Insulin resistance, serum adipokines and risk of fibrosis progression in patients transplanted for hepatitis C

Pancreatic steatosis is an independent risk factor for post-transplant diabetes mellitus in kidney transplant patients

BACKGROUND AND AIM

Post-transplant diabetes mellitus (PTDM) is associated with an increased risk of post-transplant cardiovascular diseases, and several risk factors of PTDM have been shown in the literature. Yet, the relationship between hepatic and pancreatic steatosis with post-transplant diabetes mellitus remains vague. We aimed to evaluate pancreatic steatosis, a novel component of metabolic syndrome, and hepatic steatosis association with post-transplant diabetes mellitus in a single-center retrospective cohort study conducted on kidney transplant recipients.

METHOD

We have performed a single-center retrospective cohort study involving all kidney transplant recipients. We have utilized pretransplant Fibrosis-4, nonalcoholic fatty liver disease fibrosis score, and abdominal computed tomography for the assessment of visceral steatosis status.

RESULTS

We have included 373 kidney transplant recipients with a mean follow-up period of 32 months in our final analysis. Post-transplant diabetes mellitus risk is associated with older age (p < .001), higher body-mass index (p < .001), nonalcoholic fatty liver disease-fibrosis score (p = .002), hepatic (p < .001) or pancreatic (p < .001) steatosis on imaging and higher pre-transplant serum triglyceride (p = .003) and glucose levels (p = .001) after multivariate analysis.

CONCLUSION

Our study illustrates that recipients' pancreatic steatosis is an independent predictive factor for post-transplant diabetes mellitus including in kidney transplant patients.

A Comprehensive Review of Liver Allograft Fibrosis and Steatosis: From Cause to Diagnosis

Despite advances in posttransplant care, long-term outcomes for liver transplant recipients remain unchanged. Approximately 25% of recipients will advance to graft cirrhosis and require retransplantation. Graft fibrosis progresses in the context of de novo or recurrent disease. Recurrent hepatitis C virus infection was previously the most important cause of graft failure but is now curable in the majority of patients. However, with an increasing prevalence of obesity and diabetes and nonalcoholic fatty liver disease as the most rapidly increasing indication for liver transplantation, metabolic dysfunction-associated liver injury is anticipated to become an important cause of graft fibrosis alongside alloimmune hepatitis and alcoholic liver disease. To better understand the landscape of the graft fibrosis literature, we summarize the associated epidemiology, cause, potential mechanisms, diagnosis, and complications. We additionally highlight the need for better noninvasive methods to ameliorate the management of graft fibrosis. Some examples include leveraging the microbiome, genetic, and machine learning methods to address these limitations. Overall, graft fibrosis is routinely seen by transplant clinicians, but it requires a better understanding of its underlying biology and contributors that can help inform diagnostic and therapeutic practices.

Hepatitis C Virus, Insulin Resistance, and Diabetes: A Review

Hepatitis C virus (HCV) infection and diabetes mellitus (DM) are two chronic diseases that are a cause of significant health and economic burdens worldwide. HCV is associated with the development of insulin resistance (IR) and diabetes mellitus (DM). The mechanisms through which HCV induces IR and DM include direct viral effects, pro-inflammatory cytokines and other immune-mediated processes. Type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) are both chronic diseases that involve impaired glucose homeostasis, albeit through different mechanisms. T1DM is an autoimmune disease that leads to the destruction of pancreatic beta cells resulting in insulin deficiency. In T2DM, a combination of peripheral insulin resistance and irregular production of insulin eventually lead to beta cell destruction and insulin insufficiency. Both type 1 and type 2 DM etiologies involve a combination of genetic and environmental factors. The data on HCV and T1DM association is limited, unlike T2DM, where a large body of evidence linking HCV to T2DM is available. Here, we intend to outline the current state of knowledge on HCV, IR, and DM. This article is protected by copyright. All rights reserved.

Cirrhosis and insulin resistance: current knowledge, pathophysiological mechanisms, complications and potential treatments

End-stage chronic liver diseases are often associated with insulin resistance (IR) and diabetes mellitus (DM). Indeed, to quantify insulin sensitivity the euglycemic clamp technique was utilized, allowing the following to be stated: in small groups of patients, an IR in almost all cirrhotic patients can be observed, compared with a control group. Additionally, it has been demonstrated that IR in cirrhosis is linked to a decreased peripheral (muscle) glucose uptake rather than an increased liver glucose production. The homoeostasis model of IR (HOMA-IR) technique, devised only later, was then exploited to assess this same phenomenon in a larger sample population. The research established that even in patients with preserved liver function, cirrhosis is associated with significant alterations in glucose homoeostasis levels. The purpose of the present paper is to present the current research around the affiliation of cirrhosis and IR, discuss potential mechanisms explaining the association between cirrhosis and IR (i.e. endocrine perturbation, liver inflammation, altered muscle mass and composition, altered gut microbiota and permeability), complications that can arise as well as treatment options, through a critical review of the literature surrounding this subject. This research will also be investigating the beneficial impact, if there is any, of identifying and curing IR in patients with cirrhosis.

