Long-term survival after liver transplantation in 4,000 consecutive patients at a single center

The Importance of Analyzing Graft and Patient Survival by Cause of Failure: An Example Using Pediatric Small Intestine Transplant Data

BACKGROUND

Although graft and patient survival are vital in reporting overall results of clinical transplant studies, these outcomes do not account for distinct types of graft failure and death, which clearly exist in pediatric small intestine transplantation (Itx). The use of a cause-specific hazard (CSH) approach may provide more precise identification and thus greater insight as to why certain factors are prognostically important.

METHODS

Among 119 pediatric patients who received primary Itx at our center since 1994, Cox model stepwise regression analyses were performed to identify prognostic factors for the following CSH rates: intestinal graft failure (IGF)/death due to rejection, death due to infection not triggered by IGF, and intestinal graft loss/death due to other causes.

RESULTS

Two factors were associated with a significantly higher rate of developing IGF due to rejection (23 such failures): receiving an isolated intestine or liver-intestine transplant (P=0.00001) and receiving no induction agent (P=0.006). Conversely, age at transplant <1 year was the single factor associated with a significantly higher death rate due to infection (P=0.0005) (21 such deaths). Two characteristics were associated with a significantly higher death rate due to other causes: being in the hospital pretransplant (P=0.007) and not receiving daclizumab induction therapy (P=0.02) (24 such deaths). Although these four factors (transplant type/age/hospital status/induction therapy) were, for the most part, associated with graft/patient survival, the CSH analysis more precisely identified their prognostic value and achieved greater statistical power.

CONCLUSIONS

A CSH approach should be used in conjunction with overall outcome analyses.

The first one thousand liver transplants in Turin: a single-center experience in Italy

The first Italian liver transplant center to reach the goal of 1000 procedures was Turin. The paper reports this single-center experience, highlighting the main changes that have occurred over time. From 1990 to 2002, 1000 consecutive liver transplants were performed in 910 patients, mainly cirrhotics. Surgical technique was based on the preservation of the retrohepatic vena cava of the recipient. The veno-venous bypass was used in 30 cases only and abandoned since 1997. Operating time, warm ischemia time and length of hospital stay significantly decreased over the years, while operating room extubation became routine. Immunosuppression pivoted on cyclosporine A. Management of retransplantations, marginal grafts, and of HCV-positive, HBV-positive and hepatocellular carcinoma recipients were optimized. Median follow-up of the patients was 41 months. Overall survival rates at 1, 5 and 10 years were 87%, 78% and 72% respectively. Survival rates obtained in the second half of the cases (1999-2002 period) were significantly better than those obtained in the first half (1990-1998 period) (90% vs. 83% at 1 year and 81% vs. 76% at 5 years respectively). Increasing experience in liver transplant surgery and postoperative care allowed standardization of the procedure and expansion of the activity, with parallel improvement of the results.

Sirolimus conversion after liver transplantation: improvement in measured glomerular filtration rate after 2 years

METHODS

We reviewed our prospectively maintained database of 2005 liver transplantations. Therapy was either started de novo or converted from calcineurin inhibitors (CNIs) to sirolimus as the main immunosuppressive agent for nephrotoxicity or rejection. Glomerular filtration rate (GFR) was determined with iodine 125-labeled sodium isthalamate (Glofil-125), and serum creatinine concentration was obtained before and 3 months after transplantation, and yearly in both groups. Sirolimus levels were 10 to 15 ng/mL in patients at less than 3 months after transplantations and 5 to 10 ng/mL in the remaining patients. All patients received mycophenolate mofetil as maintenance therapy.

RESULTS

Data for 29 patients in the de novo group and 35 in the conversion group were reviewed. Patients in the de novo group demonstrated an acute cellular rejection rate of 17.2%, 40% of which were steroid resistant. In this group, 48.2% discontinuation of sirolimus was necessary because of adverse effects. Patients in the conversion group demonstrated an acute cellular rejection rate of 2.8% and a 34.3% rate of sirolimus discontinuation. Seventeen (56.7%) patients at 1 year and 8 (44.4%) patients at 2 years demonstrated continued improvement in GFR. In the conversion group, case-control analysis did not demonstrate a significant difference in GFR and serum creatinine concentration (P > .05) at 1 and 2 years after conversion. At the time of review, no patients in the conversion group required hemodialysis.

CONCLUSIONS

Conversion to sirolimus therapy is an effective strategy in improving renal function in patients with CNI-induced nephrotoxicity and can be done without increased rejection. Most of our patients (65.7%) tolerated sirolimus conversion. Of these, 56.7% and 44.4% demonstrated continued increase in GFR with the CNI-free regimen at 1 and 2 years, respectively. Long-term, large-population, prospective, randomized, controlled studies should further validate these results.

Relationships of tacrolimus pharmacokinetic measures and adverse outcomes in stable adult liver transplant recipients

BACKGROUND AND OBJECTIVES

Alternative measures to trough concentrations [non-trough concentrations and limited area under the concentration-time curve (AUC)] have been shown to better predict tacrolimus AUC. The aim of this study was to determine if these are also better predictors of adverse outcomes in long term liver transplant recipients.

METHODS

The associations between tacrolimus trough concentrations (C(0)), non-trough concentrations (C(1), C(2), C(4), C(6/8)), and AUC(0-12) and the occurrence of hypertension, hyperkalaemia, hyperglycaemia and nephrotoxicity were assessed in 34 clinically stable liver transplant patients.

RESULTS AND DISCUSSION

The most common adverse outcome was hypertension, prevalence of 36%. Hyperkalaemia and hyperglycaemia had a prevalence of 21% and 13%, respectively. A sequential population pharmacokinetic/pharmacodynamic approach was implemented. No significant association between predicted C(0), C(1), C(2), C(4), C(6/8) or AUC(0-12) and adverse effects could be found. Tacrolimus concentrations and AUC measures were in the same range in patients with and without adverse effects.

CONCLUSIONS

Measures reported to provide benefit, preventing graft rejection and minimizing acute adverse effects in the early post-transplant period, were not able to predict adverse effects in stable adult liver recipients whose trough concentrations were maintained in the notional target range.

Thrombotic and nonthrombotic hepatic artery complications in adults and children following primary liver transplantation with long-term follow-up in 1000 consecutive patients*

Arterial complications have a major impact on survival after liver transplantation (LTx). The aim of this study was to examine arterial complications in adults and children after LTx. A total of 1000 consecutive primary LTx patients [mean age 40.5 years: 600 males, 400 females, 834 adults; 166 children (age <18 years)] were studied. Forty-two patients (4.2%; 31 adults, 11 children) developed hepatic artery thrombosis (HAT). Thrombosis in children occurred significantly early (mean 5.4 days) compared with adults (mean 418.7 days, P = 0.0001). Nonthrombotic complications occurred in 30 patients (29 adults, one child). Overall, 13-year patient survival after HAT was 43.2% (72.7% children, 32.9% adults). For nonthrombotic complications, 54.3% of adults died and 69.4% grafts were lost. An overall incidence of 4.2% thrombotic and 3.2% nonthrombotic complications was observed. Rate of HAT was higher in children, but survival was better compared with adults.

Long-Term Survival and Causes of Late Graft Loss After Adult-to-Adult Living Donor Liver Transplantation

The vast amount of experience with deceased donor liver transplantation allows for the evaluation of the causes underlying late graft loss and the adoption of strategies for its prevention. In contrast, the long-term results or causes of late graft loss after adult-to-adult living donor liver transplantation have not been fully examined. Thus, we analyzed 176 adult recipients who survived at least 1 year after living donor liver transplantation. The median follow-up period was 33 months. Of the 176 recipients, eight died and three others underwent retransplantation. The most common cause of graft loss in our series was cholangitis (n = 4), which might be due partly to technical problems. The 3-year and 5-year patient survival rates of the subjects were 95% and 90%, respectively. Long-term survival after living donor liver transplantation was satisfactory in our series. Further improvement of surgical techniques for biliary reconstruction may reduce late graft loss.

