Outcome of liver transplantation in hepatitis C virus-infected patients who received hepatitis C virus-infected grafts

Donor Viral Hepatitis and Liver Transplantation

Despite increasing numbers of organ transplants completed each year, there continues to be an organ shortage in liver transplantation. This has led to the utilization of previously discarded or "marginal" allografts, such as those from donors with hepatitis C virus (HCV) or hepatitis B virus (HBV). The advent of direct acting antivirals and nucleos(t)ide analogs has allowed these allografts to be safely transplanted regardless of the recipients' hepatitis status with comparable graft and patient survival. Recent advances have even allowed usage of actively viremic donors with similar graft and patient outcomes. This article presents an overview of the use of HCV positive and HBV positive allografts.

The current status of virus-positive liver transplantation

PURPOSE OF REVIEW

The last 2 years have seen significant developments in virus-positive liver transplantation. This review provides an updated account of the transplantation of hepatitis C virus (HCV), hepatitis B virus (HBV) and HIV-positive livers, with a specific focus on studies published in the last 18 months.

RECENT FINDINGS

The advent of highly efficacious direct acting antiviral agents, nucleos(t)ide analogues and a continued organ shortage have led to the well tolerated utilization of HCV, HBV and HIV-positive organs. There has been a significant increase in the transplantation of HCV seropositive and NAT+ organs into HCV-negative recipients, without compromising patient or graft survival. Early reports of HBV core antibody (HBVcAb), HBV surface antigen (HBVsAg) positive and NAT+ donors are growing in the USA with promising results. Similarly, small studies have described the use of HIV-positive to HIV-positive liver transplantation without concerns for superinfection.

SUMMARY

HCV, HBV and HIV-positive liver transplantations can be accomplished safely and are associated with equivalent outcomes when paired with appropriate recipients. The practice of virus positive liver transplantation should be encouraged to combat the ongoing organ shortage.

Hepatitis C-positive liver transplantation: outcomes and current practice

PURPOSE OF REVIEW

The coincidence of the opioid epidemic and the approval of direct-acting antivirals for the treatment of hepatitis C virus (HCV) has resulted in an imbalance in HCV viraemic donors relative to HCV viraemic patients awaiting liver transplantation. Although ethical concerns exist about knowingly infecting patients with HCV in the absence of prospective, protocolized studies, transplantation of HCV-positive liver allografts into HCV-negative recipients has increased exponentially in recent years. For this reason, we sought to review outcomes, cost-effectiveness and ethical concerns associated with this practice.

RECENT FINDINGS

Short-term outcomes in terms of patient and graft survival are equivalent to those who received HCV-negative allografts without an increase in acute rejection, biliary or vascular complications. Few cases of treatment failure have been reported and complications related to the virus itself such as fibrosing cholestatic hepatitis and membranous glomerulonephritis are rare and reversible with prompt direct-acting antiretroviral treatment. The practice appears cost-effective and modelling suggests a survival benefit for patients willing to accept HCV-positive organs compared with those who do not.

SUMMARY

In light of the preponderance of current data, one could argue it is unethical to withhold HCV-positive grafts from HCV-negative recipients who have undergone thorough informed consent.

Immediate administration of antiviral therapy after transplantation of hepatitis C-infected livers into uninfected recipients: Implications for therapeutic planning

The practice of transplanting hepatitis C (HCV)-infected livers into HCV-uninfected recipients has not previously been recommended in transplant guidelines, in part because of concerns over uncontrolled HCV infection of the allograft. Direct-acting antivirals (DAAs) provide an opportunity to treat donor-derived HCV-infection and should be administered early in the posttransplant period. However, evidence on the safety and efficacy of an immediate DAA treatment approach, including how to manage logistical barriers surrounding timely DAA procurement, are required prior to broader use of HCV-positive donor organs. We report the results of a trial in which 14 HCV-negative patients underwent successful liver transplantation from HCV-positive donors. Nine patients received viremic (nucleic acid testing [NAT]-positive) livers and started a 12-week course of oral glecaprevir-pibrentasvir within 5 days of transplant. Five patients received livers from HCV antibody-positive nonviremic donors and were followed using a reactive approach. Survival in NAT-positive recipients is 100% at a median follow-up of 46 weeks. An immediate treatment approach for HCV NAT-positive liver transplantation into uninfected recipients is safe and efficacious. Securing payer approval for DAAs early in the posttransplant course could enable need-based allocation of HCV-positive donor organs irrespective of candidate HCV status, while averting chronic HCV allograft infection.

Recent advances in liver transplantation with HCV seropositive donors

The paradigm shift from interferon-based to direct-acting antiviral (DAA) therapy for the treatment of hepatitis C virus (HCV) infection has revolutionized the field of liver transplantation. These advances in effective HCV treatment, along with the persistent shortage in available liver grafts, have encouraged investigators to assess the need for adopting more inclusive donor policies. Owing to the poor outcomes following liver transplantation with recurrent HCV infection, liver transplantation using HCV seropositive donors (non-viremic and viremic) had been restricted. However, as a result of the growing supply of HCV seropositive donors from the recent opioid epidemic along with the advent of efficacious DAA therapy to treat HCV recurrence, there has been an increasing trend to use HCV seropositive donors for both HCV seropositive and seronegative recipients. The review aims to discuss recent advances and associated outcomes related to the use of HCV seropositive grafts for liver transplantation.