Metabolic Disorders After Liver Transplantation

Early after surgery, liver transplant (LT) recipients often develop weight gain due to an increase of caloric intake and fat mass (without recovery of muscle frame). This modification of body composition together with a negative metabolic impact of immunosuppressive drugs leads to a high prevalence of all the main metabolic disorders. Indeed, as expected, transplanted patients show a higher cardiovascular risk in comparison with general population. Notably, seeing the increase of mean age of transplanted population, metabolic disorders represent the true challenge for the transplant community. Considering the lack of evidences or clear indications about prevention, early diagnosis and treatment of metabolic disorders after LT, it would be mandatory to develop targeted further studies on this matter.

Medical care of liver transplant patients

INTRODUCTION

Liver transplantation is a life-changing event for patients and survival following transplantation has improved significantly since the first transplantation in 1967. Following liver transplantation, patients face a unique set of healthcare management decisions including transplantation-specific complications, recurrence of primary liver disease, as well as metabolic and malignancy concerns related to immunosuppression. As more patients with liver disease receive transplantation and live longer, understanding and managing these patients will require not only transplant specialist but also local subspecialist and primary care physicians.

AREAS COVERED

This review covers common issues related to the management of patients following liver transplantation including immunosuppression, liver allograft dysfunction, metabolic complications, as well as routine health maintenance such as immunizations and cancer screening.

EXPERT OPINION

Optimizing medical care for patients following liver transplant will benefit from ensuring all providers, not just transplant specialist, have a basic understanding of the common issues encountered in the post-transplant patient. This review provides an overview of common healthcare concerns and management options for patients following liver transplantation.

Hepatic steatosis and liver fat contents in liver transplant recipients are associated with serum adipokines and insulin resistance

Our data about pathogenesis of hepatic steatosis after liver transplantation is scarce. This study aimed to investigate the association between serum adipokines and insulin resistance with hepatic steatosis in liver transplant recipients. We investigated the association between insulin resistance, serum adiponectin, insulin, and leptin with hepatic steatosis in a cohort of liver transplant recipients. Homeostatic model assessment of insulin resistance 2 (HOMA 2-IR) was used for estimation of insulin resistance. Hepatic steatosis was determined using ultrasound and controlled attenuation parameter (CAP). A total of 178 patients were included. 79 patients (44.4%) had hepatic steatosis. Serum adiponectin (OR: 0.912; 95% CI 0.869–0.957; P < 0.001), serum leptin (OR: 1.060; 95% CI 1.017–1.102; P = 0.005), HOMA2-IR (OR: 1.671; 95% CI 1.049–2.662; P = 0.031), and post-transplant diabetes mellitus (PTDM) (OR: 5.988; 95% CI 1.680–21.276; P = 0.006) were independently associated with hepatic steatosis after liver transplantation. CAP values were negatively correlated with serum adiponectin (P = 0.011) and positively correlated with serum insulin (P = 0.001), leptin (P < 0.001) and HOMA2-IR (P < 0.001). Insulin resistance and alterations in adipokines might have central role in pathogenesis of hepatic steatosis after liver transplantation and can be targeted for diagnostic and therapeutic purposes.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium–glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

Range of Normal Serum Aminotransferase Levels in Liver Transplant Recipients

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are used to monitor liver transplant recipients (LTR) but the reference range and context of its use is not well defined. We aimed to determine the healthy ranges in LTR without chronic liver disease.

METHODS

One hundred and three LTR without chronic liver disease based on serology, transient elastography with controlled attenuated parameter, and ultrasound were included. A healthy range of aminotransferases was set to 95th percentile. An updated normal aminotransferase range was used to detect recurrence in post-liver transplantation (LT) with hepatitis C virus (HCV) and nonalcoholic fatty liver disease (NAFLD).

RESULTS

The normal ALT and AST range was 0 to 57 and 0 to 54 IU/L, respectively, in LTR and was not affected by age, sex, obesity, or choice of immunosuppressant. The diagnostic performance of serum ALT and AST to detect recurrence of NAFLD by a controlled attenuated parameter was poor with area under the receiver operating characteristic curve of 0.573 (95% confidence interval 0.493, 0.655; P = .08) and 0.537 (0.456, 0.618; P = .4), respectively. In contrast, the diagnostic performance of ALT and AST to detect recurrence of HCV after LT was 0.906 (0.868, 0.944; P < .001) and 0.925 (0.890, 0.959; P < .001), respectively.

CONCLUSION

The updated aminotransferase range in LTR is higher than the general population and accurate for detecting recurrent HCV, but not NAFLD.

