2) ) at 3 months after everolimus initiation (P < 0.001), and 6.8 mL at 12 months. Improvement in renal function was higher in patients with early conversion (<1 year). Adverse events were the primary reason for discontinuation in 11.2% of cases. The probability of survival at 3 years after conversion to everolimus was 83.0%, 71.1%, and 59.5% for the renal dysfunction, de novo malignancy, and HCC groups, respectively. Everolimus is a viable option for the treatment of renal dysfunction, and earlier conversion is associated with better recovery of renal function. Prospective studies are needed to confirm advantages in patients with malignancy.

Cellularized biosynthetic microhydrogel polymers for intravascular liver tissue regeneration therapy

INTRODUCTION

The liver is the natural microenvironment for hepatocytes transplantation but unfortunately engraftment efficiency is low. Cell-laden microhydrogels made of fibrinogen attached to poly(ethylene glycol) (PEG)-diacrylate side chains, were used as a cell carrier, for intravascular transplantation. This approach may reduce shear stress and immediate immunological pressure after intravascular transplantation and provide biomatrix for environmental support.

AIMS

In vitro assessment of HuH-7 viability and function after polymerization within PEGylated fibrinogen-hydrogel. In vivo assessment of intraportal transplantation of cell-laden microhydrogels with rat adult parenchymal cells.

METHODS

(1) In vitro assessment of HuH-7 cell viability and function, after cell-laden hydrogel (hydrogel volume 30 μL) fabrication, by propidium iodide (PI)/fluorescein diacetate (FDA), and MTT assays, albumin concentration and CYP1A activity. (2) Fabrication of cell-laden microhydrogels and their intraportal transplantion. Engraftment efficiency in vivo was evaluated by real-time qPCR of Y chromosome (SRY gene) and histology.

RESULTS

The viability of cells in hydrogels in culture was comparable to viability of not embedded cells during the first 48 h. However, the viability of cells in hydrogels was reduced after 72 h compared with not embedded cells. Activity of CYP1A in hydrogel was comparable to that of not embedded cells (4.33±1 pmole/μg DNA/4 h vs. 5.13±1 pmole/μg DNA/4 h, respectively). Albumin concentration increased at day 3 in hydrogels to 1.4±0.6 μg/10(4)/24 h and was greater to that of free cells, 0.3±0.1 μg/10(4)/24 h. Cell-laden microhydrogels at a size of 150-150-600 μm (6×10(6) cells/rat) showed better engraftment efficiency at 21 days post-transplantation, compared with isolated cell transplantation (54.6%±5% vs. 1.8%±1.2%, p<0.001).

CONCLUSIONS

The in vitro HuH-7 viability and function after polymerization in PEGylated fibrinogen hydrogel was comparable to cells without the hydrogel. Long-term survival and engraftment efficiency of intravascular transplanted adult hepatocytes is much better in within cell-laden microhydrogels compared with isolated cells. The overall efficiency of the procedure needs to be improved.

Early introduction of everolimus immunosuppressive regimen in liver transplantation with extra-anatomic aortoiliac-hepatic arterial graft anastomosis

Liver transplantation is the treatment of choice for patients with acute and chronic end-stage liver disease, when no other medical treatment is possible. Despite high rates of 1- to 5-year survival, long-term adverse effects of immunosuppressant agents remain of major concern. Current research and clinical efforts are made to develop immunosuppressant agents that minimize adverse effects along with a low rate of graft rejection. Tailoring immunosuppressive therapy to individual patients by the use of proliferation signal inhibitors seems to be the best way to minimize toxicity and increase efficacy. Recently everolimus has been introduced in clinical practice; among its adverse effects an increased incidence of arterial graft thrombosis in renal transplants, vascular anastomosis leakage, impaired wound healing, and thrombotic microangiopathy have been reported. We present the case of a 54-year-old patient submitted to liver transplantation for end-stage liver disease treated by an extra-anatomic aortoiliac-hepatic arterial graft anastomosis and early postoperative introduction of everolimus for acute renal failure. Postoperative period was characterized by two abdominal collections and reactivation of cytomegalovirus infection that were treated by percutaneous drainage and antiviral therapy, respectively; the patient is well after 8-month followup with patency of the arterial conduit and no leakage.

Antibody induction versus placebo, no induction, or another type of antibody induction for liver transplant recipients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell antibody induction for preventing rejection after liver transplantation.

OBJECTIVES

To assess the benefits and harms of immunosuppressive T-cell specific antibody induction compared with placebo, no induction, or another type of T-cell specific antibody induction for prevention of acute rejection in liver transplant recipients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) until September 2013.

SELECTION CRITERIA

Randomised clinical trials assessing immunosuppression with T-cell specific antibody induction compared with placebo, no induction, or another type of antibody induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should have received the same maintenance immunosuppressive therapy. We planned to include trials with all of the different types of T-cell specific antibodies that are or have been used for induction (ie., polyclonal antibodies (rabbit of horse antithymocyte globulin (ATG), or antilymphocyte globulin (ALG)), monoclonal antibodies (muromonab-CD3, anti-CD2, or alemtuzumab), and interleukin-2 receptor antagonists (daclizumab, basiliximab, BT563, or Lo-Tact-1)).

DATA COLLECTION AND ANALYSIS

We used RevMan analysis for statistical analysis of dichotomous data with risk ratio (RR) and of continuous data with mean difference (MD), both with 95% confidence intervals (CIs). We assessed the risk of systematic errors (bias) using bias risk domains with definitions. We used trial sequential analysis to control for random errors (play of chance). We presented outcome results in a summary of findings table.