Liver, simultaneous liver-kidney, and kidney transplantation from hepatitis C-positive donors in hepatitis C-negative recipients: A single-center study

Transplantation of organs from hepatitis C virus (HCV)-antibody (Ab) and -nucleic acid test (NAT) positive donors into HCV-negative recipients has been proposed to expand the donor pool and shorten waiting times. Data on early single-center outcomes are lacking. Nineteen liver (LT, including seven simultaneous liver-kidney [SLKT]) and 17 kidney transplant (KT) recipients received organs from HCV (+) donors; of these, 13 were HCV NAT (+) in each group. All patients who received organs from HCV NAT (+) donors developed HCV viremia post-transplant except for 2 KT recipients. Patients were treated with a variety of direct-acting antiviral regimens, with high rates of sustained virologic response among those with at least 12 weeks of follow-up past the end of treatment: 12/13 (92%) and 8/8 (100%) among LT/SLKT, and KT recipients. Median time to treatment start was 42 days (interquartile range [IQR] 35-118 days) and 40 days (IQR 26-73) post-LT/SLKT and KT, respectively. One death occurred in a SLKT recipient unrelated to HCV or its treatment. There was no significant increase in rejection, proteinuria, or changes in immunosuppression in any group. Organs from HCV-viremic donors can be utilized for HCV-uninfected recipients with good short-term outcomes.

Expanding the donor pool: Hepatitis C, hepatitis B and human immunodeficiency virus-positive donors in liver transplantation

Liver transplantation (LT) remains the best option for patients with end-stage liver disease but the demand for organs from deceased donors continues to outweigh the available supply. The advent of highly effective anti-viral treatments has reduced the number of patients undergoing LT for hepatitis C (HCV) and hepatitis B (HBV) related liver disease and yet the number of patients waiting for LT continues to increase, driven by an increase in the patients listed with a diagnosis of cirrhosis due to non-alcoholic steatohepatitis and alcohol-related liver disease. In addition, human immunodeficiency virus (HIV) infection, which was previously a contra-indication for LT, is no longer a fatal disease due to the effectiveness of HIV therapy and patients with HIV and liver disease are now developing indications for LT. The rising demand for LT is projected to increase further in the future, thus driving the need to investigate potential means of expanding the pool of potential donors. One mechanism for doing so is utilizing organs from donors that previously would have been discarded or used only in exceptional circumstances such as HCV-positive, HBV-positive, and HIV-positive donors. The advent of highly effective anti-viral therapy has meant that these organs can now be used with excellent outcomes in HCV, HBV or HIV infected recipients and in some cases uninfected recipients.

Use of Hepatitis C-Positive Liver Grafts in Hepatitis C-Negative Recipients

As the demand for liver transplantation continues to rise, the scarcity of liver donor grafts has led to the use of extended criteria grafts for liver transplantation in select group of patients. Hepatitis C-seropositive liver grafts have been used primarily in hepatitis C-positive recipients, with studies showing non-inferior outcomes when compared to hepatitis C-negative grafts. Studies suggest that hepatitis C serology status of the donor liver does not influence the patient or graft outcomes in the recipient. These results advocate for offering hepatitis C-positive grafts to all patients awaiting liver transplantation regardless of their hepatitis C status. However, some concerns persist regarding the ethics of potentially introducing a new infection into a patient that could progress to chronic liver disease following liver transplantation. The recent approval of direct-acting antiviral therapy offers a solution to this dilemma, as it has changed the landscape of hepatitis C management by making it a curable disease. In this review, we shall discuss the current evidence regarding the use of hepatitis C-seropositive donor grafts in hepatitis C-positive and hepatitis C-negative patients.

Donor-derived Viral Infections in Liver Transplantation

Donor-derived infections are defined as any infection present in the donor that is transmitted to 1 or more recipients. Donor-derived infections can be categorized into 2 groups: "expected" and "unexpected" infections. Expected transmissions occur when the donor is known to have an infection, such as positive serology for cytomegalovirus, Epstein Barr virus, or hepatitis B core antibody, at the time of donation. Unexpected transmissions occur when a donor has no known infection before donation, but 1 or more transplant recipients develop an infection derived from the common donor. Unexpected infections are estimated to occur in far less than 1% of solid organ transplant recipients. We will review the epidemiology, risk factors, and approaches to prevention and management of donor-derived viral infectious disease transmission in liver transplantation.