New Insights into the Liver-Visceral Adipose Axis During Hepatic Resection and Liver Transplantation

In the last decade, adipose tissue has emerged as an endocrine organ with a key role in energy homeostasis. In addition, there is close crosstalk between the adipose tissue and the liver, since pro- and anti-inflammatory substances produced at the visceral adipose tissue level directly target the liver through the portal vein. During surgical procedures, including hepatic resection and liver transplantation, ischemia–reperfusion injury induces damage and regenerative failure. It has been suggested that adipose tissue is associated with both pathological or, on the contrary, with protective effects on damage and regenerative response after liver surgery. The present review aims to summarize the current knowledge on the crosstalk between the adipose tissue and the liver during liver surgery. Therapeutic strategies as well as the clinical and scientific controversies in this field are discussed. The different experimental models, such as lipectomy, to evaluate the role of adipose tissue in both steatotic and nonsteatotic livers undergoing surgery, are described. Such information may be useful for the establishment of protective strategies aimed at regulating the liver–visceral adipose tissue axis and improving the postoperative outcomes in clinical liver surgery.

Recurrent or De Novo Allograft Steatosis and Long-term Outcomes After Liver Transplantation

BACKGROUND

Hepatic steatosis is strongly associated with cardiovascular disease in the general population. Whether recurrent or de novo, it can occur in the allograft, but the impact on survival and long-term clinical outcomes remains unclear. In this study, we aim to determine both the frequency and impact of allograft steatosis on long-term posttransplant outcomes.

METHODS

A retrospective review of 588 adult liver transplant (LT) recipients (1999-2006) was performed. Cox regression analysis (time-dependent) was used to evaluate differences in time to steatosis post-LT, patient survival, and cardiovascular outcomes.

RESULTS

Mean age 51.9 ± 10.6 years, 64.6% males, underlying nonalcoholic steatohepatitis (NASH) (9.4%), previous tobacco (52%), pre-LT diabetes mellitus (30.3%), pre-LT hypertension (23.2%), and known cardiovascular disease (9.7%). Overall, 254 recipients developed allograft steatosis (at 10 years: 77.6% NASH recipients, 44.7% Non-NASH recipients). Risk factors for allograft steatosis were female sex (hazard ratio [HR], 1.47; 95% confidence interval [CI], 1.09-2.00; P = 0.014), hepatitis C virus diagnosis (HR, 2.49; 95% CI, 1.77-3.94; P < 0.001), and time-dependent BMI (per unit: HR, 1.08; 95% CI, 1.05-1.10; P < 0.001). Allograft steatosis was not associated with post-LT survival (P = 0.25) nor cardiovascular events (HR, 1.08; 95% CI, 0.73-1.59; P = 0.70). Underlying NASH associated with cardiovascular events (HR, 2.04; 95% CI, 1.37-3.04; P < 0.001).

CONCLUSIONS

Allograft steatosis is common but not associated with survival or cardiovascular events in this study. Larger prospective studies are needed to better define the natural history of allograft steatosis.

INSULIN RESISTANCE REDUCTION AFTER SUSTAINED VIROLOGICAL RESPONSE WITH DIRECT ACTING ANTIVIRAL:NOT EVERY POPULATION IMPROVES

BACKGROUND

Hepatitis C virus (HCV) infection is a serious public health problem, that affects approximately 170 million people worldwide. Chronic HCV infection is associated with hepatic insulin resistance and an increased risk of diabetes HCV-infected patients has been well documented.

OBJECTIVE

To assess the homeostasis model assessment of insulin resistance (HOMA-IR) index in patients treated with direct acting antiviral (DAAs) medication in the sustained virological response (SVR), categorized by the presence or absence of cirrhosis.

METHODS

A prospective study was conducted. Data were collected at the beginning of treatment (t-base) and in the twelfth week after the completion of treatment (t-SVR12). The inclusion criteria were presence of: HCV infection (RNA-HCV positive), age ≥18 years, completion of DAAs' therapy, and presence of diabetes with use of oral hypoglycemic agents. All samples were collected during the study period. The exclusion criteria were: presence of HBV/HIV co-infection, hepatocellular carcinoma at baseline, diabetic patients taking insulin and transplanted patients (liver/kidney). Fibrosis was assessed by hepatic elastography or biopsy (METAVIR). Cirrhosis was determined by clinical results or imaging. HOMA-IR was calculated as fasting insulin (μU/mL) × fasting glucose (mmol/L)/22.5) The patients were divided into two groups: the general study population (all patients, including the diabetic patients) and the special population (patients with normal values of HOMA-IR, which is >2.5, and without diabetes). The delta HOMA-IR value was calculated as: HOMA-IR at t-base - HOMA-IR at t-SVR12. For the descriptive statistical analysis, the paired t-test and generalized linear model assuming the log binding function were performed. A P value of < 0.05 was considered significant.