Immunosuppression for liver transplantation in HCV-infected patients: mechanism-based principles

We retrospectively analyzed 42 hepatitis C virus (HCV)-infected patients who underwent cadaveric liver transplantation under two strategies of immunosuppression: (1) daily tacrolimus (TAC) throughout and an initial cycle of high-dose prednisone (PRED) with subsequent gradual steroid weaning, or (2) intraoperative antithymocyte globulin (ATG) and daily TAC that was later space weaned. After 36 +/- 4 months, patient and graft survival in the first group was 18/19 (94.7%) with no examples of clinically serious HCV recurrence. In the second group, the three-year patient survival was 12/23 (52%), and graft survival was 9/23 (39%); accelerated recurrent hepatitis was the principal cause of the poor results. The data were interpreted in the context of a recently proposed immunologic paradigm that is equally applicable to transplantation and viral immunity. In the framework of this paradigm, the disparate hepatitis outcomes reflected different equilibria reached under the two immunosuppression regimens between the relative kinetics of viral distribution (systemically and in the liver) and the slowly recovering HCV-specific T-cell response. As a corollary, the aims of treatment of the HCV-infected liver recipients should be to predict, monitor, and equilibrate beneficial balances between virus distribution and the absence of an immunopathologic antiviral T-cell response. In this view, favorable equilibria were accomplished in the nonweaned group of patients but not in the weaned group. In conclusion, since the anti-HCV response is unleashed when immunosuppression is weaned, treatment protocols that minimize disease recurrence in HCV-infected allograft recipients must balance the desire to reduce immunosuppression or induce allotolerance with the need to prevent antiviral immunopathology.

17beta-estradiol differentially activates mitogen-activated protein-kinases and improves survival following reperfusion injury of reduced-size liver in mice

Ischemia-reperfusion injury (I/R-I), which is unavoidable in liver transplantation, impairs liver regeneration and predisposes to liver failure. The three major mitogen-activated protein-kinases (MAPKs): ERK, p38, and JNK, are critical in the transmission of signals triggered by proinflammatory cytokines, by stress, and by growth factors. JNK and p38alpha activation have been associated with apoptosis; p38beta with cell survival; and ERK with proliferation. Previous studies have demonstrated gender dimorphism in hepatocellular dysfunction after experimental trauma and hemorrhage. Female mice are protected to a much greater extent from I/R-I than male mice. We assessed the effects of 17beta-estradiol (17beta-E) on liver function, host survival, and cellular activation of MAPK in a murine model of I/R-I in reduced-size livers. C57BL/6 mice were subjected to 45 minutes of warm ischemia (70% of the liver mass). After reperfusion, the nonischemic lobes were excised. Vehicle, 17beta-E or the estrogen receptor antagonist ICI-182780, was delivered 1 hour before the injury. We evaluated AST and apoptosis as well as activation of JNK, p38, and ERK. Female mice showed a lower level of hepatocellular injury (AST = 445 +/- 82 IU/L) after I/R-I compared with male mice (AST = 1400 +/- 210). 17beta-E decreased the liver injury in male mice (AST = 522 +/- 77), an effect that was partially reversed by ICI-182,780 (910 +/- 92). A higher rate of apoptosis was observed in male animals given saline (enrichment factor = 7.22 +/- 0.8) versus those treated with 17beta-E (5.85 +/- 0.3, P < .05). A significant increase in liver regeneration, as assessed by the percentage of liver weight/body weight was demonstrated in females (184% +/- 24%) and male mice given 17beta-E (168% +/- 22%) compared with male mice given vehicle (9% +/- 4%). 17beta-E significantly down-regulated JNK and p38alpha activities, whereas I/R-I promoted p38beta and ERK activation. These results suggest that the cytoprotective effects of 17beta-E on I/R-I to reduced-size livers are associated with selective modulation of MAPK kinases.

Evaluation of matrix metalloproteinases and their endogenous tissue inhibitors in biliary atresia-associated liver fibrosis

BACKGROUND/PURPOSE

Matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs) are major proteases responsible for remodeling the liver tissue, but their roles in biliary atresia (BA)--associated liver fibrosis are not clear.

METHODS

A DNA microarray containing complementary DNA clones of 10 MMPs and 4 TIMPs was used to compare the expression profiles of the liver cytokines among 3 patients with BA at the time of Kasai procedure (KP) with 3 at the time of liver transplantation (LT). Liver samples from 2 children without liver fibrosis were used as normal controls. Those genes that were differentially expressed by more than 2-fold between groups were further quantified with real time quantitative reverse transcription-polymerase chain reaction (QRT-PCR) and validated with gel electrophoresis.

RESULTS

In normal human liver, messenger RNAs (mRNAs) of TIMP-1, -2, and -3, but not of TIMP-4 and none of the 10 MMPs studied, were expressed in DNA microarray. With progression of liver fibrosis, only mRNA of MMP-7, but not other MMPs, was induced to express at a significantly higher level in the array. Despite its low level of expression, MMP-9 mRNA was significantly upregulated in KP but downregulated in LT, whereas MMP-2, which was not showed in the array, was significantly upregulated in LT than in KP and control in real time QRT-PCR. There was a more than 2-fold increase in TIMP-1 and TIMP-2 mRNA expression in LT over control in the array, which was confirmed in subsequent real time QRT-PCR. The expression of TIMP-3 mRNA was significantly downregulated in KP than in control.

CONCLUSIONS

This study verified differential expression of MMPs and TIMPs in different stages of BA, with emphasis on the role of TIMP-1, -2, and -3 as well as MMP-2, -7, and -9 transcripts in remodeling of liver tissue during the progress of BA-associated liver fibrosis.

Using root cause analysis to improve survival in a liver transplant program

BACKGROUND

With the advent of programs such as the American College of Surgeons-National Surgical Quality Improvement Program, surgical services will be compared with their peers across the United States. At times, many programs will experience lower-than-expected outcomes. During July 1, 1998, to June 30, 2000 our 1-year graft (76.86%, P = 0.23) and patient (80.61%, P = 0.016) survivals after liver transplantation were lower than our expected rates (graft 81.89% and patient 88.3%), according to the U.S. Scientific Registry of Transplant Recipients (SRTR).

METHODS

We used aggregate root cause analysis to determine underlying reasons for our patient deaths. Two of our surgeons performed a systematic review of all our center's liver transplant patient deaths from January 1, 1995, to December 31, 2000. Each phase of the transplant process was reviewed.

RESULTS

Of 355 patients receiving their first transplant, there were 90 deaths, with 188 root causes identified. The apportionment according to phase of the transplant process was patient selection, 50%; transplant procedure, 17%; donor selection, 15%; post-transplant care, 8%, and psychosocial issues, 10%. Risk reduction action plans were developed, and several important changes made in our care protocol. In April 2004, SRTR data revealed that for patients transplanted between January 1, 2001 and June 30, 2003, our 1-year liver graft survival of 90.73% (P = 0.018) was significantly higher than the national expected rate of 84.48%. Our 1-year patient survival rate of 92.66% (P = 0.285) was higher than the expected rate of 89.29%.

CONCLUSIONS

Lower-than-expected outcomes can provide an impetus for improving patient care and raising the quality of a surgical service. Aggregate root cause analysis of adverse events is a valuable method for program improvement.