Infectious Disease Transmission in Solid Organ Transplantation: Donor Evaluation, Recipient Risk, and Outcomes of Transmission

In 2016, the Transplantation Society of Australia and New Zealand, with the support of the Australian Government Organ and Tissue authority, commissioned a literature review on the topic of infectious disease transmission from deceased donors to recipients of solid organ transplants. The purpose of this review was to synthesize evidence on transmission risks, diagnostic test characteristics, and recipient management to inform best-practice clinical guidelines. The final review, presented as a special supplement in Transplantation Direct, collates case reports of transmission events and other peer-reviewed literature, and summarizes current (as of June 2017) international guidelines on donor screening and recipient management. Of particular interest at the time of writing was how to maximize utilization of donors at increased risk for transmission of human immunodeficiency virus, hepatitis C virus, and hepatitis B virus, given the recent developments, including the availability of direct-acting antivirals for hepatitis C virus and improvements in donor screening technologies. The review also covers emerging risks associated with recent epidemics (eg, Zika virus) and the risk of transmission of nonendemic pathogens related to donor travel history or country of origin. Lastly, the implications for recipient consent of expanded utilization of donors at increased risk of blood-borne viral disease transmission are considered.

Infections in Liver Transplantation

Liver transplantation has become an important treatment modality for patients with end-stage liver disease/cirrhosis, acute liver failure, and hepatocellular carcinoma. Although surgical techniques and immunosuppressive regimens for liver transplantation have improved significantly over the past 20 years, infectious complications continue to contribute to the morbidity and mortality in this patient population. The use of standardized screening protocols for both donors and recipients, coupled with targeted prophylaxis against specific pathogens, has helped to mitigate the risk of infection in liver transplant recipients. Patients with chronic liver disease and cirrhosis have immunological deficits that place them at increased risk for infection while awaiting liver transplantation. The patient undergoing liver transplantation is prone to develop healthcare-acquired infections due to multidrug-resistant organisms that could potentially affect patient outcomes after transplantation. The complex nature of liver transplant surgery that involves multiple vascular and hepatobiliary anastomoses further increases the risk of infection after liver transplantation. During the early post-transplantation period, healthcare-acquired bacterial and fungal infections are the most common types of infection encountered in liver transplant recipients. The period of maximal immunosuppression that occurs at 1–6 months after transplantation can be complicated by opportunistic infections due to both primary infection and reactivation of latent infection. Severe community-acquired infections can complicate the course of liver transplantation beyond 12 months after transplant surgery. This chapter provides an overview of liver transplantation including indications, donor-recipient selection criteria, surgical procedures, and immunosuppressive therapies. A focus on infections in patients with chronic liver disease/cirrhosis and an overview of the specific infectious complications in liver transplant recipients are presented.

Use of hepatitis C-positive grafts in hepatitis C-negative liver transplant recipients is cost effective

BACKGROUND

The number of patients needing liver transplantation (LT) exceeds the number of available allografts. The current opioid epidemic in this country has increased the number of potential donors infected with hepatitis C (HCV).

METHODS

We assessed the incremental cost-effectiveness ratio (ICER) by comparing the costs and number of liver transplants performed using HCV-positive and HCV-negative grafts into patients without HCV infection in a decision analysis model with a 1-year time horizon.

RESULTS

The use of HCV-positive grafts was found to have an ICER below $50 000 across all MELD scores. Using our baseline cohort with a model for end-stage liver disease (MELD) score of 15-22, the ICER was $21 233/additional LT performed. As the MELD scores increased, the ICER decreased. Above a MELD score of 23, the use of HCV-positive grafts became cost saving (-$115 419). Our model was robust to all variables tested in the sensitivity analyses, except drug costs.

CONCLUSION

The results of our decision analysis model highlight the potential pharmacoeconomic benefit of utilizing HCV-positive grafts in LT candidates who are not infected with HCV. The use of HCV-positive grafts is at least cost effective and even cost saving in patients with MELD scores above 23.

Hepatitis C genotype change after transplantation utilizing hepatitis C positive donor organs

A shortage in organs for transplantation has led to the increased use of hepatitis C (HCV) infected donor organs for solid organ transplant recipients infected with HCV. However, the donor HCV genotype is not routinely checked or known prior to transplant. Here, we report 4 cases of genotype conversion after transplantation in patients receiving HCV infected donor organs. This change in genotype may potentially impact HCV progression as well as treatment choice for these patients.

The American Society of Transplantation Consensus Conference on the Use of Hepatitis C Viremic Donors in Solid Organ Transplantation

The availability of direct-acting antiviral agents for the treatment of hepatitis C virus (HCV) infection has resulted in a profound shift in the approach to the management of this infection. These changes have affected the practice of solid organ transplantation by altering the framework by which patients with end-stage organ disease are managed and receive organ transplants. The high level of safety and efficacy of these medications in patients with chronic HCV infection provides the opportunity to explore their use in the setting of transplanting organs from HCV-viremic patients into non-HCV-viremic recipients. Because these organs are frequently discarded and typically come from younger donors, this approach has the potential to save lives on the solid organ transplant waitlist. Therefore, an urgent need exists for prospective research protocols that study the risk versus benefit of using organs for hepatitis C-infected donors. In response to this rapidly changing practice and the need for scientific study and consensus, the American Society of Transplantation convened a meeting of experts to review current data and develop the framework for the study of using HCV viremic organs in solid organ transplantation.

