Mild donor liver steatosis has no impact on hepatitis C virus fibrosis progression following liver transplantation

Impact of Graft Steatosis on Postoperative Complications after Liver Transplantation

Background  Steatotic grafts are more susceptible to ischemia-reperfusion injury than are normal grafts. Therefore, using steatotic grafts for liver transplantation (LT) is associated with high primary dysfunction and decreased survival rates. The aim of this study is to evaluate the impact of graft steatosis on post LT outcomes. Methods  A retrospective cohort analysis of 271 LT recipients from 2005 to 2016 was performed and patients were classified based on two types of steatosis, macrosteatosis (MaS), and microsteatosis (MiS). Each category was subdivided into three groups according to the degree of steatosis: no (< 5%), mild (≥5 to < 30%), and moderate (≥30 to ≤60%). The primary hospital stays and 6-month postoperative complications were analyzed by the Clavien-Dindo classification system. Additionally, patient and graft survivals were studied. Results  Significant differences were observed in grade III MaS ( p -value = 0.019) and grade V MiS ( p -value = 0.020). A high trend of early graft dysfunction was found in the moderate MaS and MiS groups; however, they were not statistically significant ( p -value = 0.199 and 0.282, respectively). Interestingly, the acute cellular rejection (ACR) rate was found to be inversely proportional to the degree of steatosis in both categories but it did not reach a significant level ( p -value = 0.161 and 0.111, respectively). Conclusion  Excellent post LT long-term outcomes using grafts with mild and moderate steatosis were determined. Further studies are needed to evaluate the newly proposed relationship between ACR and steatosis.

Extended-criteria donors in liver transplantation Part II: reviewing the impact of extended-criteria donors on the complications and outcomes of liver transplantation

Extended-criteria donors (ECDs) have an impact on early allograft dysfunction (EAD), biliary complications, relapse of hepatitis C virus (HCV), and survivals. Early allograft dysfunction was frequently seen in grafts with moderate and severe steatosis. Donors after cardiac death (DCD) have been associated with higher rates of graft failure and biliary complications compared to donors after brain death. Extended warm ischemia, reperfusion injury and endothelial activation trigger a cascade, leading to microvascular thrombosis, resulting in biliary necrosis, cholangitis, and graft failure. The risk of HCV recurrence increased by donor age, and associated with using moderately and severely steatotic grafts. With the administration of protease inhibitors sustained virological response was achieved in majority of the patients. Donor risk index and EC donor scores (DS) are reported to be useful, to assess the outcome. The 1-year survival rates were 87% and 40% respectively, for donors with a DS of 0 and 3. Graft survival was excellent up to a DS of 2, however a DS >2 should be avoided in higher-risk recipients. The 1, 3 and 5-year survival of DCD recipients was comparable to optimal donors. However ECDs had minor survival means of 85%, 78.6%, and 72.3%. The graft survival of split liver transplantation (SLT) was comparable to that of whole liver orthotopic liver transplantation. SLT was not regarded as an ECD factor in the MELD era any more. Full-right-full-left split liver transplantation has a significant advantage to extend the high quality donor pool. Hypothermic oxygenated machine perfusion can be applied clinically in DCD liver grafts. Feasibility and safety were confirmed. Reperfusion injury was also rare in machine perfused DCD livers.

Extended criteria donors in liver transplantation Part I: reviewing the impact of determining factors