Introduction of MMF in conjunction with stepwise reduction of calcineurin inhibitor in stable liver transplant patients with renal dysfunction

Mycophenolat mofetil (MMF) is a new imunosuppressant without nephrotoxic adverse effects. The aim of this study was to evaluate feasibility and effect of MMF introduction in conjunction with stepwise reduction of calcineurin inhibitors (CNI) in stable liver transplant patients with chronic CNI-induced renal dysfunction (RDF). In the MMF-group (n=27) but not in the controls (n=16), mean serum level of creatinine fell from a baseline of 227.4+/-67.9 micromol/l to 159.2+/-48.2 micromol/l (P<0,001), while mean urea level declined significantly from a baseline of 18.5+/-8.7 mmol/l to 11.4+/-4.2 mmol/l 6 months after initiation of MMF. Additionally, systolic and diastolic blood pressure values improved. In 52% of patients, dose reduction (n=11) or withdrawal (n=3) of MMF was necessary due to gastrointestinal or hematologic adverse effects. But also in patients on low dose MMF, there was a significant improvement of renal function without increased immunological risk.

Greater early pancreas graft loss in women compared with men after simultaneous pancreas-kidney transplantation

BACKGROUND

Gender differences in graft survival has been reported after some types of organ transplantation, but not after pancreas transplantation. This study compares graft survival between women and men after simultaneous pancreas-kidney transplantation (SPK).

METHODS

All first time SPK (n = 163) transplants (109 M/54 F) performed between 1989 and 2000 at University of Nebraska Medical Center, where data was available, were analyzed for overall graft and patient survival. Graft failure was then subdivided into early (<6 months), and late (>6 months), and compared between women and men.

RESULTS

The 5-yr pancreas and kidney graft survival rates for all SPK recipients was 86% [95% confidence interval (CI) = 81-92%] and 87% (95% CI = 82-93%), respectively. While overall pancreas graft survival in women was similar to men (p = 0.16), early pancreas graft failure was greater in women than men (p = 0.010) with no one cause for failure predominant. There was no gender difference in late pancreas graft failure or in early, or late kidney graft failure in the same recipients. The gender difference was unexplained by differences in age, immunosuppression, body mass index (BMI), or diabetes duration between women and men.

CONCLUSIONS

This is the first report of a gender difference in pancreas graft survival after SPK with greater early (<6 months) pancreas graft failure in women than men. With no gender difference in kidney graft failure in the same individuals, gender differences in immune responses are unlikely to be the cause. Multiple variables likely contribute.

Matrilysin (MMP-7) is a major matrix metalloproteinase upregulated in biliary atresia-associated liver fibrosis

Matrix metalloproteinases (MMPs) are the proteases responsible for tissue remodeling during liver fibrosis caused by various disorders including biliary atresia. However, information regarding the relative contribution of these proteases to liver fibrosis is still limited. We studied matrix metalloproteinase-2 (MMP-2), -7, -9 and -13 mRNA expressions in the liver tissue of early-stage biliary atresia at the time of Kasai's procedure, late-stage biliary atresia at the time of liver transplantation with advanced fibrosis and nondiseased control without liver fibrosis. The results of real-time quantitative reverse transcriptase-PCR analysis revealed that only MMP-2 and -7 expressions were significantly different between groups. MMP-2 was significantly higher in Liver Transplantation group than both in Control (P=0.010) and in Kasai's Procedure (P=0.001) groups, whereas the difference of MMP-2 expression between Control and Kasai's Procedure was not significant. However, the relative expression level of MMP-7 was sequentially elevated when comparing Control, Kasai's Procedure and Liver Transplantation groups, and there was significant (P=0.019) difference when comparing Control and Liver Transplantation groups. Moreover, the fold difference in MMP-7 mRNA was much higher than that in MMP-2 mRNA between groups. The expressions of MMP-7 were further confirmed by agarose gel electrophoresis and Western blotting. Immunohistochemical analysis revealed a significant positive correlation of the scores of MMP-7 immunostaining with the stages of liver fibrosis. In situ hybridization demonstrated that the bile ductular epithelial cells, Kupffer cells and hepatocytes were the major producers of matrix metalloproteinase-7 in the liver. Our results imply that MMP-7 is a major MMP associated with the tissue remodeling during the progression of liver fibrosis in biliary atresia.

OKT3 and ganciclovir treatments are possibly related to the presence of Epstein-Barr virus in serum after liver transplantation

The development of Epstein-Barr virus (EBV) associated lymphoproliferative disorder (PTLD) is related to EBV genome numbers in serum or plasma and B-cells, and the level of immunosuppression. EBV DNA viremia, defined as presence of EBV genomes in serum or plasma, is common in immunodeficiency. This survey of EBV viremia was performed by real-time polymerase chain reaction (PCR) on consecutive serum samples of 21 patients with acute (n = 3) or chronic liver disease (n = 18) during the first year after liver transplantation (LTX). Cytomegalovirus (CMV) DNA was analyzed with PCR in serum or leukocytes. The levels of EBV and CMV viremia were related to PTLD and the effect of different anti-rejection regimens. All patients were EBV-seropositive pre-LTX. In total, 24 of 152 (16%) samples from 10 of 21 (48%) individuals were EBV positive [five of 11 cyclosporin A (CsA); five of 10 tacrolimus treated cases]. EBV viremia was demonstrated in five of seven patients with OKT3 therapy. The number of EBV DNA positive samples was highest (26%) at 14 days after LTX. In the OKT3 treated groups, the medians of EBV DNA copy numbers were 1600/ml (range 230-7200) and 380/ml (range 120-860) in the CsA and tacrolimus patients, respectively (P < 0.02). One patient developed EBV lymphoma and another one EBV hepatitis 13 months and 24 days post-LTX, respectively. Both patients had received OKT3. Their EBV genome load was not significantly different from what was found in other patients. After ganciclovir therapy, EBV DNA was eradicated from serum in four of five patients for several months. EBV DNA load was not affected by CMV infection or disease. We conclude that presence of EBV in serum is a possible marker of an active infection and an early ganciclovir therapy may be beneficial. Quantification of EBV load offers the potential to implement pre-emptive interventions.

Analysis of long-term outcomes of 3200 liver transplantations over two decades: a single-center experience

OBJECTIVE

Few studies have evaluated long-term outcomes after orthotopic liver transplantation (OLT). This work analyzes the experience of nearly 2 decades by the same team in a single center. Outcomes of OLT and factors affecting survival were analyzed.

METHODS

Retrospective analysis of 3200 consecutive OLTs that were performed at our institution, between February 1984 and December 31, 2001.

RESULTS

Of 2662 recipients, 578 (21.7%) and 659 (24.7%) were pediatric and urgent patients, respectively. Overall 1-, 5-, 10-, and 15-year patient and graft survival estimates were 81%, 72%, 68%, 64% and 73%, 64%, 59%, 55%, respectively. Patient survival significantly improved in the second (1992-2001) versus the era I (1984-1991) of transplantation (P < 0.001). Similarly, graft survival was better in the era II of transplantation (P < 0.02). However, biliary and infectious complications increased in era II. When OLT indications were considered, best recipient survival was obtained in children with biliary atresia (82%, 79%, and 78% at 1, 5, and 10 years, respectively), while malignant disease in adult patients resulted in the worst outcomes of 68% and 43% at 1 and 5 years, post-OLT. Further, patients <18 years and nonurgent recipients exhibited superior survival when compared with recipients >18 years (P < 0.001) or urgent patients (P < 0.001). Of 13 donor and recipient variables, era of OLT, recipient age, urgent status, donor age, donor length of hospital stay, etiology of liver disease, retransplantation, warm and cold ischemia, but not graft type (whole, split, living-donor), significantly impacted patient survival.

CONCLUSIONS

Long-term benefits of OLT are greatest in pediatric and nonurgent patients. Multiple factors involving the recipient, etiology of liver disease, donor characteristics, operative variables, and surgical experience influence long-term survival outcomes. By balancing and matching these factors with a given recipient, optimum results can be achieved.

Gender differences in hepatic ischemic reperfusion injury in rats are associated with endothelial cell nitric oxide synthase-derived nitric oxide

AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated with endothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO).

METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissue malondialdehyde (MDA) content, and severity of hepatic I/R injury.

RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs 45.3±10.1 μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs 668.7±78.7 U/L, 1.71±0.18 μg/L and 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β-estradiol (E₂) (M+E₂ group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01). The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E₂ group than in M group (P<0.01 and P<0.05). The NOS inhibitor N^w-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats.

CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOS-derived NO.

Liver transplantation for severe intrahepatic noncirrhotic portal hypertension

Intrahepatic noncirrhotic portal hypertension can be idiopathic or associated with known toxic, developmental, vascular, or biliary tract diseases. Most patients are successfully managed medically or with shunting procedures. The goal of this study was to explore the reasons some patients require orthotopic liver transplantation (OLT). The clinical features, gross and microscopic liver explant pathology, and posttransplantation course in 16 patients who underwent OLT for intrahepatic noncirrhotic portal hypertension were studied. There were 11 men and 5 women with a mean age of 47 years. Clinical manifestations included gastrointestinal varices (n = 12), ascites (n = 8), encephalopathy (n = 3), and hepatopulmonary syndrome (n = 3). Cirrhosis was misdiagnosed clinically, radiographically and/or histologically in 13 patients (81%). Grossly, liver explants weighed a mean of 1,100 g, and 12 had a nodular appearance. Histologically, all 16 livers had portal tract vascular abnormalities, 15 had nodular regenerative hyperplasia (NRH), and 9 had incomplete septal cirrhosis. After OLT, mild NRH features were noted in 2 patients, and 1 of these patients developed evidence of portal hypertension. This study demonstrates that a subset of patients with intrahepatic noncirrhotic portal hypertension have severe symptoms requiring OLT. Accurate pre-OLT diagnosis is frequently difficult at advanced stages of the disease; 81% of our patients carried a diagnosis of cirrhosis. Morphologically, the explanted livers showed evidence of vascular abnormalities, NRH, and increased fibrosis, but not cirrhosis. Importantly, however, a diagnosis of cirrhosis is not required in this group of patients to qualify them for OLT, and these patients have good long-term graft function after OLT.

A novel approach to managing variation: outpatient therapeutic monitoring of calcineurin inhibitor blood levels in liver transplant recipients

OBJECTIVE

To apply the principles of statistical process control (SPC) to manage calcineurin inhibitor (CNI) blood levels. We hypothesized that the use of SPC would increase the proportion of CNI blood levels in the target range.

STUDY DESIGN

The study population consisted of 217 patients more than 3 months after liver transplantation. After demonstration of proof of concept using the rapid cycle improvement process, SPC was applied to the entire population. The change package included definition of target ranges for CNI, implementation of a web-based tool that displayed CNI blood levels on a control chart, and implementation of a protocol and a checklist for management of CNI blood levels. The principal outcome measure was the proportion of CNI blood levels in the target range.

RESULTS

In the pilot study, the proportion of CNI blood levels in the target range increased from 50% to 85%. When the protocol was spread to the entire population, the proportion of drug levels in the target range increased to 77% from 50% (P < .001), whereas the range of CNI levels decreased. The rate of allograft rejection did not change.

CONCLUSIONS

Utilization of SPC increased the proportion of CNI blood levels in target range. These observations may be applicable to the care of other chronic healthcare problems.

Sexual dimorphism in endotoxin susceptibility after partial hepatectomy in rats

BACKGROUND/AIMS

Liver failure due to endotoxemia after hepatectomy is a fatal complication. Little is known regarding the gender influence on this pathophysiological condition. This study was conducted to investigate whether a gender difference exists in the endotoxin susceptibility after hepatectomy.

METHODS

Sexually mature male and female rats received an intravenous administration of lipopolysaccharide (LPS), as endotoxin, 48h after a two-thirds hepatectomy.

RESULTS

The 24-h survival rate after LPS administration was significantly higher in females (75%) than in males (38%). Ovariectomy reduced the survival rate in females to 44%. Plasma tumor necrosis factor-alpha levels 1h after LPS were significantly elevated in males and ovariectomized females. The inducible nitric oxide synthase (iNOS) gene expression in liver and spleen, and consequent nitric oxide production 3h after LPS were significantly enhanced in males and ovariectomized females when compared to females, in addition to less functional and structural liver damage in females.

CONCLUSIONS

Our results indicate a gender difference in the susceptibility to endotoxemia in the early phase after hepatectomy. Female tolerance to these conditions may be mediated by an inhibition of excessive inflammatory response in the liver and the spleen, partially via the suppression of iNOS gene up-regulation.

An open, randomized, multicenter clinical trial of oral tacrolimus in liver allograft transplantation: a comparison of dual vs. triple drug therapy

Triple therapy combining an anticalcineurin agent, corticosteroids, and azathioprine (AZA) in liver transplantation has been frequently applied, particularly in Europe. Debates have arisen concerning the use of a third drug (AZA), mainly in patients receiving tacrolimus (TAC). An open-label, multicenter, prospective, and randomized trial was performed to assess the efficacy and safety of TAC and corticosteroids (dual therapy [D]) vs. TAC, corticosteroids, and AZA (triple therapy [T]) in liver transplantation. A total of 180 patients were randomized, 92 in D and 88 in T group. Patients were followed during 3 months for efficacy and safety and up to 24 months for patient and graft survival assessments. The rate of biopsy-proven acute rejection was higher in D than in T group (40.7% vs. 24.4%; P = 0.021). A higher incidence of positive HCV status in D group (55.6% vs. 40.7%; P = 0.049) may explain this difference, since significantly more patients of this HCV subpopulation experienced acute rejection when treated with D therapy (48% vs. 20%; P = 0.008). No treatment differences were apparent for HCV-negative patients. The 24-month graft survival tended to be inferior in T group, 69.8% vs. 75.8% (P = 0.283). Similar results were observed regarding patient survival at the same time point, with values of 72.9% vs. 76.9% (P = 0.573), favoring D group. Both regimens showed comparable safety profiles with the exception of hematological abnormalities, which were more frequently observed in T group. In conclusion, both regimens were shown to be effective although increased toxicity and a trend towards a lower graft and patient survival were observed in T group.

Invasive Pilzinfektionen bei Patienten nach Lebertransplantation. Invasive fungal infections in patients after liver transplantation

Advances in surgical technique, immunosuppression, and medical management have greatly improved clinical results after liver transplantation (LTx). Fungal infections in LTx-patients still represent serious complications and are associated with a significant decrease in survival. The majority of fungal infections in LTx-patients are caused by Candida species, which is explained by the major abdominal surgery. Aspergillus infections are second common, whereas other fungal infections such as pneumocystosis, cryptococcosis, or zygomycosis represent rare events. The high mortality of invasive fungal infections in LTx-recipients is explained by the severity of the underlying medical condition and by difficulties in diagnosis and medical therapy. Currently available diagnostic tests do not allow a timely and reliable diagnosis of invasive fungal infections in LTx-patients. Amphotericin B has been the standard treatment for invasive candidiasis and aspergillosis for many years but the high frequency of side effects limits its application. Fluconazole is widely used due to better tolerability and fewer drug interactions. Disadvantages are the lack of activity against Aspergillus species and the selection of resistant Candida strains. Progress is to be expected from new antimycotic agents belonging to azoles (voriconazole) and echinocandins (caspofungin) as these are less toxic and have a broad range of antimycotic activity. Analysis of prognostic factors allows identifying LTx-patients at high risk for invasive fungal infection. Antimycotic prophylaxis or pre-emptive therapy may improve clinical outcome in this patient subgroup.

Tacrolimus for Primary Liver Transplantation: 12 to 15 Years Actual Follow-Up With Safety Profile

BACKGROUND

Tacrolimus has been increasingly used for liver transplantation during the last decade. The drug has immunological advantages in short- to medium-term follow-up. However, data on longitudinal follow-up are lacking.

AIM

The aim of the present report was to examine the impact of tacrolimus in primary adult and pediatric liver transplantation (LTx) patients.