Pros and Cons: Usage of organs from donors infected with hepatitis C virus - Revision in the direct-acting antiviral era

Should organs from hepatitis C antibody positive donors (HCVD+) be used for transplantation? Organ shortage forces transplant teams to use donors with extended criteria. The decision to transplant a HCVD+ graft is a balance between the risk of transmission of a virus that could lead to end-stage liver diseases and the benefit of access to transplantation, specifically in patients with life-threatening disease. The other issue is the impact of HCV-related liver fibrosis in the donor graft on the long-term outcome in the recipient. Thus, the use of HCVD+ demonstrated a shorter meantime on the waiting list in kidney transplantation. When a HCVD+ graft is transplanted, the risk of HCV transmission depends on; 1) the quality of screening of the donor; 2) the presence of viral replication in the donor at the time of transplantation and the ability to detect it; and 3) the HCV status of the recipient but also the type of transplanted organ. In liver transplantation, the use of HCVD+ graft is usually restricted to recipients with a chronic HCV infection. Several reports showed some competition between HCV donor and recipient strain without deleterious impact on graft and patient survival. Controversies are still pending regarding the quality of the graft and the progression of fibrosis. The recent approval of direct-acting antiviral agents (DAA) dramatically changes the landscape of HCV infection treatment. After transplantation, combinations of DAA show high efficacy and good safety profile. In the near future, extensive use of DAA should reduce the number of HCVD+ with a positive HCV RNA, limiting the risk of transmission but also the number of patients on waiting lists for a disease related to HCV.

Quasispecies dynamics in hepatitis C liver transplant recipients receiving grafts from hepatitis C virus infected donors

The allocation of liver grafts from hepatitis C virus (HCV)-positive donors in HCV-infected liver transplant (LT) recipients leads to infection with two different viral populations. In a previous study, we examined quasispecies dynamics during reinfection by clonal sequencing, which did not allow an accurate characterization of coexistence and competition events. To overcome this limitation, here we used deep-sequencing analysis of a fragment of the HCV NS5B gene in six HCV-infected LT recipients who received HCV-infected grafts. Successive expansions and contractions of quasispecies complexity were observed, evolving in all cases towards a more homogeneous population. The population that became dominant was the one displaying the highest mutant spectrum complexity. In four patients, coexistence of minority mutants, derived from the donor or the recipient, were detected. In conclusion, our study shows that, during reinfection with a different HCV strain in LT recipients, the viral population with the highest diversity always becomes dominant.

Characterization and risk of blood-borne virus transmission in organ transplantation: what are the priorities?

ABSTRACT 

Blood-borne virus transmission through organ transplantation, although rare, has been associated with severe complications in recipients. There are few data available to ascertain the risk of infection in organ transplantation for known and emerging pathogens, as most information comes from events of transmission, which are rare and not always well characterized. The balance between quality of life through organ transplantation and the risks of donor-derived infection can be improved through advances in donor screening, enhanced monitoring and a multidisciplinary approach to improving donor assessment and recipient biosurveillance. The involvement of investigators with clinical, laboratory, surveillance and policy expertise is critical to bridge research knowledge and clinical practice.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Deceased donor risk factors influencing liver transplant outcome

As the pressure for providing liver transplantation to more and more candidates increases, transplant programs have begun to consider deceased donor characteristics that were previously considered unacceptable. With this trend, attention has focused on better defining those donor factors that can impact the outcome of liver transplantation. This review examines deceased donor factors that have been associated with patient or graft survival as well as delayed graft function and other liver transplant results.

Approach to Intraoperative Consultation for Donor Liver Biopsies

Context.— As demand for organs to treat end-stage liver disease increases, donor livers once deemed only marginally suitable for donation are being considered for transplantation. Pathologists are increasingly being asked to evaluate these livers for acceptability. This article provides guidelines for frozen section evaluation of livers for transplantation.

Objective.— This article concentrates on the histopathologic features of transplant suitability with appropriate clinicopathologic correlation for the practicing pathologist. Recommendations for proper handling and sampling of tissue are discussed. Relative and absolute contraindications as well as artifacts and benign conditions are emphasized.

Data Sources.— Sources include a compilation of the authors' experiences in academic and community liver transplantation centers. In addition, relevant medical literature was reviewed, as well as Web sites specializing in organ transplantation, such as Transplant Pathology Internet Services and the Organ Procurement and Transplantation Network.

Conclusions.— Malignancy and extensive necrosis in the liver are absolute contraindications to transplantation. Evaluation of macrosteatosis, fibrosis, hepatitis, and necrosis depends on the severity of disease and correlation with the clinical situation. Donor age of greater than 60 years does not preclude transplantation. Artifacts and benign conditions need to be understood to prevent wastage of precious organs and to ensure that an appropriate organ is provided for the recipient.