MAIN RESULTS

We included 19 randomised clinical trials with a total of 2067 liver transplant recipients. All 19 trials were with high risk of bias. Of the 19 trials, 16 trials were two-arm trials, and three trials were three-arm trials. Hence, we found 25 trial comparisons with antibody induction agents: interleukin-2 receptor antagonist (IL-2 RA) versus no induction (10 trials with 1454 participants); monoclonal antibody versus no induction (five trials with 398 participants); polyclonal antibody versus no induction (three trials with 145 participants); IL-2 RA versus monoclonal antibody (one trial with 87 participants); and IL-2 RA versus polyclonal antibody (two trials with 112 participants). Thus, we were able to compare T-cell specific antibody induction versus no induction (17 trials with a total of 1955 participants). Overall, no difference in mortality (RR 0.91; 95% CI 0.64 to 1.28; low-quality of evidence), graft loss including death (RR 0.92; 95% CI 0.71 to 1.19; low-quality of evidence), and adverse events ((RR 0.97; 95% CI 0.93 to 1.02; low-quality evidence) outcomes was observed between any kind of T-cell specific antibody induction compared with no induction when the T-cell specific antibody induction agents were analysed together or separately. Acute rejection seemed to be reduced when any kind of T-cell specific antibody induction was compared with no induction (RR 0.85, 95% CI 0.75 to 0.96; moderate-quality evidence), and when trial sequential analysis was applied, the trial sequential monitoring boundary for benefit was crossed before the required information size was obtained. Furthermore, serum creatinine was statistically significantly higher when T-cell specific antibody induction was compared with no induction (MD 3.77 μmol/L, 95% CI 0.33 to 7.21; low-quality evidence), as well as when polyclonal T-cell specific antibody induction was compared with no induction, but this small difference was not clinically significant. We found no statistically significant differences for any of the remaining predefined outcomes - infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension - when the T-cell specific antibody induction agents were analysed together or separately. Limited data were available for meta-analysis on drug-specific adverse events such as haematological adverse events for antithymocyte globulin. No data were found on quality of life.When T-cell specific antibody induction agents were compared with another type of antibody induction, no statistically significant differences were found for mortality, graft loss, and acute rejection for the separate analyses. When interleukin-2 receptor antagonists were compared with polyclonal T-cell specific antibody induction, drug-related adverse events were less common among participants treated with interleukin-2 receptor antagonists (RR 0.23, 95% CI 0.09 to 0.63; low-quality evidence), but this was caused by the results from one trial, and trial sequential analysis could not exclude random errors. We found no statistically significant differences for any of the remaining predefined outcomes: infection, cytomegalovirus infection, hepatitis C recurrence, malignancy, post-transplant lymphoproliferative disease, renal failure requiring dialysis, hyperlipidaemia, diabetes mellitus, and hypertension. No data were found on quality of life.

AUTHORS' CONCLUSIONS

The effects of T-cell antibody induction remain uncertain because of the high risk of bias of the randomised clinical trials, the small number of randomised clinical trials reported, and the limited numbers of participants and outcomes in the trials. T-cell specific antibody induction seems to reduce acute rejection when compared with no induction. No other clear benefits or harms were associated with the use of any kind of T-cell specific antibody induction compared with no induction, or when compared with another type of T-cell specific antibody. Hence, more randomised clinical trials are needed to assess the benefits and harms of T-cell specific antibody induction compared with placebo, and compared with another type of antibody, for prevention of rejection in liver transplant recipients. Such trials ought to be conducted with low risks of systematic error (bias) and low risk of random error (play of chance).

Antibody induction versus corticosteroid induction for liver transplant recipients

BACKGROUND

Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell specific antibody induction compared with corticosteroid induction of immunosuppression after liver transplantation.

OBJECTIVES

To assess the benefits and harms of T-cell specific antibody induction versus corticosteroid induction for prevention of acute rejection in liver transplant recipients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 30 September 2013 together with reference checking, citation searching, contact with trial authors and pharmaceutical companies to identify additional trials.

SELECTION CRITERIA

We included all randomised clinical trials assessing immunosuppression with T-cell specific antibody induction versus corticosteroid induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should have received the same maintenance immunosuppressive therapy.

DATA COLLECTION AND ANALYSIS

We used RevMan for statistical analysis of dichotomous data with risk ratio (RR) and of continuous data with mean difference (MD), both with 95% confidence intervals (CIs). We assessed risk of systematic errors (bias) using bias risk domains with definitions. We used trial sequential analysis to control for random errors (play of chance).

MAIN RESULTS

We included 10 randomised trials with a total of 1589 liver transplant recipients, which studied the use of T-cell specific antibody induction versus corticosteroid induction. All trials were with high risk of bias. We compared any kind of T-cell specific antibody induction versus corticosteroid induction in 10 trials with 1589 participants, including interleukin-2 receptor antagonist induction versus corticosteroid induction in nine trials with 1470 participants, and polyclonal T-cell specific antibody induction versus corticosteroid induction in one trial with 119 participants.Our analyses showed no significant differences regarding mortality (RR 1.01, 95% CI 0.72 to 1.43), graft loss (RR 1.12, 95% CI 0.82 to 1.53) and acute rejection (RR 0.84, 95% CI 0.70 to 1.00), infection (RR 0.96, 95% CI 0.85 to 1.09), hepatitis C virus recurrence (RR 0.89, 95% CI 0.79 to 1.00), malignancy (RR 0.59, 95% CI 0.13 to 2.73), and post-transplantation lymphoproliferative disorder (RR 1.00, 95% CI 0.07 to 15.38) when any kind of T-cell specific antibody induction was compared with corticosteroid induction (all low-quality evidence). Cytomegalovirus infection was less frequent in patients receiving any kind of T-cell specific antibody induction compared with corticosteroid induction (RR 0.50, 95% CI 0.33 to 0.75; low-quality evidence). This was also observed when interleukin-2 receptor antagonist induction was compared with corticosteroid induction (RR 0.55, 95% CI 0.37 to 0.83; low-quality evidence), and when polyclonal T-cell specific antibody induction was compared with corticosteroid induction (RR 0.21, 95% CI 0.06 to 0.70; low-quality evidence). However, when trial sequential analysis regarding cytomegalovirus infection was applied, the required information size was not reached. Furthermore, diabetes mellitus occurred less frequently when T-cell specific antibody induction was compared with corticosteroid induction (RR 0.45, 95% CI 0.34 to 0.60; low-quality evidence), when interleukin-2 receptor antagonist induction was compared with corticosteroid induction (RR 0.45, 95% CI 0.35 to 0.61; low-quality evidence), and when polyclonal T-cell specific antibody induction was compared with corticosteroid induction (RR 0.12, 95% CI 0.02 to 0.95; low-quality evidence). When trial sequential analysis was applied, the trial sequential monitoring boundary for benefit was crossed. We found no subgroup differences for type of interleukin-2 receptor antagonist (basiliximab versus daclizumab). Four trials reported on adverse events. However, no differences between trial groups were noted. Limited data were available for meta-analysis on drug-specific adverse events such as haematological adverse events for antithymocyte globulin. No data were available on quality of life.