The definition and factors of extended criteria donors have already been set; however, details of the various opinions still differ in many respects. In this review, we summarize the impact of these factors and their clinical relevance. Elderly livers must not be allocated for hepatitis C virus (HCV) positives, or patients with acute liver failure. In cases of markedly increased serum transaminases, donor hemodynamics is an essential consideration. A prolonged hypotension of the donor does not always lead to an increase in post-transplantation graft loss if post-OLT care is proper. Hypernatremia of less than 160 mEq/L is not an absolute contraindication to accept a liver graft per se. The presence of steatosis is an independent and determinant risk factor for the outcome. The gold standard of the diagnosis is the biopsy. This is recommended in all doubtful cases. The use of HCV+ grafts for HCV+ recipients is comparable in outcome. The leading risk factor for HCV recurrence is the actual RNA positivity of the donor. The presence of a proper anti-HBs level seems to protect from de novo HBV infection. A favourable outcome can be expected if a donation after cardiac death liver is transplanted in a favourable condition, meaning, a warm ischemia time < 30 minutes, cold ischemia time < 8-10 hours, and donor age 50-60 years. The pathway of organ quality assessment is to obtain the most relevant information (e.g. biopsy), consider the co-existing donor risk factors and the reserve capacity of the recipient, and avoid further technical issues.

Challenges of recurrent hepatitis C in the liver transplant patient

Cirrhosis secondary to hepatitis C virus (HCV) is a very common indication for liver transplant. Unfortunately recurrence of HCV is almost universal in patients who are viremic at the time of transplant. The progression of fibrosis has been shown to be more rapid in the post-transplant patients than in the transplant naïve, hence treatment of recurrent HCV needs to be considered for all patients with documented recurrent HCV. Management of recurrent HCV is a challenging situation both for patients and physicians due to multiple reasons as discussed in this review. The standard HCV treatment with pegylated interferon and Ribavarin can be considered in these patients but it leads to a lower rate of sustained virologic clearance than in the non-transplanted population. Some of the main challenges associated with treating recurrent HCV in post-transplant patients include the presence of cytopenias; need to monitor drug-drug interactions and the increased incidence of renal compromise. In spite of these obstacles all patients with recurrent HCV should be considered for treatment since it is associated with improvement in survival and a delay in fibrosis progression. With the arrival of direct acting antiviral drugs there is renewed hope for better outcomes in the treatment of post-transplant HCV recurrence. This review evaluates current literature on this topic and identifies challenges associated with the management of post-transplant HCV recurrence.

Strategies to reduce hepatitis C virus recurrence after liver transplantation

Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunately, HCV re-infects the liver graft almost invariably following reperfusion, with an accelerated history of recurrence, leading to 10%-30% of patients progressing to cirrhosis within 5 years of transplantation. In this sense, some groups have even advocated for not re-transplanting this patients, as lower patient and graft outcomes have been reported. However, the management of HCV recurrence is being optimized and several strategies to reduce post-transplant recurrence could improve outcomes, decrease the rate of re-transplantation and optimize the use of available grafts. Three moments may be the focus of potential actions in order to decrease the impact of viral recurrence: the pre-transplant moment, the transplant environment and the post-transplant management. In the pre-transplant setting, it is not well established if reducing the pre transplant viral load affects the risk for HCV progression after transplant. Obviously, antiviral treatment can render the patient HCV RNA negative post transplant but the long-term benefit has not yet been fully established to justify the cost and clinical risk. In the transplant moment, factors as donor age, cold ischemia time, graft steatosis and ischemia/reperfusion injury may lead to a higher and more aggressive viral recurrence. After the transplant, discussion about immunosuppression and the moment to start the treatment (prophylactic, pre-emptive or once-confirmed) together with new antiviral drugs are of interest. This review aims to help clinicians have a global overview of post-transplant HCV recurrence and strategies to reduce its impact on our patients.

Prevention of hepatitis C recurrence after liver transplantation: An update

Hepatitis C related liver failure and hepatocarcinoma are the most common indications for liver transplantation in Western countries. Recurrent hepatitis C infection of the allograft is universal and immediate following liver transplantation, being associated with accelerated progression to cirrhosis, graft loss and death. Graft and patient survival is reduced in liver transplant recipients with recurrent Hepatitis C virus (HCV) infection compared to HCV-negative recipients. Many variables may impact on recurrent HCV liver disease. Overall, excess immunosuppression is believed to be a key factor; however, no immunosuppressive regimen has been identified to be more beneficial or less harmful. Donor age limitations, exclusion of moderately to severely steatotic livers and minimization of ischemic times could be a potential strategy to minimize the severity of HCV disease in transplanted subjects. After transplantation, antiviral therapy based on pegylated IFN alpha with or without ribavirin is associated with far less results than that reported for immunocompetent HCV-infected patients. New findings in the field of immunotherapy and genomic medicine applied to this context are promising.