Liver transplantation from anti-hepatitis C virus-positive donors: our experience

BACKGROUND

Hepatitis C (HCV) is among the most common causes of end-stage liver disease worldwide. The donor shortage leads us to consider alternative organ sources such as HCV-positive donors. The outcomes of these transplants must be evaluated thoroughly since there is universal recurrence of disease among HCV-positive liver transplant recipients.

METHODS

From January 2005 to April 2011, we performed 143 liver transplants (OLT) to treat end-stage liver disease secondary to HCV infection. Thirteen patients (9,1%) received livers from HCV-positive donors. A control group consisted of 130 HCV-positive patients who underwent OLT during the same period with organs from HCV-negative donors. Donor HCV status was assessed by 2 tests: HCV antibodies and viral load. Not only recipient and graft survivals were analyzed, but also frequency, timing and severity of hepatitis recurrence.

RESULTS

Among 143 transplants performed in HCV-positive recipients during a 6-year period from January 1, 2005, to April 30, 2011, 9.1% of patients received an organ from an anti-HCV-positive donor, 72.7% of whom showed a negative viral load. The vast majority (80%) of our patients suffered hepatitis during their follow-up, 22.4% of which were severe cases.

CONCLUSIONS

No significant difference in patient or graft survival was observed between the 2 groups. A high percentage of grafts with initial positive serology for HCV showed no viral replication. Grafts from HCV-positive donors can be considered to be a safe, effective source for liver donation.

Utilization of hepatitis C antibody-positive livers: genotype dominance is virally determined

Because of the unrelenting donor shortage, utilization of all potential liver donors is essential. However, when utilizing marginal donors it is critical to precisely characterize the risks, inform recipients of those risks, and allocate these higher risk organs to appropriate candidates. Towards this goal, we need to determine the safety and potential consequences, if any, of utilizing hepatitis C (HCV) antibody-positive donors in HCV infected recipients. To further characterize HCV antibody-positive donors, we analyzed prospectively collected serum samples from HCV antibody-positive donors transplanted into HCV RNA-positive recipients from 5/1993 to 10/2008 for HCV viral load (Roche Cobas AmpliPrep/Cobas Taqman HCV Assay) and genotype (Siemens Versant 2.0 LiPA HCV 5' UTR/Core Assay). Seventeen of 32 (53%) HCV antibody-positive donors were RNA negative. Fifteen patients received an HCV RNA-positive donor and nine donor-recipient pairs had different genotypes or subtypes for analysis. When genotype 1 competed with a non-1 genotype, it was found in 5/6 recipients. In 2/3 cases of mismatched genotype 1 subtypes, genotype 1a dominated. Kaplan-Meier analysis of patient and graft survival and fibrosis progression did not reveal differences between patients who received an HCV antibody-positive donor that was viremic or aviremic. In conclusion, approximately half of HCV antibody-positive donors were aviremic. Viral dominance in viremic donor-recipient pairs seems virally determined.

Extended donors in liver transplantation

Several criteria are used to differentiate between standard and extended allograft donors. These criteria include deceased after cardiac death, advanced donor age, steatosis, previous malignancy in the donor, hepatitis C virus-positive allografts, human T-cell lymphotropic virus-positive allografts, active infections in the donor, high-risk donors, split liver transplantations, and living donor liver transplantations. Review of the literature can lead each practitioner to incorporate extended criteria donors into their transplant program, thereby individualizing the use of these allografts, increasing the donor pool, and decreasing overall waitlist mortality.

Survival after liver transplantation using hepatitis C virus-positive donor allografts: case-controlled analysis of the UNOS database

BACKGROUND

Numerous reports have documented reduced graft and patient survival after use of hepatitis C (HCV) seropositive allografts in liver transplantation (OLT). We aimed to examine if the use of a HCV+ liver allograft affects patient and graft survivals compared to HCV- donor allografts in a case-controlled analysis of the united network for organ sharing (UNOS) database.

METHODS

We examined 63,149 liver transplants (61,905 donors HCV-; 1,244 donors HCV+) from the UNOS standard transplant analysis and research (STAR) file from 1987 to 2007. Donor and recipient demographics and outcomes were collected in which donor HCV serology was complete. A case-controlled cohort from 11 donor and recipient variables comparing donor HCV- and HCV+ allografts (n=540 in each group) was created using propensity scores with a matching algorithm. Graft and patient survival was estimated using Kaplan-Meier survival curves.

RESULTS

Significant differences were evident in the unadjusted cohort between recipients who received HCV+ and HCV- allografts, including HCV+ recipients, donor and recipient age, and model for end-stage liver disease (MELD) exception cases. Use of HCV+ allograft resulted in significantly lower graft survival (8.1 vs. 10.6 years; P=0.001) and patient survival (10.2 vs. 12.3 years; P=0.01) after OLT. In the matched cohort, HCV seropositivity had no detrimental effect on the graft (P=0.57) or patient (P=0.78) survival after OLT.