MATERIAL AND METHOD

One thousand consecutive primary LTx patients were performed under tacrolimus between August 1989 and December 1992 were followed up until August 2004. Mean follow-up was 13.4 +/- 0.92 (range, 11.7-15) years. There were 600 males and 400 females with a mean age of 42.6 +/- 20.2 years. There were 166 children (age 18 years or younger) and 834 adults, of whom 204 were older than 60 years (seniors).

RESULTS

Four hundred ninety-seven (49.7%) patients died in the follow-up period. The overall 15-year actuarial patient survival rate was 51.4%. The survival rate for children was significantly better (81.3%) compared with adults (47.5%) and seniors (36.4%) (P = .0001). One hundred fifty-one patients received a second LTx, 22 patients received a third LTx, and 4 patients received a fourth LTx. Over all 15 years the actuarial graft survival rate was 46.1%. At last follow-up, 69.1% of patients were off steroids. The majority of late deaths were due to age-related complications, recurrence of disease, and De novo cancers.

CONCLUSION

The data on longitudinal follow-up have shown actuarial survival for children to be significantly better than in adults and seniors. Graft loss from immunological causes are rare even with long-term follow-up.

Bildgebende Diagnostik bei Lebertransplantationen

Complimentary to orthotopic liver transplantation (OLT), living donor liver transplantation (LDLT) is increasingly considered a therapeutic option in the therapy of end-stage liver disease. Accurate pre- and postoperative imaging is crucial for the transplantation success and represents an established part of the current evaluation algorithms. This article summarizes the most important requirements and the current imaging standards. Preoperative imaging is important for exclusion of transplantation contraindications in the recipient and for reliable assessment of anatomical variants in the donor. The main purpose of postoperative imaging is the early detection and characterization of complications. In both instances, multislice CT currently represents the most versatile and reliable imaging modality, still superior to MRI. For postoperative follow-up, the imaging modality of first choice is still bedside ultrasound; however, unclear findings usually need to be further assessed by CT.

Procuring Organ Donors as a Health Investment: How Much Should We Be Willing to Spend?

BACKGROUND

This paper examines the benefits and costs that accrue when a cadaveric organ donor is procured. We estimate the cost per quality-adjusted life year (QALY) for donor procurement. Our objective was not only to see whether organ procurement is a "good" health investment, but also to clarify how much it is worth spending to obtain additional donors.

METHODS

We calculated the average number of kidney, heart, and liver transplants that a typical cadaveric donor generates. Relying primarily on reviewing the published literature, we estimated for each organ type the average number of QALYs that transplants add and the average medical costs they generate. We multiplied per organ benefits and costs by the number of organs from the typical donor, and summed the results to calculate the cost per QALY from procuring an additional donor. We conducted extensive sensitivity analyses of the assumptions.

RESULTS

Our central estimate indicates that the typical donor generates about 13 QALYs at an added medical cost of about $214,000, a cost of approximately $16,000 per QALY. Our high estimate is approximately $57,000.

CONCLUSIONS

The implications of these findings depend upon how we choose to value QALYs. Most analysts agree that a figure of $100,000 is reasonable. At this value, the benefit obtained from one added donor would be $1.3 million (13 x $100,000) while the medical costs would be $214,000. The implication is that we should be willing to spend up to $1,086,000 ($1.3 million - $214,000) to obtain one more donor.

Renal impairment and diabetes mellitus after liver transplant

INTRODUCTION

One of the major concerns in liver transplant patients who survive past 1 year posttransplant is the development of chronic diseases.

AIM

We studied two important clinical conditions that can have a chronic course-renal impairment and diabetes mellitus-among long-term liver transplant survivors.

METHODS

All adult patients transplanted and followed for at least 1 year were evaluated for clinical status, blood tests, and imaging studies. The occurrence and development of renal impairment, defined as a serum creatinine above 125 micromol/L or creatinine clearance less than 75 mL/min, or diabetes mellitus were evaluated for contributing factors.

RESULTS

The 35 evaluated patients of mean age at transplant of 50 years had a mean follow-up duration of 45 months. The incidence of posttransplant renal impairment was 22.8% at 1 year and 47.6% at 3 years. This disorder was associated with pretransplant renal impairment and with a diagnosis of diabetes. Posttransplant diabetes mellitus was observed in 48.6% with 41.1% resolving over time.

CONCLUSION

Posttransplant renal impairment appears to be a potential long-term problem. Although this relates to pretransplant conditions, longer follow-up is required to examine whether posttransplant factors contribute to its progression.

Update on liver transplantation using cyclosporine

After the introduction of cyclosporine into liver transplantation in 1983, 1-year patient survival more than doubled. Later, with the improved microemulsified formulation of cyclosporine (Neoral) more stable pharmacokinetics were achieved. Today, C(2) monitoring of cyclosporine blood levels allows a more accurate estimation of the area under the concentration-versus-time curve as the single best indicator of cyclosporine exposure. As a consequence, with better control of side effects as well as desired effects the results of cyclosporine in liver transplantation have been further improved. The introduction of mycophenolate mofetil and basiliximab/daclizumab combination therapy has provided new options for the prevention of allograft rejection. The safety profile of individual immunosuppressive regimens comes more into focus since acute allograft rejection may be controlled successfully with competing strategies. As the focus in liver transplantation is shifting toward greatly improved long-term results, late posttransplant mortality with a functioning graft is a major concern. Prevention of long-term complications associated with highly effective immunosuppressants--posttransplant lymphoproliferative disease, cytomegalovirus infection, diabetes, hypertension, and hyperlipidemia-gains importance. Technical advances in living-related and cadaveric split-liver transplantation have lead to increasing use of segmental liver transplantation with the need to consider the effects of immunosuppression on liver regeneration and metabolism. The individualized orchestration of immunosuppression taking into account the underlying liver disease as well as other individual predispositions remains a future challenge.

Mycophenolate mofetil can be used as monotherapy late after liver transplantation

We report our experience with calcineurin inhibitor (CNI) withdrawal and MMF monotherapy in 50 adult liver transplant (OLT) recipients with CNI-related toxicity. Thirty-four patients had chronic renal dysfunction (CRD) associated with arterial hypertension, 11 had only CRD and other five patients had hypertension. The mean time between OLT and introduction of MMF was 81 months. After the introduction of MMF, CNI was progressively reduced and withdrawn if possible. At the end of the follow up (mean time: 18 months) CNI was withdrawn in 39 patients (78%), and there was a significant decrease from baseline in serum creatinine (1.81-1.49 mg/dL; p < 0.0001), BUN (76.6-52.8 mg/dL; p < 0.0001) and uric acid (9-7.5 mg/dL; p < 0.0001) levels, and an increase in creatinine clearance (44.7-55.1 mL/min; p < 0.0001). Excluding patients who developed graft rejection and two patients who died, CRD improved in 32 of 40 patients (80%), and arterial hypertension improved in 22 of 29 patients (76%). Five patients (10%) developed acute rejection, and one patient (2%) chronic rejection. Twenty-six patients (52%) experienced side-effects, with asthenia, herpes virus infection, and diarrhea being the most common. Only eight patients (16%) required MMF dose reduction. In conclusion, MMF monotherapy late after OLT improves CRD and hypertension in most patients, is safe and well tolerated.

Donor age influences 10-year liver graft histology independently of hepatitis C virus infection

BACKGROUND/AIMS

Factors influencing the long-term histological outcome of liver graft are not known. We conducted a prospective study based on a 10-year liver biopsy in order to identify the main factors influencing long-term graft histology.

METHODS

270 of 423 patients who still had their first functional graft 10 years after liver transplantation accepted to undergo routine liver biopsy. All slides were blindly reviewed by two pathologists.