AUTHORS' CONCLUSIONS

Because of the low quality of the evidence, the effects of T-cell antibody induction remain uncertain. T-cell specific antibody induction seems to reduce diabetes mellitus and may reduce cytomegalovirus infection when compared with corticosteroid induction. No other clear benefits or harms were associated with the use of T-cell specific antibody induction compared with corticosteroid induction. For some analyses, the number of trials investigating the use of T-cell specific antibody induction after liver transplantation is small, and the numbers of participants and outcomes in these randomised trials are limited. Furthermore, the included trials are heterogeneous in nature and have applied different types of T-cell specific antibody induction therapy. All trials were at high risk of bias. Hence, additional randomised clinical trials are needed to assess the benefits and harms of T-cell specific antibody induction compared with corticosteroid induction for liver transplant recipients. Such trials ought to be conducted with low risks of systematic error and of random error.

Evolving frequency and outcomes of liver transplantation based on etiology of liver disease

BACKGROUND

In the background of availability of better treatments for specific liver diseases and listing of nonalcoholic steatohepatitis (NASH) as an etiology for liver transplantation (LT), data are unclear on the impact of disease etiology on the frequency of LT and liver posttransplantation outcomes.

METHODS

The United Network for Organ Sharing database (1994-2009) was queried for adults receiving first LT for primary biliary cirrhosis (PBC; n=3052), primary sclerosing cholangitis (PSC; n=3854), hepatitis C virus (HCV; n=15,147), alcoholic cirrhosis (AC; n=8940), HCV+alcohol (n=6066), NASH (n=1368), cryptogenic cirrhosis (CC; n=5856), hepatitis B virus (HBV; n=1816), and hepatocellular carcinoma (HCC; n=8588). Graft and patient survival were compared and Cox models were built to determine independent prediction of outcomes by disease etiology.

RESULTS

The frequency of LT increased for NASH, HCC, and HCV+alcohol, remained stable for AC, and decreased for PBC, PSC, HCV, CC, and HBV. The proportion of simultaneous liver-kidney transplants increased from approximately 3% in 2001 to 10% in 2009. Compared with PBC, 5-year graft and patient survival were (a) similar for PSC, NASH, and HBV (80-85%), (b) poorer for AC and CC (hazard ratio, 1-1.5), and (c) worst for HCV, HCV+alcohol, and HCC (hazard ratio, 1.5-2.4). Five-year outcomes for HCV-associated HCC were poorer compared with HCC due to other etiologies.

CONCLUSIONS

LT performed for NASH and HCC are increasing. Potent treatment options resulted in a decrease in number of transplants for HBV, HCV, and PBC. Better treatment modalities for HCV are expected to further reduce the number of LT for HCV. Excellent posttransplantation outcomes for NASH and AC are encouraging, resulting in wider acceptance of transplants for these etiologies.

Diffusion-weighted MRI of the transplanted liver

AIM

To assess the value of diffusion-weighted imaging (DWI) in evaluating parenchymal disorders following orthotopic liver transplantation (OLT).

MATERIALS AND METHODS

This institutional review board-approved, retrospective study measured the hepatic apparent diffusion coefficients (ADC) in patients following OLT. Those with vascular complications or within 3 months of OLT were excluded. A single-shot echoplanar sequence with b values of 50, 400 (or 500), and 800 s/mm(2) was performed. Liver biopsy specimens [performed with a median of 17 days after magnetic resonance imaging (MRI)] were recorded for the presence and severity of parenchymal disorders, such as acute cellular rejection, and recurrence of fibrosis in all patients, and the recurrence of viral hepatitis in patients with hepatitis C. ADC values were measured blinded to histology in 41 patients (33 males) who had 56 MRI scans.

RESULTS

There was a significant difference in ADC values associated with a histological abnormality seen on core biopsy [n=43, mean (SD) ADC of 0.91 (0.15)×10(-3) mm(2)/s] and those associated with no histological abnormality [n=13, mean (SD) ADC of 1.11 (0.17)×10(-3) mm(2)/s; (p=0.003)]. ADC values did not predict any of the individual parenchymal disorders on logistic regression analysis. When the ADC value was <0.99×10(-3) mm(2)/s, there was a sensitivity and specificity of 85% and 72%, respectively, in predicting a parenchymal disorder (area under ROC curve=0.84; 95% CI 0.72 to 0.92).

CONCLUSION

ADC measurements may help in deciding which patients require core liver biopsy after OLT. However, ADC values are not likely to be reliable in differentiating between the various parenchymal disorders.

Resveratrol and liver disease: from bench to bedside and community

Liver diseases incorporate several maladies, which can range from benign histological changes to serious life-threatening conditions. These may include inborn metabolic disease, primary and metastatic cancers, alcoholic cirrhosis, viral hepatitis and drug-induced hepatotoxicity. Liver disease remains a major cause of morbidity and mortality with significant economic and social costs. Several novel approaches are currently being studied which may provide a better therapeutic outcome. The use of naturally occurring phytochemicals, some of them obtained from dietary sources, in the amelioration of illness have recently gained considerable popularity. These agents, having anti-oxidant and anti-inflammatory properties, provide a safe and effective means of ameliorating chronic disease. Resveratrol, a grape polyphenol, has shown considerable promise as a therapeutic agent in the treatment of the aforementioned liver ailments. Several studies have highlighted the hepatoprotective properties of resveratrol. Resveratrol has been shown to prevent hepatic damage because of free radicals and inflammatory cytokines, induce anti-oxidant enzymes and elevate glutathione content. Resveratrol has also been shown to modulate varied signal transduction pathways implicated in liver diseases. This review critically examines the current preclinical in vitro and in vivo studies on the preventive and therapeutic effects of resveratrol in liver diseases. The review highlights the pharmacological mechanisms involved in mediating the aforementioned effects. Toxicity, pharmacokinetics and clinical bioavailability of resveratrol are also reviewed in this article. The challenges involved, future directions and novel approaches such as site-specific drug delivery in the use of resveratrol for the prevention and treatment of liver disease are also discussed.