CONCLUSIONS

This is the first population-based analysis to show that after adjusting for donor and recipient characteristics there was no difference in graft or patient survival with the use of HCV+ donor liver allografts compared to HCV- donor liver allografts.

Long-term follow-up and outcome of liver transplantation from anti-hepatitis C virus-positive donors: a European multicentric case-control study

BACKGROUND

The growing prevalence of hepatitis C virus (HCV) infection in the general population has resulted in an increased frequency of potential organ donors that carry the virus. Given the significant disparity between organ supply and demand for transplantation, it becomes essential to consider whether livers from anti-HCV-positive donors may be considered suitable for transplantation.

METHODS

Based on a multicenter European database, 694 patients with HCV-related cirrhosis underwent liver transplantation and 11% of them received the graft from anti-HCV-positive donors. Of this group, we selected 63 patients (study group) and, after a 1:1 case-control approach, compared them with 63 patients that received an anti-HCV-negative donor graft (control group). Only grafts with preperfusion liver biopsy results with a fibrosis score of not more than 1 were used for transplantation.

RESULTS

Patients who received anti-HCV-positive grafts had a cumulative survival rate of 83.6% and 61.7% at 1 and 5 years, respectively, vs. 95.1% and 68.2% for the control group. In comparing overall patient and graft survival, there was no statistically significant difference between the two groups (P=0.22 and 0.11). Recurrence of hepatitis C tended to be more rapid in the group of patients who received anti-HCV-positive grafts, although it did not reach statistical significance (P=0.07).

CONCLUSIONS

We do not recommend the indiscriminate use of anti-HCV-positive donors, especially if HCV-RNA positive, as the use of this kind of graft could be linked to an advanced stage of fibrosis, the main risk factor we observed for earlier hepatitis C recurrence.

Liver allografts from hepatitis C positive donors can offer good outcomes in hepatitis C positive recipients: a US National Transplant Registry analysis

Organ donors are screened for the hepatitis C antibody (anti-HCV) and those with positive tests can be used under extended criteria donation. However, there is still a question of long-term organ viability. The aim of this study was to assess the long-term outcomes of anti-HCV positive (HCV+) liver grafts. The US Organ Procurement and Transplantation Network Scientific Registry was reviewed for the period from April 1994 to February 6, 2008 and 56,275 liver transplantations were analyzed. In total, there were 19,496 HCV+ recipients and 934 HCV+ donors. Patient and graft survival were assessed accounting for both donor and recipient anti-HCV status. Multivariable proportional hazards survival models were developed to adjust for factors known to affect post-transplant survival. With anti-HCV negative (HCV-) recipient/HCV- donor as the reference, the adjusted hazard ratio for death was similar for HCV+ recipient/HCV- donor compared with HCV+ recipient/HCV+ donor (1.176 vs. 1.165, P = 0.91). Our results suggest that HCV+ liver donors do not subject the HCV+ recipient to an increased risk for death over the HCV- donor, keeping in mind that careful donor and recipient selection is critical for the proper use of these extended criteria donors.

Human liver transplantation as a model to study hepatitis C virus pathogenesis

Hepatitis C is a leading etiology of liver cancer and a leading reason for liver transplantation. Although new therapies have improved the rates of sustained response, a large proportion of patients (approximately 50%) fail to respond to antiviral treatment, thus remaining at risk for disease progression. Although chimpanzees have been used to study hepatitis C virus biology and treatments, their cost is quite high, and their use is strictly regulated; indeed, the National Institutes of Health no longer supports the breeding of chimpanzees for study. The development of hepatitis C virus therapies has been hindered by the relative paucity of small animal models for studying hepatitis C virus pathogenesis. This review presents the strengths of human liver transplantation and highlights the advances derived from this model, including insights into viral kinetics and quasispecies, viral receptor binding and entry, and innate and adaptive immunity. Moreover, consideration is given to current and emerging antiviral therapeutic approaches based on translational research results.

[How can the number of liver transplantations be increased?]

The number of patients suitable for liver transplantation is progressively increasing due to the excellent results achieved with this procedure, giving rise to a growing imbalance in the number of candidates on the waiting list and the number of donors. This situation has prompted transplant teams to search for alternatives to increase the number of liver grafts. On the one hand, the criteria for donation have been broadened to include donors with advanced age, liver steatosis, hepatitis B and C viruses, neoplasms, and benign underlying diseases. On the other hand, new transplant techniques have been used with grafts from split livers, living donors, sequential or domino transplants and non-heart-beating donors. Other options such as xenotransplantation and hepatocyte transplants currently lack clinical applicability.