RESULTS

We included 150 patients, and 75 were cirrhotic. The mean age was 55.3±9.97 and body mass index was 27.4±5.18. Twenty-two (14.67%) were diabetic patients using oral hypoglycemic agents, and 17 (11%) were cirrhotic. In the general study population, the mean glucose and HOMA-IR values increased at t-SVR12, but insulin decreased. Delta HOMA-IR was negative at t-SVR12, but there was no significant difference. Excluding diabetic patients and those with normal HOMA-IR values (<2.5), mean glucose, insulin and HOMA-IR decreased at t-SVR12. Delta HOMA-IR decreased significantly at t-SVR12 (P: 0.02).

CONCLUSION

In the general population, glucose and HOMA-IR values increased at t-SVR12, but insulin decreased. In the special population, glucose, insulin, HOMA-IR and Delta HOMA-IR decreased at t-SVR12.

The Role of Adipokines in Surgical Procedures Requiring Both Liver Regeneration and Vascular Occlusion

Liver regeneration is a perfectly calibrated mechanism crucial to increase mass recovery of small size grafts from living donor liver transplantation, as well as in other surgical procedures including hepatic resections and liver transplantation from cadaveric donors. Regeneration involves multiple events and pathways in which several adipokines contribute to their orchestration and drive hepatocytes to proliferate. In addition, ischemia-reperfusion injury is a critical factor in hepatic resection and liver transplantation associated with liver failure or graft dysfunction post-surgery. This review aims to summarize the existing knowledge in the role of adipokines in surgical procedures requiring both liver regeneration and vascular occlusion, which increases ischemia-reperfusion injury and regenerative failure. We expose and discuss results in small-for-size liver transplantation and hepatic resections from animal studies focused on the modulation of the main adipokines associated with liver diseases and/or regeneration published in the last five years and analyze future perspectives and their applicability as potential targets to decrease ischemia-reperfusion injury and improve regeneration highlighting marginal states such as steatosis. In our view, adipokines means a promising approach to translate to the bedside to improve the recovery of patients subjected to partial hepatectomy and to increase the availability of organs for transplantation.

Steroid-free immunosuppression with low-dose tacrolimus is safe and significantly reduces the incidence of new-onset diabetes mellitus following liver transplantation

OBJECTIVES

Corticosteroids (CS) are traditionally used as part of the basal immunosuppression (IS) following liver transplantation (LT) but are known to be associated with an increased risk of new-onset diabetes mellitus (NODM), cardiovascular morbidity and mortality. The aim of this study was to retrospectively compare the incidence of transient as well as persistent NODM, rejection rate and patient- and graft survival between patients receiving steroid-based and steroid-free maintenance IS.

MATERIALS AND METHODS

A total of 238 patients liver transplanted (2008-2011) with deceased donor livers were divided into two groups, one group that received steroid-based IS (tacrolimus (TAC), corticosteroids (CS), ± mycophenolate mofetil (MMF); n = 155) (2008-2011) and another group of non-autoimmune recipients that received steroid-free IS (TAC, MMF; n = 83) according to our new maintenance IS-protocol starting January 2010. The primary and secondary end-points were patient- and graft survival, rejection rates and the incidence of NODM. The median follow-up times were 1248 days and 681 days, respectively.

RESULTS

The one-year patient- and graft survival in the steroid-based and steroid-free group was 92.7% and 93.3% (ns) and 87.6% and 84.9% (ns), respectively. The incidence of biopsy proven acute rejection (BPAR) was 27.7% in both groups (ns) during follow-up. The overall incidence of persistent NODM in the two groups were 16.8% and 2.9%, respectively (p < .01).

CONCLUSIONS

The results show that steroid-free low-dose tacrolimus-based IS following LT is safe and decreases the incidence of NODM significantly.

Nonalcoholic steatohepatitis in posttransplantation liver: Review article

INTRODUCTION

Nonalcoholic steatohepatitis (NASH) associated or not with cirrhosis is the third leading indication for liver transplantation (LT) around the world. After transplants, NASH has a high prevalence and occurs as both recurrent and de novo manifestations. De novo NASH can also occur in allografts of patients transplanted for non-NASH liver disease.

OBJECTIVE

To evaluate recurrent or de novo NASH in post-LT patients.

METHOD

A literature review was performed using search engines of indexed scientific material, including Medline (by PubMed), Scielo and Lilacs, to identify articles published in Portuguese and English until August 2016. Eligible studies included: place and year of publication, prevalence, clinical characteristics, risk factors and survival.

RESULTS

A total of 110 articles were identified and 63 were selected. Most of the studies evaluated recurrence and survival after LT. Survival reached 90-100% in 1 year and 52-100% in 5 years. Recurrence of NAFLD (steatosis) was described in 15-100% and NASH, in 4-71%. NAFLD and de novo NASH were observed in 18-67% and 3-17%, respectively. Metabolic syndrome, diabetes mellitus, dyslipidemia and hypertension were seen in 45-58%, 18-59%, 25-66% and 52-82%, respectively.