HCV in liver transplantation

HCV-related cirrhosis represents the leading indication for liver transplantation in the Western countries. HCV reinfection after liver transplantation occurs in virtually all patients transplanted for HCV-related liver disease Histological evidence of chronic HCV infection develops in 50 to 90 % of patients by 12 months after liver transplantation, and cirrhosis occurs in about 20 % of patients within 5 years after transplant. Several studies have evaluated host, viral, and transplant-related factors that might be associated with the severity of HCV recurrence. Among host factors, immunosuppression is one of the major factors that accounts for accelerated HCV recurrence and it has been an area of extensive research and controversy. Donor age, steatosis, and immunogenetic factors are also relevant in determining the outcome in patients transplanted for HCV-related cirrhosis. A major step to prevent complications of HCV recurrence related to the rapid fibrosis is the posttransplant antiviral treatment. Two strategies have been tried: pre-emptive or other strategies as soon as possible after liver transplantation or elective therapy once there is histological evidence of recurrent hepatitis C. Retransplantation due to graft failure from recurrent hepatitis C is rarely an option in the era of organ shortage as it is associated with poor outcome, but many case needs to be considered early in the evolution of disease. New antivirals may change the outcome dramatically of patients transplanted for HCV cirrhosis.

Safety and feasibility of diet-treated donors with steatotic livers at the initial consultation for living-donor liver transplantation

BACKGROUND

The purpose of this study was to evaluate both safety of diet-treated donors and the feasibility of their use for living-donor liver transplantation (LDLT).

METHODS

A total of 128 living donors were enrolled in this study between April 2003 and March 2010. Of them, 41 were diagnosed with hepatic steatosis at the initial consultation. Donor selection was based on the findings of liver biopsy accompanied with normalization of liver function tests after diet treatment consisting of an 800 to 1400 kcal/day diet and a 100 to 400 kcal/day exercise without drug treatment, targeting body mass index of 22 kg/m².

RESULTS

Body mass index of diet-treated donors was significantly reduced with diet from 23.3 ± 0.6 to 21.9 ± 0.4 kg/m² (P<0.0001). Liver function tests associated with fatty liver, including alanine aminotransferase, gamma-glutamyl transpeptidase, and total cholesterol levels, also improved with diet (P=0.0128, 0.0016, and 0.0004, respectively). The liver biopsy results of most of these donors showed stage 0/1 fibrosis and minimal/mild steatosis after the diet therapy. Surgical outcomes, including postoperative liver function tests, perioperative complications, and liver regeneration rates, did not significantly differ between nondiet-treated and diet-treated donors. Surgical outcomes and the overall survival did not significantly differ between recipients of grafts from nondiet-treated and diet-treated donors.

CONCLUSION

The use of diet-treated donors for living-donor liver transplantation is feasible with respect to donor safety and the outcome of the recipient when strict selection criteria are used.

Impact of donor histology on survival following liver transplantation for chronic hepatitis C virus infection: a Scandinavian single-center experience

OBJECTIVE

Survival following liver transplantation for hepatitis C virus (HCV) infection is affected by several factors. The aims of this single-center study were to evaluate survival from 1992 to 2006 in HCV-infected liver transplant recipients and to identify factors influencing patient and graft survival, with particular focus on donor liver histopathology.

MATERIAL AND METHODS

Survival among 84 patients transplanted for HCV-related liver disease at the Sahlgrenska University Hospital during the above period was evaluated. Median follow-up time was 57 months (range 28-87). A perioperative liver biopsy from the donor liver graft was available in 68 cases. Biopsies were assessed for fibrosis, necroinflammatory activity, and degree of steatosis. Patient and graft survival according to relevant factors including donor histopathology were analyzed by Kaplan-Meier analysis.