Interest of BIS monitoring to guide propofol infusion during the anhepatic phase of orthotopic liver transplantation

OBJECTIVE

The anhepatic phase of orthotopic liver transplantation (OLT) is associated with significant changes in pharmacokinetics. The aim of this study was to compare the influence of this phase on propofol target concentrations during BIS guided target controlled infusion (TCI).

STUDY DESIGN

Prospective study.

PATIENTS AND METHODS

Eight patients aged 25 to 65 years, Child-Pugh status A-B scheduled for OLT were prospectively included. Anesthesia was performed using TCI of propofol (Diprifusor, Marsh pharmacokinetic model), sufentanil and cisatracurium. Propofol target concentration was adjusted to maintain BIS values between 40 and 50.

RESULTS

To maintain stable BIS values, propofol target concentrations should be decreased during the anhepatic phase versus the dissection one (2.0 microg/ml+/-0.8 versus 3.0 microg/ml+/-0.9, p<0.0001).

CONCLUSION

BIS could be useful to titrate propofol infusion during the anhepatic phase of OLT.

Role of reactive metabolites of oxygen and nitrogen in partial liver transplantation: lessons learned from reduced-size liver ischaemia and reperfusion injury

1. Hepatic resection with concomitant periods of ischaemia and reperfusion (I/R) is required to perform reduced-size liver (RSL) transplantation procedures, such as living donor or split liver transplantation. Although a great deal of progress has been made using these types of surgical procedures, a significant number of patients develop tissue injury from these procedures, ultimately resulting in graft failure. 2. Because of this, there is a real need to understand the different mechanisms responsible for the tissue injury induced by I/R of RSL transplantation (RSL + I/R), with the ultimate goal to develop new and improved therapeutic agents that may limit the tissue damage incurred during RSL transplantation. 3. The present paper reviews the recent studies that have been performed examining the role of reactive metabolites of oxygen and nitrogen in a mouse model of RSL + I/R. In addition, we present data demonstrating how the pathophysiological mechanisms identified in this model compare with those observed in a model of RSL transplantation in rats.

Gene transduction of an active mutant of akt exerts cytoprotection and reduces graft injury after liver transplantation

Akt is expected to be an effective target for the treatment of ischemia-reperfusion injury (I/R) due to its anti-apoptotic properties and its ability to activate the endothelial nitric oxide synthase (eNOS) enzyme. Therefore, this study was aimed to determine the efficacy of an active mutant of Akt (myr-Akt) to decrease I/R injury in a model of orthotopic liver transplantation in pigs. In addition, we analyzed the contribution of nitric oxide in the Akt-mediated effects by using an eNOS mutant (S1179DeNOS) that mimics the phosphorylation promoted by Akt in the eNOS sequence. Donors were treated with adenoviruses codifying for myr-Akt, S1179DeNOS or beta-galactosidase 24 h before liver harvesting. Then, liver grafts were orthotopically transplanted into their corresponding recipients. Levels of transaminases and lactate dehydrogenase (LDH) increased in all recipients after 24 h of transplant. However, transaminases and LDH levels were significantly lower in the myr-Akt group compared with vehicle. The percentage of apoptotic cells and the amount of activated-caspase 3 protein were also markedly reduced in myr-Akt-treated grafts after 4 days of liver transplant compared with vehicle and S1179DeNOS groups. In conclusion, myr-Akt gene therapy effectively exerts cytoprotection against hepatic I/R injury regardless of the Akt-dependent eNOS activation.

Histologic, viral, and molecular correlates of dengue fever infection of the liver using highly sensitive immunohistochemistry

The mechanism by which the virus associated with dengue fever can cause a fatal hepatitis is not well understood. The purpose of this study was to examine 9 cases of fatal dengue hemorrhagic fever-associated hepatitis, and to correlate the histologic findings with viral detection and cytokine response. The histologic changes were nonspecific and included massive hepatic necrosis and a pauci-cellular acute hepatitis. Viral cDNA detection by reverse transcriptase in situ polymerase chain reaction demonstrated that the fatal hepatitis was due to infection on average of >90% of hepatocytes and many Kupffer cells. Similar results were obtained using immunohistochemistry for viral protein using an automated highly sensitive system. Immunohistochemical analysis for tumor necrosis factor alpha, and interleukin-2, showed rare positive Kupffer cells. In comparison, fatal cases of hepatitis C associated liver failure demonstrated far fewer infected hepatocytes and a concomitant strong up-regulation of many cytokines, notably tumor necrosis factor alpha and interleukin-2. It is concluded that fatal dengue hemorrhagic fever is associated with acute, severe liver damage due primarily to massive direct infection of hepatocytes and Kupffer cells with minimal cytokine response. The infection can be readily detected in a few hours using an automated system that has a sensitivity equivalent to reverse transcriptase in situ polymerase chain reaction.

Safety, tolerability, and efficacy of everolimus in de novo liver transplant recipients: 12- and 36-month results

Everolimus is a macrolide immunosuppressive agent with known consistent absorption. In this double-blind study, we examined the safety and tolerability of everolimus vs. placebo in de novo liver transplant recipients. One hundred and nineteen liver allograft recipients were randomized to 1 of 4 groups: everolimus 0.5 mg bid, everolimus 1.0 mg bid, everolimus 2 mg bid, or placebo. Patients received oral cyclosporine to achieve a target trough level of 150-400 ng/mL in combination with prednisone. Primary and secondary endpoints of safety, tolerability, and efficacy were determined at 12 months, and patients were followed through 36 months. There was a trend toward fewer treated acute rejections in the everolimus group than in the placebo group: everolimus 0.5 mg: 39.3%; everolimus 1.0 mg: 30.0%; everolimus 2 mg: 29.0%; placebo: 40.0% (P = not significant). Adverse events were higher in everolimus-treated patients especially at the 4-mg/day dose, but there was no difference in the incidence of thrombocytopenia or leukopenia between all groups and renal function as determined by serum creatinine, and creatinine clearance remained stable to 36 months in everolimus-treated patients. Mean cholesterol and triglycerides increased from baseline in all treatment groups, and maximum levels were seen at 6 months. In conclusion, this study demonstrates that everolimus in combination with oral cyclosporine had an acceptable safety and tolerability profile, paving the way for additional studies in this transplant indication.