RESULTS

Main histological findings were fibrosis in 143 patients (54%) and ductopenia in 76 patients (29%). Ductopenia was independently related to higher donor age (32+/-12 vs 28+/-13 years; P<0.02). Severity of fibrosis was influenced by hepatitis C virus (HCV) infection (P<0.001), hepatitis B virus (HBV) recurrence (P=0.001) and higher donor age (P=0.03). Eighty biopsies (30%) showed minimal-change lesions which were associated with the absence of HCV infection (24/80 vs 99/185; P<0.001) or of HBV infection (1/80 vs 15/185; P=0.03) and lower donor age (25+/-11 vs 31+/-13 years; P<0.001).

CONCLUSIONS

Post-transplant infection by HCV or HBV are main factors influencing the histological course of liver graft. Donor age was also a strong factor in HCV infected patients as well as in HCV-negative patients. This variable should be taken into account, particularly for candidate recipients with long life expectancy.

Role of liver transplantation for hepatobiliary malignant disorders

The role of liver transplantation for hepatobiliary malignant disorders remains controversial and will remain so until several crucial issues are resolved, the main difficulty being the shortage of organ donors. Furthermore, a consensus needs to be reached within the transplantation community on the tumour stage at which each disorder is too advanced to be salvaged by liver transplantation. Despite these limitations, there are generally accepted criteria that define when transplantation can, and should, be offered for hepatobiliary malignant disorders.

Hepatic artery embolization for treatment of patients with hereditary hemorrhagic telangiectasia and symptomatic hepatic vascular malformations

At present there is no established therapy for treating patients with hereditary hemorrhagic telangiectasia (HHT) and symptomatic hepatic involvement. We present the results of a prospective study with 15 consecutive patients who were treated with staged hepatic artery embolization (HAE). Branches of the hepatic artery were selectively catheterized and embolized in stages using polyvinyl alcohol particles (PVA) and platinum microcoils or steel macrocoils. Prophylactic antibiotics, analgesics and anti-emetics were administered after every embolization. Clinical symptomatology and cardiac output were assessed before and after therapy as well as at the end of follow-up (median 28 months; range 10-136 months). Five patients had abdominal pain and four patients had symptoms of portal hypertension. The cardiac output was raised in all patients, with cardiac failure being present in 11 patients. After treatment, pain resolved in all five patients, and portal hypertension improved in two of the four patients. The mean cardiac output decreased significantly ( P<0.001) from 12.57+/-3.27 l/min pre-treatment to 8.36+/-2.60 l/min at the end of follow-up. Symptoms arising from cardiac failure resolved or improved markedly in all but one patient. Cholangitis and/or cholecystitis occurred in three patients of whom two required a cholecystectomy. One patient with pre-existent hepatic cirrhosis died as a complication of the procedure. Staged HAE yields long-term relief of clinical symptoms in patients with HHT and hepatic involvement. Patients with pre-existing hepatic cirrhosis may be poor candidates for HAE.

Evaluation of centre and period effects in allogeneic haematopoietic stem cell transplantation in France

We evaluated the effect of individual and collective factors on the outcome of allogeneic haematopoietic stem cell transplantation (HSCT) at 35 French centres. Individual factors included patient and transplantation characteristics. Collective factors were related to the period and centre in which HSCT was performed. Two centre factors were studied: centre experience (ie number of HSCT performed during the study period) and the type of centre (paediatric or adult). All patients receiving a first allogeneic HSCT in France between 1st January 1993 and 31st December 1997 were included in the study. The follow-up period ended on 31st December 1997. The final sample included 2756 subjects. We analysed overall survival (OS) and transplant-related mortality (TRM). Prognostic factors were identified by univariate and multivariate analysis, using Cox models. We found that centre experience had no significant effect on outcome. However, survival rates, whether determined on the basis of OS or TRM, were significantly higher in paediatric centres than in adult centres. Residual heterogeneity was found between adult centres. Survival rates were significantly higher for HSCT performed after 1st January 1996 than for those performed before this date.

Renal function after liver transplantation: calcineurin inhibitor nephrotoxicity

Renal failure, mainly due to calcineurin inhibitor (CNI) nephrotoxicity, is the most common complication following orthotopic liver transplantation (ltx). The aim of this study was to evaluate the incidence and course of renal failure in adult ltx patients. Severe acute renal failure in early postoperative period due to impaired hemodynamics and CNI nephrotoxicity, occurred in 14 patients, 3 of whom required dialysis. The creatinine clearance after ltx showed a tendency to decrease, but there was no statistically significant difference (P >.05) in the change in serum creatinine clearance levels between patients treated with tacrolimus (TAC) versus Cyclosporine (CsA) during the first 2 years of follow-up. Fourteen patients required conversion of their regimen because of CNI nephrotoxicity namely, dose reduction (n = 7) or discontinuation of CNI therapy with the replacement by mycophenolate mofetil (MMF) (n = 5) or SRL (n = 5). Dose reduction or CNI withdrawal significantly improved the creatinine clearance (P <.05) without affecting lives graft function. No episode of acute rejection was observed after conversion. Neither conversion of CsA to TAC nor the reverse maneuver significantly influenced the serum creatinine level (P >.05). Reduction of the CNI dose or CNI discontinuation or replacement with MMF or SRL in patients with stable liver but impaired renal function is safe, resulting in a significant improvement in renal function.

Survival after liver transplantation in the United States: a disease-specific analysis of the UNOS database

Our goal was to describe disease-specific survival and the clinical variables that predict survival in a large national cohort of adult liver transplant recipients. Data on 17,044 adult patients who received an initial orthotopic liver transplant between 1990 and 1996 with follow-up through 1999 was obtained from the United Network for Organ Sharing (UNOS). Disease-specific Kaplan-Meier survival plots and Cox Proportional Hazards models were estimated, and differences in the clinical characteristics of patients at the time of transplantation by disease were examined. Overall posttransplant survival currently exceeds 85% in the first year and is approaching 75% at 5 years. Unadjusted Kaplan-Meier survival is improved for recipients who are younger, female, and in better clinical condition. Survival is a function of disease and level of illness: cancer, fulminant liver failure, alcoholic liver disease, and the hepatitidies have the poorest prognosis, while primary billiary cirrohsis and sclerosing cholangitis have the best. Recipients who were outpatients before transplantation have longer survival than those transplanted from the hospital or intensive care unit. Although the model for end-stage liver disease (MELD) score was designed to predict pretransplant survival, patients with higher MELD scores have poorer posttransplant survival, but the MELD score is less predictive than the specific disease. Differences in disease-specific survival are partially explained by differences in disease severity at the time of transplantation. In conclusion, Disease-specific survival models indicate that there remains tremendous variability in survival as a function of underlying liver disease. However, a significant portion of the difference in survival between diseases arises from differences in clinical characteristics at the time of transplantation.

Studies of Pediatric Liver Transplantation 2002: patient and graft survival and rejection in pediatric recipients of a first liver transplant in the United States and Canada

Studies of Pediatric Liver Transplantation (SPLIT) is a cooperative research network comprising 38 pediatric liver transplant centers in North America. Data from the 1092 patients who have received a first liver transplant since 1995 were analyzed for factors influencing patient survival, graft survival and acute rejection. The 3, 12, 24 and 36 month Kaplan-Meier estimates of patient/graft survival were 90.9/85.5, 86.3/80.2, 84.3/76.0, and 83.8/75.3% respectively. Univariate analysis identified initial diagnosis, type of graft (whole vs. living and cadaveric technical variant), growth failure and continuous hospitalization or ICU admission prior to transplantation as significantly influencing patient and graft survival. Subsequent multivariate analysis identified as risk factors for death: fulminant liver failure (RR = 3.05, p < 0.05), cadaveric technical variant grafts (RR = 1.95, p < 0.05), continuous hospitalization pre-transplant (RR = 1.79, p < 0.05), height deficit >2 s.d. from mean (RR = 3.22, p < 0.05). Risk factors for graft loss included: fulminant liver failure (RR = 2.27, p < 0.05), cadaveric technical variant grafts, (RR = 1.97, p < 0.05). Eleven percent of the 1092 patients were re-transplanted; vascular complications, particularly hepatic artery thrombosis (8.3% overall; 36.3% of graft failures), were responsible for the majority of re-transplants. Infection was the single most important cause of death (40 of 141, 28.4%) and was a contributing cause in 55 (39%), particularly with bacterial or fungal organisms. The cumulative Kaplan-Meier estimates of first rejection at 3, 12, 24 and 36 months were 44.8, 52.9, 59.1, and 60.3%. Initial immunosuppression with tacrolimus reduced the probability of rejection (RR = 0.62, p < 0.05). Eleven percent of rejections were steroid-resistant; chronic rejection led to 7 of 121 (5.8%) re-transplants. The SPLIT registry, in compiling data from a large number of centers, reflects the current outcomes for pediatric liver transplants in North America.