CONCLUSION

After liver transplants, patients present a high prevalence of recurrent and de novo NASH. They also show a high frequence of metabolic disorders. Nevertheless, these alterations seem not to influence patient survival.

Multiple genetic variants associated with posttransplantation diabetes mellitus in Chinese Han populations

OBJECTIVES

Posttransplantation diabetes mellitus (PTDM) is a major complication after solid organ transplantation. This study is to investigate the association of nine genetic variant factors and PTDM in Chinese Han patients.

METHODS

HLA-DP (rs3077, rs9277535), HLA-DQ (rs7453920), signal transducer and activator of transcription 4 (STAT4) (rs7574865), IL-28B (rs12979860, rs8099917, and rs12980275), and IL-18 (rs1946518 and rs187238) were investigated in 260 liver transplant recipients (PTDM vs non-PTDM) by high-resolution melting curve analysis. Serum interleukin (IL)-1β, IL-6, IL-8, IL-17, interferon-γ, inducible protein-10, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1b were analyzed by a Bio-Plex suspension array system (Bio-Plex Multiplex Immunoassays, Bio-Rad, Hercules, CA, USA).

RESULTS

Signal transducer and activator of transcription 4 (rs7574865) T allele and IL-18 (rs1946518) A allele increase the risk for insulin resistance and PTDM.

CONCLUSIONS

Recipients with STAT4 (rs7574865) T allele are associated with an increased concentration of IL-1β, interferon-γ, monocyte chemoattractant protein, and macrophage inflammatory protein-1b. The genetic variants of STAT4 (rs7574865) and IL-18 (rs1946518) may be new important markers for PTDM.

Fatty liver is associated with an increased risk of diabetes and cardiovascular disease - Evidence from three different disease models: NAFLD, HCV and HIV

Fatty liver, which frequently coexists with necro-inflammatory and fibrotic changes, may occur in the setting of nonalcoholic fatty liver disease (NAFLD) and chronic infections due to either hepatitis C virus (HCV) or human immunodeficiency virus (HIV). These three pathologic conditions are associated with an increased prevalence and incidence of cardiovascular disease (CVD) and type 2 diabetes (T2D). In this multidisciplinary clinical review, we aim to discuss the ever-expanding wealth of clinical and epidemiological evidence supporting a key role of fatty liver in the development of T2D and CVD in patients with NAFLD and in those with HCV or HIV infections. For each of these three common diseases, the epidemiological features, pathophysiologic mechanisms and clinical implications of the presence of fatty liver in predicting the risk of incident T2D and CVD are examined in depth. Collectively, the data discussed in this updated review, which follows an innovative comparative approach, further reinforce the conclusion that the presence of fatty/inflamed/fibrotic liver might be a shared important determinant for the development of T2D and CVD in patients with NAFLD, HCV or HIV. This review may also open new avenues in the clinical and research arenas and paves the way for the planning of future, well-designed prospective and intervention studies.

New-onset diabetes mellitus after living-donor liver transplantation: association with graft synthetic function

BACKGROUND AND PURPOSE

It is now known that post-transplant graft function after deceased-donor liver transplantation and living-donor liver transplantation (LDLT) differ; however, there is no report assessing the relationship between graft function and the development of new-onset diabetes mellitus after transplantation (NODAT). We conducted this study to identify the predictive risk factors for NODAT, including graft function after LDLT.

METHODS

The subjects of this study were 175 adult recipients who underwent LDLT at Kyoto University Hospital between 2006 and 2010, and survived for more than 3 months (median observation period, 1046 days).

RESULTS

The 1-, 2-, and 3-year incidences of NODAT after LDLT were 26.1, 32.0, and 33.4%, respectively. Pre-transplant diabetes was associated with poor survival (p = 0.0048), whereas NODAT was not associated with patient survival. In the multivariate analysis, recipient age ≥40, a tacrolimus trough level ≥8 ng/mL 3 months after LDLT, and cholinesterase (ChE) <185 IU/L 3 months after LDLT were the independent risk factors for NODAT.

CONCLUSIONS

Poor graft synthetic function 3 months after LDLT as well as older age of the recipient and a higher tacrolimus concentration were strongly associated with NODAT development after LDLT.