Syncytial giant cell hepatitis in human immunodeficiency virus-infected patients with chronic hepatitis C: 2 cases and review of the literature

Syncytial giant cell hepatitis (SGCH) among adult human immunodeficiency virus (HIV)-infected patients has been rarely described. Most cases have been reported in subjects coinfected with the hepatitis C virus (HCV), but its prevalence and outcome remain unknown. We performed a retrospective analysis of all cases of SGCH among 332 liver biopsies from HIV-infected patients seen at a tertiary center in Madrid, Spain, between 1984 and March 2004. Two hundred fifty specimens were obtained from HCV-coinfected patients. There were 2 cases of SGCH, leading to an observed overall prevalence of 0.6% (0.8% when considering only HCV-coinfected patients). In addition to histological changes secondary to chronic hepatitis C, the liver cords were replaced by syncytial giant cells with up to 30 nuclei. There was no histological evidence of measles (among paramyxoviruses) or herpes viruses group infections. In patient 1, there was a progressive clinical worsening after a 3-month course of prednisone, leading to liver failure and death. His postmortem liver biopsy showed more abundant giant hepatocytes accompanied with the development of a histologic pattern of severe fibrosing cholestatic hepatitis. The second patient received a prolonged course of pegylated interferon-alpha-2b and ribavirin with clearance of syncytial giant hepatocytes despite HCV-RNA persistence. SGCH is a rare histological finding among HIV-infected patients with chronic hepatitis C. Specific treatment with pegylated interferon and ribavirin can lead to histological resolution and biochemical improvement, even in the absence of HCV-RNA clearance.

Tissue assembly guided via substrate biophysics: applications to hepatocellular engineering

The biophysical nature of the cellular microenvironment, in combination with its biochemical properties, can critically modulate the outcome of three-dimensional (3-D) multicellular morphogenesis. This phenomenon is particularly relevant for the design of materials suitable for supporting hepatocellular cultures, where cellular morphology is known to be intimately linked to the functional output of the cells. This review summarizes recent work describing biophysical regulation of hepatocellular morphogenesis and function and focuses on the manner by which biochemical cues can concomitantly augment this responsiveness. In particular, two distinct design parameters of the substrate biophysics are examined--microtopography and mechanical compliance. Substrate microtopography, introduced in the form of increasing pore size on collagen sponges and poly(glycolic acid) (PGLA) foams, was demonstrated to restrict the evolution of cellular morphogenesis to two dimensions (subcellular and cellular void sizes) or induce 3-D cellular assembly (supercellular void size). These patterns of morphogenesis were additionally governed by the biochemical nature of the substrate and were highly correlated to resultant levels of cell function. Substrate mechanical compliance, introduced via increased chemical crosslinking of the basement membrane, Matrigel, and polyacrylamide gel substrates, also was shown to be able to induce active two-dimensional (2-D, rigid substrates) or 3-D (malleable substrates) cellular reorganization. The extent of morphogenesis and the ensuing levels of cell function were highly dependent on the biochemical nature of the cellular microenvironment, including the presence of increasing extracellular matrix (ECM) ligand and growth-factor concentrations. Collectively, these studies highlight not only the ability of substrate biophysics to control hepatocellular morphogenesis but also the ability of biochemical cues to further enhance these effects. In particular, results of these studies reveal novel means by which hepatocellular morphogenesis and assembly can be rationally manipulated leading to the strategic control of the expression of liver-specific functions for hepatic tissue-engineering applications.

Divergent roles of superoxide and nitric oxide in reduced-size liver ischemia and reperfusion injury: Implications for partial liver transplantation

Hepatic resection with concomitant periods of ischemia and reperfusion (I/R) are required to perform partial liver transplantation procedures such as split liver or living donor transplantation. Although great progress has been made using these types of surgeries, there remains substantial risk to both donors and recipients, with a significant number of patients developing liver injury and failure during the course these operations. Therefore, there is need to investigate the different mechanisms responsible for the tissue injury induced by ischemia and reperfusion of a reduced-size liver (RSL+I/R) with the ultimate objective of developing new therapeutic agents that may limit hepatocellular damage induced during partial liver transplantation. This review summarizes recent studies that have been performed in a mouse model of RSL+I/R. In addition, we present data demonstrating how the pathophysiological mechanisms identified in this model compare to those observed in a rat model of RSL transplantation.

Living donor liver transplantation for hepatitis C-related cirrhosis: no difference in histological recurrence when compared to deceased donor liver transplantation recipients

The question of possible earlier and more aggressive recurrence of hepatitis C virus (HCV) infection after living donor liver transplantation (LDLT) compared to deceased donor liver transplantation (DDLT) remains unanswered. To address this issue we retrospectively reviewed virological, histological, and clinical data in 67 patients (52 DDLT and 15 LDLT) who underwent liver transplant for their HCV-related cirrhosis since April 2001. Our data indicate that there is no statistical difference between LDLT and DDLT groups in mean age, Child-Turcotte-Pugh score, model for end-stage liver disease score, and gender distribution. The mean follow-up was 749 +/- 371 days in LDLT and 692 +/- 347 days in DDLT. The predominant genotype in the LDLT and DDLT are genotype 1 (LDLT, 91%; DDLT, 70%). All patients with histologically confirmed recurrent HCV had detectable HCV-RNA in serum. The histological recurrence rate of hepatitis C was 58% at 4 months, 90% at 1 year, and 100% at 2 years in LDLT patients vs. 71% at 4 months, 94% at 1 year, and 95% at 2 years in DDLT patients (not significant) Comparison of the activity of inflammation and fibrosis score at all time points failed to show a statistical difference. Kaplan-Meier survival analysis showed similar patient and graft survival rates between the 2 groups. Our data indicate that histological recurrence of HCV is an early event and virtually universal 2 years' posttransplantation, regardless of modality of donor procurement.