Identification of transforming growth factors actively transcribed during the progress of liver fibrosis in biliary atresia

BACKGROUND/PURPOSE

Transforming growth factor-beta (TGF-beta) 1 and 2 and their receptors TbetaR-I, TbetaR-II, and TbetaR-III are powerful profibrogenic mediators in the body. Their expression has not been completely elucidated in the progress of liver fibrosis associated with biliary atresia (BA).

METHODS

The authors compared the cytokine expression in the liver of 3 patients with BA at Kasai's procedure (KP) and in 3 patients at liver transplantation (LT). Two liver samples from children with no liver disorders served as normal controls (CO). Real-time quantitative reverse transcriptase polymerase chain reaction (QRT-PCR) was used to confirm the findings of relative mRNA expression of TGF-beta1 and 2 and their receptors. An immunohistochemistry and an enzyme-linked immunoassay (ELISA) were used to localize the liver cells that express TGF-beta2 and to quantitate the protein expression among groups.

RESULTS

Compared with controls, both TGF-beta1 and TGF-beta2 mRNA expression increased in the liver during the progress of liver fibrosis in patients with KP and LT on the array. Only TGF-beta2 showed a significant increase in expression in LT compared with KP and CO (P =.001 for TGF-beta2 and P = 0.054 for TGF-beta1). Both TbetaR-I and TbetaR-II showed no significant change among groups; TbetaR-III decreased significantly in LT compared with CO (P =.011). TGF-beta2 immunostaining was mainly localized in the bile duct epithelium and was remarkably higher in LT in which the proliferating bile ductules and the hepatocytes contributed to the increase in immunostaining and possibly to significantly higher plasma TGF-beta2 protein levels in LT than in KP.

CONCLUSIONS

This study identified TGF-beta2 as the most actively transcribed TGF-beta gene during the progress of liver fibrosis in BA and found a reciprocal relationship of upregulation of TGF-beta2 with downregulation of TbetaR-III in LT.

Comparative analysis of outcome following liver transplantation in US veterans

The purpose of this study was to evaluate whether there was a difference in mortality following orthotopic liver transplantation (OLT) in a US veteran (VA) population (n = 149) compared to a non-VA (university) population (n = 285) and what factors could explain this difference. Survival following OLT for 149 VA patients was compared with that of 285 university patients. By Kaplan-Meier survival analysis, VA patients had higher mortality than university patients with respective 1-year, 3-year, and 5-year survival of 82%, 75%, and 68% vs. 87%, 82%, and 78% (p = 0.006). Gender, etiology of end-stage liver disease (ESLD) and donor age (i.e. older than 34 years) also significantly influenced survival. However, when donor and recipient age, gender, model for end-stage liver disease (MELD) score, and etiology of liver disease were included with hospital status in a multivariate Cox proportional hazards model, the VA population did not have higher mortality. A final model to predict mortality following transplantation was derived for all 434 patients where individuals were assigned risk scores based on the equation R = 0.219 (gender) + 0.018 (donor age) + 0.032 (recipient age) + 0.021 (MELD), where recipient age, donor age, and MELD score are the respective continuous variables and gender = 1 (men) and 0 for women (c-statistic = 0.71).

Estrogen receptor-alpha, sexual dimorphism and reduced-size liver ischemia and reperfusion injury in mice

Estrogen (E(2)) exerts its effect on target organs principally by interacting with specific estrogen receptors (ER) such as ER-alpha or ER-beta. The role that these E(2) receptors play in mediating the protective effects observed in RSL+I/R induced injury remains to be defined. To study the role of ER-alpha, we anesthetized female and male wild type (wt; C57Bl/6) and ER-alpha-deficient (alphaERKO) mice and subjected them to 70% liver ischemia for 45 min followed by resection of the remaining 30% nonischemic lobes and reperfusion of the ischemic tissue. For some experiments, wt and alphaERKO male mice were injected with E(2). Survival was monitored on a daily basis while liver injury was assessed by quantifying serum alanine aminotransferase (ALT) levels and histopathology. Hepatic eNOS mRNA levels were evaluated using semi-quantitative RT-PCR. Our data showed that untreated females or males treated with E(2) survived RSL+I/R surgery indefinitely whereas all male mice given vehicle died within 3-5 days following surgery. This protective effect was diminished in alphaERKO female mice such that only 40% of alphaERKO females survived 7 d following RSL+I/R. Furthermore, liver injury was significantly higher in alphaERKO females compared with their wt counterparts and similar to those seen in wild type males and alphaERKO males. The protective effect observed in wild type females or E(2) treated males correlated well with increases in hepatic eNOS message whereas both male and female alphaERKO mice exhibited significantly lower levels of eNOS mRNA. We conclude that this protection may in part be due to the E(2)/ER-alpha-mediated activation of eNOS.

Predictive factors for early mortality following liver transplantation

AIMS

To retrospectively review our liver transplant performance to identify factors that influenced early outcomes and to prospectively test their validity in predicting outcomes.

METHODS

Clinical records from 190 patients with liver transplants (LT; n = 200) performed between 1991 and 1997 were reviewed and the data evaluated by univariate and multivariate analyses regarding clinical outcome. The prognostic model thus obtained was prospectively evaluated in 55 patients undergoing transplant between 1999 and 2000.

RESULTS

Main indication for transplant was post-necrotic cirrhosis (61%), mostly HCV(+). The majority of patients were Child-Pugh C status (46%). Post-operative mortality at 3 months was 15.3%. Risk factors predicting death were: Child-Pugh C status (OR 1.3), pre-LT renal insufficiency (OR 5.8), malnutrition (OR 2.9) and technically complex surgery requiring cross-clamping with or without bypass (OR 4.9). None of the donor factors was significant. Prospectively applied to predict outcome in the 55 patients, the model had a sensitivity of 80% and a specificity of 88.8% with a higher-than-anticipated accuracy with a positive predictive value of 61.5% and a negative predictive value of 95.3%.

CONCLUSIONS

Pre-LT renal insufficiency is the most significant risk factor for early mortality and suggests that LT should be performed before evidence of irreversible renal insufficiency becomes manifest.

Vasopressor agents without volume expansion as a safe alternative to venovenous bypass during cavaplasty liver transplantation

BACKGROUND

Cavaplasty orthotopic liver transplantation (OLT) offers advantages for hepatectomy and implantation and eliminates the risk of outflow obstruction. However, it does require clamping of the cava. This study describes the use of a vasopressor without fluid expansion or venovenous bypass (VB) for hemodynamic control during the anhepatic phase.

METHODS

The cavaplasty OLT technique was used routinely. A vasopressor was administered if the mean arterial blood pressure (MAP) was less than 60 mm Hg after clamping of the cava. If the MAP did not reach 60 mm Hg after adjusting the dosage of the vasopressor, femoro-axillary VB would be used. VB was also indicated for preexisting cardiac disease or for massive hemorrhage from severe portal hypertension and extensive adhesions.