Higher Glucose and Insulin Levels Are Associated with Risk of Liver Cancer and Chronic Liver Disease Mortality among Men without a History of Diabetes

Insulin resistance likely increases the risk of chronic liver disease (CLD) and liver cancer, but long-term prospective studies with measured fasting glucose and insulin are lacking. We evaluated the associations of prediagnostic fasting glucose, insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR) with liver cancer and CLD mortality in a prospective study of Finnish male smokers with extended follow-up time (≤22 years) and information on known risk factors using data from 138 incident primary liver cancer cases, 216 CLD deaths, and 681 matched controls. Fasting glucose and insulin were measured in baseline serum. We used unconditional logistic regression to estimate ORs and 95% confidence intervals adjusted for age, alcohol, education, smoking, body mass index, and hepatitis B and C viral status. Among those without self-reported diabetes, glucose was positively associated with liver cancer [quartile 3 vs. quartile 1 (Q3/Q1): OR = 1.88; 1.03-3.49; Q4/Q1: OR = 2.40; 1.33-4.35; P_trend = 0.002], and undiagnosed, biochemically defined, diabetes was associated with higher risk of liver cancer (OR = 2.95; 1.46-5.96) and CLD mortality (OR = 1.88; 1.00-3.56). Serum insulin and HOMA-IR were also positively associated with liver cancer (Q4/Q1: OR = 3.41; 1.74-6.66; P_trend < 0.0001; OR = 3.72; 1.89-7.32, P_trend < 0.0001, respectively) and CLD (OR = 2.51; 1.44-4.37; P_trend = 0.0002; OR = 2.31; 1.34-3.97; P_trend = 0.001, respectively), with stronger associations observed for liver cancer diagnosed >10 years after baseline. In conclusion, elevated fasting glucose and insulin and insulin resistance were independently associated with risk of liver cancer and CLD mortality, suggesting a potentially important etiologic role for insulin and glucose dysregulation even in the absence of diagnosed diabetes. Cancer Prev Res; 9(11); 866-74. ©2016 AACR.

Metabolic complications in liver transplant recipients

The metabolic syndrome (MS), which includes obesity, dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, with a prevalence of 44%-58%. The MS, together with the immunosuppression, is considered the main risk factor for the development of cardiovascular disease (CVD) in transplant recipients, which in turn accounts for 19%-42% of all deaths unrelated to the graft. The presence of MS represents a relative risk for the development of CVD and death of 1.78. On the other hand, non-alcoholic fatty liver disease (NAFLD), considered as the manifestation of the MS in the liver, is now the second leading reason for liver transplantation in the United States after hepatitis C and alcohol. NAFLD has a high rate of recurrence in the liver graft and a direct relation with the worsening of other metabolic disorders, such as insulin resistance or diabetes mellitus. Consequently, it is vitally important to identify and treat as soon as possible such modifiable factors as hypertension, overweight, hyperlipidaemia or diabetes in transplanted patients to thus minimise the impact on patient survival. Additionally, steroid-free regimens are favoured, with minimal immunosuppression to limit the possible effects on the development of the MS.

Factors Associated with Insulin Resistance in Patients with Chronic HCV Genotype 1 Infection without Obesity or Type 2 Diabetes

OBJECTIVE

To investigate the prevalence of insulin resistance (IR) and its association with clinical parameters in patients with hepatitis C virus (HCV) genotype 1 without obesity or type 2 diabetes.

METHODS

One hundred and twenty-seven HCV-infected patients admitted to the Nutrition and Hepatology Clinic were included. Statistical analysis was performed using the Mann-Whitney test, Fisher's exact test, and Poisson regression analysis.

RESULTS

The prevalence of IR (homeostasis model assessment [HOMA]-IR ≥ 3.0) was 37.0%. The independent predictors for IR included the following: aspartate aminotransferase (AST) and alanine aminotransferase (ALT) 1.5 times the upper normal limit (odds ratio [PR] = 2.06, 95% CI, 1.16-3.66; PR = 2.32, 95% CI, 1.26-4.49, respectively); gamma glutamyl transferase (γGT) ≥ 85 U/L (PR = 2.09, 95% CI, 1.12-4.12); increased waist circumference (PR = 2.24, 95% CI, 1.25-4.17); increased waist : hip ratio (PR = 2.24, 95% CI, 1.11-5.17); increased body fat percentage (PR = 2.21, 95% CI, 1.01-5.79); overweight (PR = 2.54, 95% CI, 1.40-4.82); and metabolic syndrome (PR = 3.05, 95% CI, 1.69-5.44). High ALT levels and anthropometric parameters remained in the model of multivariate regression analysis.

CONCLUSIONS

Our findings showed a significantly high prevalence of insulin resistance in nondiabetic, nonobese patients with hepatitis C genotype 1. High ALT levels and anthropometric parameters were significantly associated with IR after multivariate regression analysis. Our data show the importance of monitoring IR, weight, and body composition in patients with chronic hepatitis C. Nutritional management seems to be important in the control of comorbidities related to excess weight and the enhancement of therapeutic responses.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Impact of new treatment options for hepatitis C virus infection in liver transplantation

Liver transplant candidates and recipients with hepatitis C virus (HCV)-related liver disease greatly benefit from an effective antiviral therapy. The achievement of a sustained virological response before transplantation can prevent the recurrence of post-transplant HCV disease that occurs universally and correlates with enhanced progression to graft cirrhosis. Previous standard-of-care regimens (e.g., pegylated-interferon plus ribavirin with or without first generation protease inhibitors, boceprevir and telaprevir) displayed suboptimal results and poor tolerance in liver transplant recipients. A new class of potent direct-acting antiviral agents (DAA) characterized by all-oral regimens with minimal side effects has been approved and included in the recent guidelines for the treatment of liver transplant recipients with recurrent HCV disease. Association of sofosbuvir with ribavirin and/or ledipasvir is recommended in liver transplant recipients and patients with decompensated cirrhosis. Other regimens include simeprevir, daclatasvir, and combination of other DAA. Possible interactions should be monitored, especially in coinfected human immunodeficiency virus/HCV patients receiving antiretrovirals.