Clinical Outcomes of Living Donor Liver Transplantation for Hepatitis C Virus (HCV)-Positive Patients

BACKGROUND

Whether hepatitis C virus recurrence occurs earlier and with greater severity for living donor liver transplantation (LDLT) than for deceased donor liver transplantation (DDLT) has recently become a subject of debate.

METHODS

We retrospectively evaluated clinical outcomes for a cohort of 91 HCV-positive patients who underwent LDLT at Kyoto University with a median follow-up period of 25 months.

RESULTS

Overall 5-year patient survival for HCV patients was similar to that for non-HCV patients (n=209) who underwent right-lobe LDLT at our institute (69% vs. 71%). Survival rate of patients without HCC (n=34) tended to be better than that of patients with HCC (n=57) (82% vs. 60%, P=0.069). According to annual liver biopsy, rate of fibrosis progression to stage 2 or more (representing significant fibrosis) was 39% at 2 years after LDLT. Univariate analysis showed that female recipient and male donor represented significant risk factors for significant fibrosis. Progression to severe recurrence (defined as the presence of liver cirrhosis (F4) in a liver biopsy and/or the development of clinical decompensation) was observed in five patients.

CONCLUSIONS

Postoperative patient survival was similar for HCV-positive and -negative recipients in our adult LDLT series. Rates of progression to severe disease due to HCV recurrence seemed comparable between our LDLT recipients and DDLT recipients described in the literature. Although longer-term follow-up is required, our results suggest that LDLT can produce acceptable outcomes also for patients suffering from HCV-related cirrhosis.

HCV clearance and treatment outcome in genotype 1 HCV-monoinfected, HIV-coinfected and liver transplanted patients on peg-IFN-alpha-2b/ribavirin

BACKGROUND/AIMS

Differences in HCV-RNA clearance during therapy might explain the lower efficacy of peg-IFN/RBV in HIV/HCV-coinfection. There are limited data on HCV-RNA clearance and treatment outcomes in liver transplanted (LT) patients.

METHODS

To assess the rates of SVR and baseline predictors of failure after 48 weeks of weight-adjusted peg-IFN-alpha-2b/RBV in 120 patients with HCV genotype 1: 61 HCV-monoinfected, 40 HIV-coinfected and 19 LT-patients. Viral clearance was evaluated in patients completing 24 weeks of therapy (n=112, 93%).

RESULTS

SVR was significantly lower in HIV-coinfection than in HCV-monoinfection or LT (18 vs. 39 vs. 42%, P<0.02). By multivariate analysis, HIV-coinfection (OR 3.048, 95% CI 1.133-8.196; P=0.027), baseline HCV-RNA over 800,000 IU/ml (OR 2.800; 95% CI 1.121-6.993, P=0.027) and higher AST values (OR 1.009; 95% CI 1.001-1.018; P=0.028) were significantly associated to failure. Despite similar baseline HCV load (5.67 vs. 5.75 vs. 5.90 log10 IU/ml), HIV-coinfection showed significantly lower HCV-RNA decreases than HCV-monoinfection at weeks 4 (P=0.015), 12 (P=0.015) and 24 (P=0.0003), and than LT at weeks 12 (P=0.003) and 24 (P=0.023). 36/60 subjects (60%) reaching EVR by week 12 obtained SVR vs. 3/60 (5%) who did not.

CONCLUSIONS

HIV-coinfection was independently associated to treatment failure, and led to a significantly slower HCV-RNA clearance.

Spectrum of pneumonia in the current era of liver transplantation and its effect on survival

OBJECTIVE

To examine the frequency and microbial pattern of pneumonia and its effect on survival in the current era of orthotopic liver transplantation (OLT).

PATIENTS AND METHODS

At the Mayo Clinic in Jacksonville, Fla, the medical records of consecutive patients who underwent their first OLT between February 1998 and January 2001 were retrospectively reviewed through the end of the first year posttransplantation.

RESULTS

Of 401 study patients, 20 developed pneumonia; estimates of incidence with corresponding 95% confidence interval (CI) at 1 and 12 months were 3% (1%-5%) and 5% (3%-7%), respectively. Pseudomonas aeruginosa was the predominant microorganism identified (in 8 of 14 patients) during the first month after transplantation. Between the second and sixth months, 2 of the 4 cases of pneumonia were due to fungal infections of Aspergillus fumigatus. Cytomegalovirus was associated with Aspergillus in 1 patient. No other viral or Pneumocystis carnil pneumonia was diagnosed. There were only 2 cases of pneumonia between 7 months and 1 year after transplantation, neither of which was fungal. Approximately 40% (95% CI, 14%-58%) of patients with pneumonia died within 1 month after diagnosis. The relative risk of mortality in the first month after onset of pneumonia was estimated to be 24 (95% CI, 10-54), which is strong evidence of increased risk of mortality with pneumonia (P<0.001).

CONCLUSIONS

Pneumonia appears to occur less often after OLT than previously reported but still has a substantial negative effect on survival. In the early period after OLT, P. aeruginosa continues to be the predominant organism causing pneumonia.

Ocular complications after organ and bone marrow transplantation in children

BACKGROUND

Organ and bone marrow transplantation commonly are performed in children. Ocular complications usually are described as secondary to post-transplantation medications. The complication rate is unknown.

METHODS

A retrospective chart review was performed of 93 children who were younger than 18 years of age and had transplantation surgery from 1989 to 2004. The rate and type of ocular complications, including those requiring ocular surgery, were analyzed. Medications and visual loss associated with adverse effects also were studied.