RESULTS

We found an association between donor liver fibrosis and patient survival (p = 0.016) as well as between graft survival and portal inflammation in the donor liver (p = 0.026). Both these associations remained significant in multivariate analysis (p = 0.007 and 0.017 respectively). Moreover, recipient age over 60 was found predictive of patient survival and repeated steroid boluses or steroid-resistant rejection of graft survival. Donor age was high throughout the study period.

CONCLUSION

Histopathological features, especially portal inflammation and stage of fibrosis, in the donor liver may deleteriously affect graft and patient survival following HCV-related liver transplantation. Thus, pretransplant evaluation of donor histopathology may be of value in the selection of donors for transplantation of HCV-positive individuals, especially among donors older than 60 years.

New and Evolving Management Paradigms for Hepatitis C after Liver Transplantation

Hepatitis-C induced liver failure is the leading indication for liver transplantation in the United States, and the burden of hepatitis C virus (HCV)-induced liver disease is not expected to peak for at least another decade. 2011 will usher in a new era of directly acting antiviral therapies and personalized medicine that will assist patients and clinicians in choosing the best drug regimen. Specific markers to predict sustained virologic response (SVR) in the posttransplant setting are under development, and the role of graft genetic markers like interleukin-28B and interferon-γ inducible protein-10 have yet to be fully defined. Lessons and experiences from treating the pretransplant population will be applied to patients with recurrent posttransplant HCV while studies specific to this population proceed. New paradigms for HCV treatment give promise to reducing the pretransplant burden of disease and improving SVR rates in the posttransplant population.

Hepatic steatosis is not always a contraindication for cadaveric liver transplantation

BACKGROUND

Macrovesicular steatosis is assumed to be an important risk factor for early allograft dysfunction (EAD) after orthotopic liver transplantation (OLT).

AIM

To evaluate the impact of steatosis in combination with other risk factors on the outcome of OLT.

METHODS

The degree of steatosis was analysed in 165 consecutive OLTs and was classified by histological examination as non (M0), mild (<30%, M1), moderate (30-60%, M2) or severe steatosis (>60%, M3). Recipients were analysed for EAD.

RESULTS

EAD was observed in 28% of patients with M0, 26% with M1, 53% with M2 and 73% with M3 (P < 0.001). Patients with EAD had a significantly shorter graft survival after liver transplantation (P = 0.005) but did not correlate with survival. In multivariate regression analysis, the grade of steatosis, donating after cardiocirculatory death (DCD) grafts and duration of cold ischaemia time were significantly associated with EAD (P < 0.001, P = 0.01 and P = 0.001, respectively).

CONCLUSION

Livers with severe (M3) steatosis from DCD donors, combined with a prolonged CIT have a high risk for developing EAD which is correlated with shorter graft survival. Therefore M3 livers should only be considered for OLT in selected recipients without the presence of additional risk factors.

Steatosis and insulin resistance in hepatitis C: A way out for the virus?

The hepatitis C virus (HCV) induces lipid accumulation in vitro and in vivo. The pathogenesis of steatosis is due to both viral and host factors. Viral steatosis is mostly reported in patients with genotype 3a, whereas metabolic steatosis is often associated with genotype 1 and metabolic syndrome. Several molecular mechanisms responsible for steatosis have been associated with the HCV core protein, which is able to induce gene expression and activity of sterol regulatory element binding protein 1 (SREBP1) and peroxisome proliferator-activated receptor γ (PPARγ), increasing the transcription of genes involved in hepatic fatty acid synthesis. Steatosis has been also implicated in viral replication. In infected cells, HCV core protein is targeted to lipid droplets which serve as intracellular storage organelles. These studies have shown that lipid droplets are essential for virus assembly. Thus, HCV promotes steatosis as an efficient mechanism for stable viral replication. Chronic HCV infection can also induce insulin resistance. In patients with HCV, insulin resistance is more strongly associated with viral load than visceral obesity. HCV seems to lead to insulin resistance through interference of intracellular insulin signalling by HCV proteins, mainly, the serine phosphorylation of insulin receptor-1 (IRS-1) and impairment of the downstream Akt signalling pathway. The HCV core protein interferes with in vitro insulin signalling by genotype-specific mechanisms, where the role of suppressor of cytokine signal 7 (SOCS-7) in genotype 3a and mammalian target of rapamycin (mTOR) in genotype 1 in IRS-1 downregulation play key roles. Steatosis and insulin resistance have been associated with fibrosis progression and a reduced rate of sustained response to peginterferon plus ribavirin.