Report of the Paris consensus meeting on expanded criteria donors in liver transplantation

Because of organ shortage and a constant imbalance between available organs and candidates for liver transplantation, expanded criteria donors are needed. Experience shows that there are wide variations in the definitions, selection criteria, and use of expanded criteria donors according to different geographic areas and different centers. Overall, selection criteria for donors have tended to be relaxed in recent years. Consensus recommendations are needed. This article reports the conclusions of a consensus meeting held in Paris in March 2007 with the contribution of experts from Europe, the United States, and Asia. Definitions of expanded criteria donors with respect to donor variables (including age, liver function tests, steatosis, infections, malignancies, and heart-beating versus non-heart-beating, among others) are proposed. It is emphasized that donor quality represents a continuum of risk rather than "good or bad." A distinction is made between donor factors that generate increased risk of graft failure and factors independent of graft function, such as transmissible infectious disease or donor-derived malignancy, that may preclude a good outcome. Updated data concerning the risks associated with different donor variables in different recipient populations are given. Recommendations on how to safely expand donor selection criteria are proposed.

Hepatitis C and liver transplantation: enhancing outcomes and should patients be retransplanted

Hepatitis C (HCV)-related end-stage liver disease is the most common indication for liver transplantation. Safe expansion of the donor pool with improved rates of deceased donation and more widespread use of living and extended criteria donation are likely to decrease wait list mortality. In addition, improved antiviral treatments and a better understanding of the delicate balance between under- and over-immunosuppression in this population are needed. Finally, when recurrent advanced fibrosis occurs, the criteria for patient selection for retransplantation remain widely debated. This article reviews the literature on these topics and the work being done in each area to maximize outcomes in patients receiving transplants for HCV-related cirrhosis.

Expanding donor options: marginal, living, and split donors

One of the most important factors in the increasing number of liver transplantations performed in the United States is the growing acceptance of marginal grafts, which are defined as organs at increased risk for poor function or failure that may subject the recipient to greater risks of morbidity or mortality. Based on encouraging results, a growing number of liver transplantation centers are broadening their criteria for transplantation of marginal grafts. This article discusses the use of the extended criteria donor liver, split-liver, and living-donor liver transplantation.

Trends in post-liver transplant survival in patients with hepatitis C between 1991 and 2001 in the United States

It has been suggested that the post-liver transplantation (LT) survival rate of patients with hepatitis C virus infection (HCV) has declined in recent years. To compare the outcome of LT in patients with HCV at various time intervals between 1991 and 2001, we used United Network for Organ Sharing data to compare the post-LT survival of adult patients (age >18 years) with HCV with those without HCV. Of the 37,101 patients who underwent LT during the study period, 28,193 patients (HCV 7,459 and 20,734 non-HCV) were eligible for the study. On the basis of the time of transplantation, patients were divided into 3 groups: 1991-1993 (period 1), 1994-1997 (period 2), and 1998-2001 (period 3). The patient and graft survival rates were adjusted for other known confounding variables that influenced outcomes. The 3-year patient survival rate was lower in HCV patients compared with non-HCV recipients (78.5% vs. 81.4%, hazard ratio 1.14, 95% confidence interval 1.05-1.23, P = 0.001). The graft (72.8%, 71.0%, and 69.8%) and patient (77.4%, 79.6%, and 78.5%) survival of HCV patients remained unchanged during study periods 1-3, respectively. However, the graft and patient survival rates of non-HCV recipients improved markedly during study periods 2 and 3 compared with period 1. The graft and patient survival has remained unchanged between 1991 and 2001 in HCV recipients, but during the same period, there was a great improvement in survival among non-HCV recipients.

Should antihepatitis B virus core positive or antihepatitis C virus core positive subjects be accepted as organ donors for liver transplantation?

Since the introduction of liver transplantation as a routine surgical procedure for the treatment of end-stage liver disease, there has been an increasing gap between the number of available grafts and the number of patients on the waiting list. This has led transplant centers to expand the donor pool by different means. One of them has been the introduction of living donor liver transplantation. Other strategies include using less than optimal allografts from deceased donors, the so-called marginal donors, which include the use of grafts from older subjects, livers with moderate amounts of steatosis, or from donors with markers of past or current infection with hepatitis viruses who have absent or minimal liver biochemical or histologic injury. In this review, we will focus on the current use of allografts from donors with antihepatitis B core antibody and/or antibodies against hepatitis C virus in cadaveric and living donor liver transplantation.

Use of extended criteria livers decreases wait time for liver transplantation without adversely impacting posttransplant survival

INTRODUCTION

The use of extended criteria donors (ECDs) could minimize shortage of suitable donor livers for transplantation. In 3 years, the aggressive use of ECD livers has reduced the wait list at our center from 257 to 30 patients with a median wait time of 18 days without using living donors. This study compares the graft/patient survival from standard (SD) and ECD for our transplant population between 2001 and 2005.

METHODS

Records of all adult liver transplant recipients over 4 years were reviewed (n = 571). ECD criteria included: age >59 years, BMI >34.9, maximum AST/ALT >500, maximum bilirubin >2.0, peak serum sodium >170, HBV/HCV/HTLV reactive, donation after cardiac death, cold ischemia time >12 hours, ICU stay >5 days, 3 or more pressors simultaneously, extensive alcohol abuse, cancer history (nonskin), active meningitis/bacteremia, or significant donor liver trauma. Outcomes included graft and patient survival at 90 days, 1 year, and 2 years.