RESULTS

Of the 93 patients, 74 patients met the entry criteria. Sixty-one patients had at least 1 year of follow-up, and the longest follow-up duration was 14 years. The 1-year post-transplantation complication rate was 16.0% (95% confidence interval 6.8-24.4%). Adverse effects included cytomegalovirus (CMV) retinitis, cataract, graft-versus-host disease, lymphoproliferative disorder, persistent strabismus, and transient visual loss. Four patients underwent eye surgery, including lensectomy for cataract, tarsorrhaphy for corneal ulcer, and iris biopsy. They had surgery 0.9 to 4.7 years after transplantation. Most patients were taking prednisone and cyclosporine when their complication was diagnosed. One patient's visual acuity deteriorated to no light perception in one eye and 20/250 in the other eye secondary to CMV retinitis. Most patients had a final visual acuity > or =20/40.

CONCLUSION

Transplantation surgery in children produces a significant risk of ocular impairment. The 1-year complication rate was 16.0%. Eye surgery may be required within the first few years after transplantation. Although most patients maintained a final visual acuity of 20/40 or better, one patient became bilaterally legally blind.

Mil trasplantes hepáticos en el Hospital Clínic i Provincial de Barcelona

The aim of this study was to evaluate a consecutive series of 1000 liver transplants performed in our institution and to evaluate changes over time in donors and recipients, as well as results.

MATERIAL AND METHOD

To clearly evaluate the differences between the initial transplantation period and the present period, the first 100 consecutive liver transplantations performed (June 1988-June 1990) and the last 200 consecutive liver transplantations performed (January 2001-June 2003) were compared.

RESULTS

Donor age increased (23+/-10 vs. 45+/-19), the etiology of brain death changed (severe head injury: 78% vs. 23.5%; stroke: 17% vs. 52.5%) and the percentage of donors from alternative methods to cadaveric donors increased (living donors: 12.5%) in the second period. Regarding recipients, the piggy-back technique and biliary anastomosis without T-tube were introduced in the second period. Actuarial 1-year survival was higher in the second period than in the first (84% vs. 91.3%). The need for retrasplantation in the entire series was 9.5%, with actuarial survival at 1, 5 and 10 years of 67.7%, 51.3% and 39.4%, respectively.

CONCLUSION

Because of the lack of donors and the greater number of patients on the waiting list, poorer quality donors and more critical recipients have been accepted and alternative and innovative programs have been started. Nevertheless, due to improvement in patient management before, during and after transplantation, the previous good results have been maintained.

Predictors of death on the waiting list for liver transplantation characterized by a long waiting time

The number of patients dying while on the liver transplantation (LT) waiting list (WL) has continued to increase in recent years as a result of severe shortage of organs. Therefore, it is important to evaluate the existing models that predict death on the WL and to determine the independent predictors of death. The study cohort comprised 152 adult patients listed for LT in our centre over a period of 2 years (January 2001 to January 2003). The 12-month survival rate has been calculated by Kaplan-Meier method. The survival analysis performed by Cox proportional hazard model has evaluated the three parameters which compose the model for end-stage liver disease (MELD) score. Forty-four patients (28.9%) died while listed for LT. The survival rate was 92% at 3 months, 80% at 6 months and 69% at 12 months. Median survival was not reached. MELD score was found to be an excellent predictor of death at 12 months on our WL--c-statistic (area under curve) 0.84. In our survival analysis, only international normalized (prothrombin) ratio (INR) and serum creatinine were identified as an independent predictors of death (P < 0.0001). A new simplified version of the MELD score, which does not include serum bilirubin, is proposed and its c-statistic as predictor for death on the WL at 12 months is 0.86, as good as the original MELD score, when evaluated on our list. There is a fourfold increase in mortality on our WL for LT between 3 and 12 months after the inclusion. A simplified version of the MELD score, using only serum creatinine and INR might be taken into account when predicting 12 months mortality on WL with longer waiting time, but it has to be confirmed by other prospective studies.

Pharmacokinetics of tacrolimus and mycophenolic acid are altered, but recover at different times during hepatic regeneration in rats

Hepatic regeneration is very critical to the success of living donor liver transplantation, which allows a reduced size liver to grow in size to accommodate the requirements of both the donor and the recipient. The objectives of this study were to evaluate 1) the hepatic metabolism of the two immunosuppressive drugs, tacrolimus and mycophenolic acid (MPA), and 2) the pharmacokinetics of tacrolimus and mycophenolic acid at various time points after initiation of hepatic regeneration by partial hepatectomy in rats. The hepatic intrinsic clearance of tacrolimus was decreased to 70% and 51% of the control level at the 24th h and the 6th day, respectively, but returned to normal level by day 14. The total body clearance of tacrolimus was reduced transiently but recovered completely by day 18. The hepatic intrinsic clearance of MPA was decreased to 52% and 51% of that in control rats at the 24th h and the 6th day, respectively, but recovered to normal level by day 14. The total body clearance of MPA was reduced at the 24th h but recovered by day 6. The magnitude of reduction in the clearance of tacrolimus and MPA was much smaller than what was predicted from in vitro data. The elimination clearance of MPA glucuronide was also impaired during hepatic regeneration but recovered to normal level with time. In conclusion, the pharmacokinetics of tacrolimus and mycophenolic acid were altered during hepatic regeneration but recovered completely at different rates over time. Caution must be exercised in extrapolating in vitro data to in vivo conditions during hepatic regeneration.

Diagnosis of 6 mercaptopurine hepatotoxicity post liver transplantation utilizing metabolite assays

Azathioprine and 6-mercaptopurine (6 MP) are commonly used as immunosuppression postsolid organ transplantation. Recently, a better understanding of the metabolism of these drugs has developed. 6 Mercaptopurine is metabolized by thiopurine methyl transferase (TPMT) which is under the control of a common genetic polymorphism. Genetic testing and measurement of levels of 6 MP metabolites allow identification of patients at risk of toxicity. We report two cases of cholestatic hepatocellular injury associated with 6 MP toxicity occurring after orthotopic liver transplantation. Cholestasis developed after the introduction of 6 MP. Patients underwent extensive investigation and 6 MP toxicity was considered only after all other causes had been excluded. Thiopurine methyl transferase alleles identified on genetic testing were normal as were the 6 thioguanine levels. However, 6-methyl mercaptopurine levels were significantly elevated into the toxic range. Cholestasis resolved within a few weeks of drug withdrawal. 6 Mercaptopurine hepatotoxicity can present with a variety of clinical, biochemical and histological manifestations post OLT and should be considered as a cause of liver enzyme elevation. Monitoring of 6 MP metabolite levels in addition to TPMT allele testing is useful to prevent 6 MP toxicity and to help guide therapy.