Donor livers with steatosis are safe to use in hepatitis C virus-positive recipients

Whether donor graft steatosis affects liver function and influences survival after liver transplantation is still open to debate. The aim of this study was to assess the impact of donor graft steatosis on long-term liver histology after liver transplantation. One hundred sixteen consecutive liver transplants were performed in 56 hepatitis C virus-positive (HCV+) patients and 60 HCV- patients who had protocol liver biopsies at 6, 12, 24, and 36 months after liver transplantation. Liver biopsies were obtained from all grafts. No steatosis was seen in 50.9% of the biopsies taken at the back table before implantation, whereas steatosis was mild in 39.6% of the samples and moderate/severe in 9.5% of the samples. In the 56 HCV+ recipients, fibrosis stage 3 was seen in 22.2% and stage 4 was seen in 2.2% of 45 biopsies at 36 months after liver transplantation. There was no correlation between donor graft steatosis and fibrosis after liver transplantation, regardless of the etiology of liver disease. No difference in 36-month survival after liver transplantation was seen, regardless of whether the etiology of the patient's liver disease was HCV-related or non-HCV-related (80.3% versus 75%; P = 0.4) and whether the steatosis in the graft was reportedly absent, mild, or moderate/severe (79.7% versus 73.9% versus 81.1%; P = 0.7). In conclusion, nearly one-quarter of HCV+ recipients have precirrhosis/cirrhosis 3 years after liver transplantation. Steatotic grafts do not seem to exacerbate the progression of fibrosis in HCV+ recipients, nor do they seem to negatively affect 3-year patient survival.

Killer cell immunoglobulin-like receptor genotype and killer cell immunoglobulin-like receptor-human leukocyte antigen C ligand compatibility affect the severity of hepatitis C virus recurrence after liver transplantation

In 20% to 30% of infected individuals, hepatitis C virus (HCV) can cause cirrhosis and hepatocellular carcinoma, for which liver transplantation is the best treatment available. HCV re-infection is universal, and hepatitis disease recurrence occurs in most cases with a 30% probability of progression to graft cirrhosis at 5 years post-transplant. The immunological response to HCV involves natural killer (NK) cells and killer cell immunoglobulin-like receptors (KIRs), which specifically recognize human leukocyte antigen (HLA) class I antigens present on target cells. The effector functions of NK cells are influenced by inhibitory KIR interaction with self-HLA class I ligands, with HLA-C being the most predominant. This study examines the roles of KIR genotypes and their HLA ligands in both HCV disease recurrence and its progression. A total of 151 patients were included in the cohort, and their clinical details were recorded. Liver biopsies were used to define the absence/presence of recurrent hepatitis, the degree of fibrosis, and the progression to cirrhosis over a 10-year period. Mismatching of KIR-HLA-C ligands between donor-recipient pairs was associated with the recurrence of hepatitis (P = 0.008). The presence of KIR2DL3 in the recipient correlated with progression to liver fibrosis (P = 0.04). The mismatching of HLA-KIR ligands favored the progression of the recurrent hepatitis to fibrosis only in the presence of KIR2DL3 (P = 0.04). These preliminary results indicate that the KIR genotype and KIR-HLA-C ligand compatibility play roles in the recurrence and progression of hepatitis C disease in liver transplant recipients.