RESULTS

Sixty-eight percent of recipients (n = 388) received ECD livers. Primary factors accounting for ECD-liver status included: elevated liver function tests (20%), hypernatremia (12.6%), and extensive alcohol abuse (11.4%). Graft survival was (SD, ECD): 90-day 91%, 88%; 1-year 84%, 80%; 2-year 78%, 77%; patient survival was: 90-day 93%, 90%; 1-year 87%, 82%; 2-year 83%, 79%. Kaplan-Meier survival analysis failed to demonstrate an overall difference in graft or patient survival at any time point. Only donor age >60 years was associated with decreased graft and patient survival.

CONCLUSIONS

Liver grafts from ECD can be used to dramatically reduce wait list time with outcomes comparable to those for SD without resorting to living donor liver transplantation.

Impact of donor age on survival and fibrosis progression in patients with hepatitis C undergoing liver transplantation using HCV+ allografts

Studies have suggested that the use of hepatitis C virus (HCV)-positive (HCV+) donor allografts has no impact on survival. However, no studies have examined the effect that HCV+ donor histology has upon recipient and graft survival. We evaluated the clinical outcome and impact of histological features in HCV patients transplanted using HCV+ livers. We reviewed all patients transplanted for HCV at our institution from 1988 to 2004; 39 received HCV+ allografts and 580 received HCV-negative (HCV-) allografts. Survival curves compared graft and patient survival. Each HCV+ allograft was stringently matched to a control of HCV- graft recipients. No significant difference in survival was noted between recipients of HCV+ livers and controls. Patients receiving HCV+ allografts from older donors (age > or =50 yr) had higher rates of graft failure (hazard ratio, 2.74) and death rates (hazard ratio, 2.63) compared to HCV- allograft recipients receiving similarly-aged older donor livers. Matched case-control analysis revealed that recipients of HCV+ allografts had more severe fibrosis post-liver transplantation than recipients of HCV- livers (P = 0.008). More advanced fibrosis was observed in HCV+ grafts from older donors compared to HCV+ grafts from younger donors (P = 0.012). In conclusion, recipients of HCV+ grafts from older donors have higher rates of death and graft failure, and develop more extensive fibrosis than HCV- graft recipients from older donors. Recipients of HCV+ grafts, regardless of donor age, develop more advanced liver fibrosis than recipients of HCV- grafts.

Treating hepatitis C infection in liver transplant recipients

Chronic infection with hepatitis C virus (HCV) is a growing problem worldwide, with up to 300 million individuals infected, and those with chronic infection are at risk for cirrhosis and hepatocellular carcinoma. HCV infection is the most common indication for liver transplantation in the United States and Europe. Unfortunately, although transplantation is effective for treating decompensated cirrhosis and limited hepatocellular carcinoma associated with hepatitis C, HCV reinfection is virtually the rule among transplant recipients. Reinfection of the graft is associated with more rapidly progressive disease, with a median time to cirrhosis of 8 to 10 yr. Unfortunately, treatment of chronic HCV in liver transplant recipients is suboptimal. Combination therapy with interferon (pegylated and nonpegylated forms) plus ribavirin appears to provide maximum benefits. Drug therapy is usually administered for recurrent disease. No prophylactic therapy is available. Preemptive regimens offer no distinctive advantages over treatments begun for recurrent disease. Overall, treatment is poorly tolerated, with frequent need for dose reductions, especially from cytopenias, and drug discontinuations in up to 50% of patients. Optimizing drug doses is important in maximizing sustained virological response rates. Future therapies may include ribavirin alternatives with lower rates of anemia, alternative interferons with lower rates of cytopenias, and new antiviral drugs that can be used alone or in combination with either interferon or ribavirin to enhance sustained virological response rates and improve tolerability. Liver Transpl 12:1192-1204, 2006. (c) 2006 AASLD.

Viral evolution of hepatitis C in injection drug users

Injection drug users represent the largest cohort of patients with established hepatitis C virus (HCV) infection as well as the group that is at highest risk for new infections. Most published studies have focused on the clinical consequences of established HCV infection and have not examined the consequences of new infection. The aim of the current study was to measure the virological consequences of HCV in patients with ongoing injection drug use that might pose a risk for new and/or for superinfection with additional strains of HCV. We examined the following groups: (a) those with resolved HCV infection with ongoing injection drug use, (b) those with chronic infection who continued to inject and (c) those with chronic infection who no longer injected. Our study demonstrated a spectrum of responses. The majority of patients appeared to be 'protected' from new infection. None of six patients with resolved infection had detectable HCV RNA by quantitative or qualitative PCR when followed for 1 year. Similarly, despite ongoing injection drug use, no patient with persistent infection had a 'switch' in HCV genotype indicative of possible superinfection. Virological analysis of HCV quasispecies to detect possible infection with new variants of HCV in patients with apparently 'stable' infection, indicated divergence of virus over time, divergence that was unrelated to injection drug behaviour. Thus, patients with ongoing or prior HCV infection appear to develop immunity that protects against further infection with HCV despite repeated exposure.