Recipient female gender is a risk factor for graft loss after liver transplantation for chronic hepatitis C: Evidence from the prospective Liver Match cohort

BACKGROUND

Female gender has been reported to be a risk factor for graft loss after liver transplantation for hepatitis C virus (HCV)-related cirrhosis but evidence is limited to retrospective studies.

AIMS

To investigate the impact of recipient gender and donor/recipient gender mismatch on graft outcome.

METHODS

We performed a survival analysis of a cohort of 1530 first adult transplants enrolled consecutively in Italy between 2007 and 2009 and followed prospectively. After excluding possible confounding factors (fulminant hepatitis, human immunodeficiency virus co-infection, non-viremic anti-HCV positive subjects), a total of 1394 transplant recipients (604 HCV-positive and 790 HCV-negative) were included.

RESULTS

Five-year graft survival was significantly reduced in HCV-positive patients (64% vs 76%, p=0.0002); Cox analysis identified recipient female gender (HR=1.44, 95% CI 1.03-2.00, p=0.0319), Mayo clinic End stage Liver Disease score (every 10 units, HR=1.25, 95% CI 1.03-1.50; p=0.022), portal thrombosis (HR=2.40, 95% CI 1.20-4.79, p=0.0134) and donor age (every 10 years, HR=1.14, 95% CI 1.05-1.24, p=0.0024) as independent determinants of graft loss. All additional mortality observed among female recipients was attributable to severe HCV recurrence.

CONCLUSIONS

This study unequivocally shows that recipient female gender unfavourably affects the outcome of HCV-infected liver grafts.

n-3 polyunsaturated fatty acid supplementation reduces insulin resistance in hepatitis C virus infected patients: a randomised controlled trial

BACKGROUND

Insulin resistance promotes liver disease progression and may be associated with a lower response rate in treated hepatitis C virus (HCV) infected patients. n-3 polyunsaturated fatty acid (PUFA) supplementation may reduce insulin resistance. The present study aimed to evaluate the effect of n-3 PUFA supplementation on insulin resistance in these patients.

METHODS

In a randomised, double-blind clinical trial, 154 patients were screened. After applying inclusion criteria, 52 patients [homeostasis model assessment index of insulin resistance (HOMA-IR ≥2.5)] were randomly divided into two groups: n-3 PUFA (n = 25/6000 mg day(-1) of fish oil) or control (n = 27/6000 mg day(-1) of soybean oil). Both groups were supplemented for 12 weeks and underwent monthly nutritional consultation. Biochemical tests were performed at baseline and after intervention. Statistical analysis was performed using the Wilcoxon Mann-Whitney test for comparisons and the Wilcoxon test for paired data. Statistical package r, version 3.02 (The R Project for Statistical Computing) was used and P < 0.05 (two-tailed) was considered statistically significant.

RESULTS

Comparisons between groups showed that n-3 PUFA supplementation was more effective than the control for reducing HOMA-IR (P = 0.015) and serum insulin (P = 0.016). The n-3 PUFA group not only showed a significant reduction in HOMA-IR 3.8 (3.2-5.0) versus 2.4 (1.8-3.3) (P = 0.002); serum insulin 17.1 (13.8-20.6) μIU mL(-1) versus 10.9 (8.6-14.6) μIU mL(-1) (P = 0.001); and glycated haemoglobin 5.4% (5.0-5.7%) versus 5.1% (4.8-5.6%) (P = 0.011), but also presented an increase in interleukin-1 97.5 (0.0-199.8) pg mL(-1) versus 192.4 (102.2-266.8) pg mL(-1) (P = 0.003) and tumour necrosis factor 121.2 (0.0-171.3) pg mL(-1) versus 185.7 (98.0-246.9) pg mL(-1) (P = 0.003).

CONCLUSIONS

n-3 PUFA supplementation reduces insulin resistance in genotype 1 HCV infected patients.