A re-evaluation of the risk factors for the recurrence of primary sclerosing cholangitis in liver allografts

Previously, we have found that the absence of the colon after liver transplantation (LT) protects the patient from recurrent primary sclerosing cholangitis (rPSC). As our previous observation has not been confirmed in other series, we have reviewed our cohort of patients grafted for primary sclerosing cholangitis (PSC) with greater numbers and longer follow-up to reassess the rate, consequences, and risk factors for rPSC. We collected data on patients who underwent LT for PSC between January 1986 and April 2006. Data were collected for cytomegalovirus status, inflammatory bowel disease status, time of colectomy, type of colectomy, donor-recipient gender mismatch, recipient sex, extended donor criteria (EDC), and donor risk index. Accepted criteria were used to diagnose rPSC. Of a total of 230 consecutive adult patients, 61 (27%) underwent colectomy pre-/peri-LT, and 54 (23.5%) developed rPSC at a median of 4.6 (range, 0.5-12.9) years post-LT. A total of 263 deceased donor grafts were used, and 73 were EDC grafts. A diagnosis of rPSC was made in 61 of the 263 grafts (23%). The recurrence-free patient survival was significantly better (P < 0.05) in patients who underwent pre-/peri-LT colectomy and in those with non-EDC grafts. In conclusion, in this larger cohort of 230 patients and with longer follow-up of 82.5 (range, 0.0-238.6) months [in comparison with the previous report of 152 recipients with a follow-up of 52.8 (range, 1-146) months], we have shown that colectomy remains a significant risk factor for rPSC and that colectomy before and during initial LT for PSC confers a protective effect against rPSC in subsequent graft(s). Moreover, we have shown that EDC grafts are also a significant risk factor for rPSC.

Impact of donor graft steatosis on overall outcome and viral recurrence after liver transplantation for hepatitis C virus cirrhosis

The aim of this study was to determine the influence of donor graft steatosis on overall outcome, viral recurrence, and fibrosis progression in orthotopic liver transplantation (OLT) for hepatitis C virus (HCV) cirrhosis. One hundred twenty patients who underwent OLT for HCV cirrhosis between 1995 and 2005 were included in the study. Donor steatosis was categorized as absent (0%-10%; n = 40), mild (10%-30%; n = 32), moderate (30%-60%; n = 29), or severe (>60%; n = 19). A Cox multivariate analysis for marginal donor variables and a Model for End-Stage Liver Disease index were performed. Fibrosis evolution was analyzed in liver biopsies (fibrosis < 2 or > or =2) 3, 6, and 12 months post-OLT and in the late post-OLT period. Fifty-six grafts were lost (46%). The survival of the grafts was inversely proportional to donor liver steatosis: 82%, 72%, and 72% at 1, 2, and 3 years post-OLT in the absence of steatosis; 73%, 63%, and 58% with mild steatosis; 74%, 62%, and 43% with moderate steatosis; and 62%, 49%, and 42% with severe steatosis (P = 0.012). HCV recurrence was earlier and more frequent in recipients with steatosis > 30% (46% versus 32% at 3 months, P = 0.017; 58% versus 43% at 6 months, P = 0.020; 70% versus 56% at 12 months, P = 0.058; and 95% versus 69% at 3 years post-OLT, P = 0.0001). Graft survival was lower in alcoholic liver disease recipients versus HCV recipients when steatosis was >30% at 3, 6, and 12 months post-OLT (P = 0.042) but not when steatosis was <30% (P = 0.53). A higher fibrosis score was obtained 3 months post-OLT (P = 0.033), 6 months post-OLT (P = 0.306), 12 months post-OLT (P = 0.035), and in the late post-OLT period (P = 0.009). In conclusion, donor graft steatosis influences the outcome of OLT for HCV cirrhosis. HCV recurrence is more frequent and earlier in recipients of moderately and severely steatotic livers. Fibrosis evolution is higher when graft steatosis is >30%. OLT with >30% steatotic donor livers should be precluded in HCV recipients.