RESULTS

Among all the 121 adult cavaplasty OLTs, 33 were supported with VB and 50 received a vasopressor. The remaining 38 were excluded. However, baseline variables were well matched, except that preexisting cardiac disease was more frequent in the VB group. The median dosage of epinephrine was 0.07 microg/kg/min (range 0.01-0.6). The VB and vasopressor groups were similar in the reduction in mean MAP and the accumulation in arterial lactate upon clamping as well as in the central venous pressure upon unclamping. Postreperfusion hypotension was more frequent in the VB than in the vasopressor group (27.3% vs. 4.0%, P=0.006). There was no primary graft nonfunction or intraoperative right heart failure. One patient in the vasopressor group required postoperative temporary dialysis. Ninety-day patient and graft survival for the VB and vasopressor groups were 97.0% vs. 98.0% and 97.0% vs. 94.0%, respectively.

CONCLUSION

Modest doses of vasopressor without volume expansion or VB can maintain hemodynamic stability during the anhepatic phase of cavaplasty OLT.

Results of retransplantation for recurrent hepatitis C

Retransplantation for recurrent hepatitis C virus (HCV) has been evaluated in small series. In this study, patients undergoing transplantation for HCV-related cirrhosis with subsequent retransplantation more than 90 days for recurrent HCV (proven by pathologic examination of the explant and exclusion of other factors) were prospectively followed. This group was compared with a simultaneous cohort without HCV infection undergoing retransplantation more than 90 days after primary transplantation. Forty-two patients underwent retransplantation for recurrent HCV with a median survival of 12.9 +/- 6.7 months after retransplantation. Twenty patients (48%) were dead at 6 months, and 13 (65%) of these deaths were due to sepsis. On univariate analysis, creatinine level greater than or equal to 3 mg/dL, platelet count less than 100000/microL, prothrombin time (PT) greater than or equal to 16 seconds, alkaline phosphatase level less than or equal to 240 U/L, gamma-glutamyltransferase level less than or equal to 130 U/L, and donor age of 60 years or greater all correlated significantly with shorter survival after retransplantation. PT and donor age were predictors of survival on multivariate analysis. Patients undergoing retransplantation for recurrent HCV had a significantly shorter median survival than the 55 patients undergoing retransplantation for other chronic reasons of graft loss (75.6 +/- 17.7 months). In conclusion, median survival after liver retransplantation for recurrent HCV is significantly shorter than after retransplantation for other causes of late graft loss. Most deaths occur in the first 6 months and are due to sepsis. Candidates for retransplantation with a preoperative PT less than 16 seconds and those receiving grafts from donors younger than 60 years can expect a significantly longer median survival after retransplantation.

Epidemiology and results of liver transplantation for acute liver failure in Chile

Acute liver failure (ALF) is a severe, life-threatening condition associated with a high mortality rate. The objective of this study is to present the experience of a Chilean liver transplant program with orthotopic liver transplantation (OLT) for ALF. All patients with the diagnosis of ALF evaluated in our program between January 1995 and May 2003 were included in the analyses of etiology and outcomes. Candidates for OLT activated on a national waiting list were transplanted with cadaveric or living-related donor (LRD) organs. Twenty-seven patients age 1 to 19 years (median, 7.4 years) were transplanted at a median weight of 30.7 kg including 17 cadaveric and 10 with LRD livers. Most frequent etiologies were hepatitis A in 10 cases (37%) and unknown in 12 (48.1%). One donor experienced superficial phlebitis. Four patients were retransplanted (14.8%). Twenty patients are alive with 1- and 5-year survival rates of 74.1% At a median follow up of 34 months (range = 2 to 120). Seven patients died due to sepsis, multiorganic failure, graft primary nonfunction, intracranial hemorrhage, and intraoperative cardiac arrest. This experience revealed results comparable to international reports, allowing survival of patients destined to die.

Retransplantation for recurrent hepatitis C: the argument against

1. Cirrhosis from chronic hepatitis C is the most common indication for liver grafting today. The course of hepatitis C is accelerated after liver transplantation, and no current therapy reliably prevents or arrests it. 2. It is anticipated that 20% or more of hepatitis C virus-positive transplant recipients will develop allograft cirrhosis, and the only solution will be retransplantation. 3. Results of retransplantation are inferior to primary transplantation. 4. Recipient risk factors that adversely affect mortality after repeated liver grafting include age older than 50 years, renal insufficiency, and severity of hyperbilirubinemia. When present, they reduce survival after retransplantation to approximately 40% or less. 5. Retransplantation on a large scale for recurrent hepatitis C is problematic from the perspectives of outcome, resource utilization, and fairness to candidates awaiting primary grafts.

Outcomes of orthotopic liver transplantation in Chile

Our liver transplant program was started in 1993 in a private clinic and a public hospital. Thereafter, a rapid increase in adults and pediatric candidates for this therapeutic option lead to this analysis of results in 165 orthotopic liver transplants (OLT) in 143 patients between November 1993 and December 2002. Seventy-four OLT were performed in 66 adult patients and 91 in the pediatric group. Liver grafts came from cadaveric donors in 145 cases (74 adults and 71 children). The technique of living-related donor was utilized in 20 pediatric cases. Main indications for OLT in the adult group were HCV cirrhosis, primary biliary cirrhosis; biliary atresia and acute liver failure were the indications in pediatric patients. Retransplantation was needed for 23 patients, including 9 adults and 14 children. The most frequent causes of death were sepsis, graft primary nonfunction, and vascular complications. Actuarial survivals at 1 and 5 years were 80.7% and 72.6% for the adult group and 82% and 74.8% for the pediatric group, respectively. Our results are comparable to those published by large, experienced, international centers, with much better financial support.

Microbubble ultrasound contrast in the assessment of hepatic artery patency following liver transplantation: role in reducing frequency of hepatic artery arteriography

We prospectively evaluated the role of microbubble ultrasound contrast for detection of hepatic artery thrombosis following liver transplantation. The hepatic artery of adult liver transplant recipients with suspected thrombosis on surveillance Doppler ultrasound (US) were re-examined by a second observer. In patients with no hepatic spectral Doppler signal the microbubble contrast agent Levovist was used. The presence or absence of flow following microbubble contrast was evaluated against arteriography or repeated Doppler US findings. A total of 794 surveillance Doppler US examinations were performed in 231 patients. Hepatic artery flow was demonstrated in 759 of 794 (95.6%) examinations. Microbubble ultrasound contrast was administered in 31 patients (35 studies) with suspected hepatic artery thrombosis. Following microbubble US contrast the hepatic artery could not be demonstrated in 13 of 35 (37.1%) studies (12 patients). Eight patients had arteriography: there was hepatic artery thrombosis in 7 patients and 1 patient had a patent, highly attenuated artery. Detection of a patent hepatic artery increased from 759 of 794 (95.6%) to 781 of 794 (98.4%) with the addition of microbubble contrast. Upon independent reading of the data, the degree of operator confidence in the assessment of the hepatic artery patency prior to microbubble contrast was 4.7 (CI 1.92-7.5) but rose to 8.45 (CI 7.06-9.84) following microbubble contrast ( p<0.0001). In 22 of 35 (62.9%) of studies arteriography could potentially have been avoided. Ultrasound microbubble contrast media may reduce the need for invasive arteriography in the assessment of suspected hepatic artery thrombosis.

The impact of experience of a transplantation center on the outcomes of orthotopic liver transplantation

The so-called learning factor has been disregarded for many years in analyzing the causes of surgical complications and post-operative mortality; it is also the case for OLT. In our center until April 2003, 209 OLT were performed in 196 patients. We evaluated the impact of experience of the transplantation team on the outcomes of liver transplantation. Thirty-four patients died (mortality rate, 16%) and 1-year survival rate, 64%. Mortality rates varied during different periods of observation due to increasing experience of the transplantation team. The causes of mortality were assessed for a series of 34 patients: it was 75% at the beginning of transplantation procedures while recent deaths have not recently exceeded 10% of cases.