The role of selective digestive decontamination for reducing infection in patients undergoing liver transplantation: a systematic review and meta-analysis

Selective digestive decontamination (SDD) refers to the use of antimicrobials to reduce the burden of aerobic gram-negative bacteria and/or yeast in the intestinal tract to prevent infections caused by these organisms. Liver transplant patients are highly vulnerable to bacterial infection particularly with gram-negative organisms within the first month after transplantation, and SDD has been proposed as a potential measure to prevent these infections. However, the benefit of this procedure remains controversial. We undertook a systematic review and meta-analysis to determine whether SDD is beneficial in reducing infections overall and those caused by gram-negative bacteria in patients following liver transplantation. All studies that evaluated the efficacy of SDD in liver transplant patients were included. Randomized trials that included liver transplant patients given SDD versus either placebo or no treatment or minimal treatment (e.g., oral nystatin alone), and that provided adequate data to calculate a relative risk ratio, were included in the meta-analysis. Our review shows that most studies found SDD to be effective in reducing gram-negative infection. The nonrandomized and uncontrolled trials also showed benefit with SDD in reducing overall infection; however, the effect on overall infection was limited in the 4 randomized trials, in which the pooled relative risk was 0.88 (95% CI, 0.7-1.1), indicating no statistically significant reduction in infection with the use of SDD. The summary risk ratio for the association between SDD and gram-negative infection was 0.16 (95% CI, 0.07-0.37), indicating an 84% relative risk reduction in the incidence of infection caused by gram-negative bacteria in patients receiving SDD in randomized trials. In conclusion, the available literature supports a beneficial effect of SDD on gram-negative infection following liver transplantation; however, the risk of antimicrobial resistance must be considered. Larger multicenter randomized trials in this patient population to assess the effect of SDD in reducing infection and mortality, while assessing the risk of antimicrobial resistance, are needed.

Histological changes after the use of mycophenolate mofetil in autoimmune hepatitis

Corticosteroids and azathioprine are considered standard treatment for autoimmune hepatitis. There are, however, well-known systemic side effects that may preclude continuation with these immunosuppressive therapies, and small trials of the anti-metabolite mycophenolate mofetil have been reported. We report liver biopsy findings in a follow-up biopsy of a patient who had been switched from azathioprine to mycophenolate mofetil for treatment of presumed, steroid-responsive autoimmune hepatitis. Both cytoplasmic features of adaptation and nuclear alterations were noted in hepatocytes. Possible mechanisms for these findings are discussed.

Role of NADPH oxidase-derived superoxide in reduced size liver ischemia and reperfusion injury

Hepatic resection with concomitant periods of ischemia and reperfusion (I/R) is required to perform reduced size liver transplantation such as split liver or liver donor transplantation. Although great progress has been made using these types of surgeries, there remains substantial risk to both donors and recipients, with a significant number of patients developing liver injury and failure. The objective of this study was to assess the roles of superoxide (O(2)(-)) and tumor necrosis factor-alpha (TNF-alpha) in the pathophysiology of a mouse model of reduced size liver combined with ischemia and reperfusion (RSL+I/R). We found that all male mice subjected to RSL+I/R died within 3-5 days following surgery. Mortality was always preceded by dramatic increases in liver injury and TNF-alpha expression in the absence of neutrophil infiltration. Using a long-lived, polycationic form of human manganese superoxide dismutase (pcMnSOD), NADPH oxidase-deficient mice (gp91(-/-)) or a monoclonal antibody directed against mouse TNF-alpha, we demonstrated that hepatocellular injury (and mortality) were significantly attenuated. In addition, we found that pcMnSOD administration or NADPH deficiency reduced expression of TNF-alpha. Taken together, our data suggest that NADPH oxidase-derived O(2)(-) plays an important role in the pathophysiology of RSL+I/R-induced liver injury via its ability to enhance expression of TNF-alpha. We propose that therapies directed toward scavenging of O(2)(-), inhibiting NADPH oxidase, and/or immuno-neutralizing TNF-alpha may prove useful in limiting the liver injury induced by surgical procedures that require resection and I/R such as split liver or living donor liver transplantation.

Impact of evolving trends in recipient and donor characteristics on cytomegalovirus infection in liver transplant recipients

BACKGROUND

This study determines whether the recipient and donor characteristics that influence the cytomegalovirus (CMV) infection rate after liver transplantation have changed.

METHODS

The recipient and donor characteristics that may affect the rate of CMV infection were assessed in 232 liver transplant recipients at our institution during a 14-year period (1989-2003).

RESULTS

Since 1989, the age of recipients (P=0.0001) and donors (P=0.0001) has increased significantly. Pretransplant CMV seropositivity in recipients has decreased significantly (P=0.0001, 86.4% [1989-1992] to 53.7% [2000-2003]), whereas donor CMV seropositivity has remained unchanged (P>0.20). As a result, there has been a significant increase in the proportion of high-risk (CMV recipient-/donor+) patients (P=0.012); 10.6% of recipients from 1989 to 1992 versus 24.1% of recipients from 2000 to 2003 were CMV recipient-/donor+. The Child-Pugh scores of recipients have remained unchanged over time. However, the proportion of patients undergoing transplantation while being cared for in the intensive care unit has decreased significantly over time (P=0.0002). Despite an increase in the rate of CMV infection (P=0.09), the incidence of CMV disease has decreased significantly (P=0.0004).

CONCLUSIONS

The proportion of high-risk patients (CMV recipient-/donor+) has increased significantly over time, attributable largely to a declining rate of CMV seropositivity in recipients before transplantation. These data have implications for guiding prophylactic practices and resource use after liver transplantation.