Recurrent HCV after liver transplantation-mechanisms, assessment and therapy

Chronic HCV infection is the leading indication for liver transplantation. However, as a result of HCV recurrence, patient and graft survival after liver transplantation are inferior compared with other indications for transplantation. HCV recurrence after liver transplantation is associated with considerable mortality and morbidity. The development of HCV-related fibrosis is accelerated after liver transplantation, which is influenced by a combination of factors related to the virus, donor, recipient, surgery and immunosuppression. Successful antiviral therapy is the only treatment that can attenuate fibrosis. The advent of direct-acting antiviral agents (DAAs) has changed the therapeutic landscape for the treatment of patients with HCV. DAAs have improved tolerability, and can potentially be used without PEG-IFN for a shorter time than previous therapies, which should result in better outcomes. In this Review, we describe the important risk factors that influence HCV recurrence after liver transplantation, highlighting the mechanisms of fibrosis and the integral role of hepatic stellate cells. Indirect and direct assessment of fibrosis, in addition to new antiviral therapies, are also discussed.

Co-expression analysis of differentially expressed genes in hepatitis C virus-induced hepatocellular carcinoma

The aim of the current study was to investigate the molecular mechanisms underlying hepatitis C virus (HCV)-induced hepatocellular carcinoma (HCC) using the expression profiles of HCV-infected Huh7 cells at different time points. The differentially expressed genes (DEGs) were identified with the Samr package in R software once the data were normalized. Functional and pathway enrichment analysis of the identified DEGs was also performed. Subsequently, MCODE in Cytoscape software was applied to conduct module analysis of the constructed co-expression networks. A total of 1,100 DEGs were identified between the HCV-infected and control samples at 12, 18, 24 and 48 h post-infection. DEGs at 24 and 48 h were involved in the same signaling pathways and biological processes, including sterol biosynthetic processes and tRNA amino-acylation. There were 22 time series genes which were clustered into 3 expression patterns, and the demarcation point of the 2 expression patterns that 401 overlapping DEGs at 24 and 48 h clustered into was 24 h post-infection. tRNA synthesis-related biological processes emerged at 24 and 48 h. Replication and assembly of HCV in HCV-infected Huh7 cells occurred mainly at 24 h post-infection. In view of this, the screened time series genes have the potential to become candidate target molecules for monitoring, diagnosing and treating HCV-induced HCC.

Recurrent hepatitis C after liver transplant

End stage liver disease from hepatitis C is the most common indication for liver transplantation in many parts of the world accounting for up to 40% of liver transplants. Antiviral therapy either before or after liver transplantation is challenging due to side effects and lower efficacy in patients with cirrhosis and liver transplant recipients, as well as from drug interactions with immunosuppressants. Factors that may affect recurrent hepatitis C include donor age, immunosuppression, IL28B genotype, cytomegalovirus infection, and metabolic syndrome. Older donor age has persistently been shown to have the greatest impact on recurrent hepatitis C. After liver transplantation, distinguishing recurrent hepatitis C from acute cellular rejection may be difficult, although the development of molecular markers may help in making the correct diagnosis. The advent of interferon free regimens with direct acting antiviral agents that include NS3/4A protease inhibitors, NS5B polymerase inhibitors and NS5A inhibitors holds great promise in improving outcomes for liver transplant candidates and recipients.

The impact of diabetes mellitus and glycemic control on clinical outcomes following liver transplant for hepatitis C

Hepatitis C is the leading indication for liver transplantation in the USA and recurrence is universal. The impact of preexisting diabetes, new-onset diabetes after transplant (NODAT), and glycemic control on fibrosis progression has not been studied. This retrospective longitudinal cohort study included adult liver recipients with hepatitis C transplanted between 2000 and 2011. Patients were divided into three groups: preexisting diabetes (n = 41), NODAT (n = 59), and no diabetes (n = 103). Patients with preexisting diabetes (70%) or NODAT (59%) were more likely to develop hepatitis C recurrence (≥stage 1 fibrosis), as compared to non-diabetics (36%, p = 0.006). There was also a trend toward a higher incidence of at least Stage 2 fibrosis (36% and 48% vs. 23%, respectively; p = 0.063). Patients with tight glycemic control had a lower rate of Stage 2 fibrosis development (78% vs. 60%, p = 0.027), while those with good control (<150 mg/dL) also had lower rates of Stage 2 fibrosis (84% vs. 62%, p = 0.004). Multivariable analysis verified a decreased rate of recurrence for patients with blood glucose <138 mg/dL (p = 0.021), after controlling for confounders. These results demonstrate that diabetes is strongly associated with an increased risk of hepatitis C virus-related fibrosis development and glycemic control may reduce the risk and severity of recurrence.

Role of toll-like receptors in liver transplantation

Toll-like receptors (TLRs) are pathogen recognition receptors that orchestrate the innate immune response and the subsequent adaptive immune response. TLRs can be triggered by exogenous ligands expressed by invading pathogens or by the release of endogenous ligands, such as that occurring through cellular injury during the transplantation process. They are now recognized to play an important role in many facets of transplantation biology, including rejection and tolerance, ischemia/reperfusion injury (IRI), and infections after transplantation. The role of TLRs in liver transplantation is unique with respect to other organ transplants because the portal circulation is a continuous source of TLR2 and TLR4 ligands, and this influences TLR signaling pathways, which have a central role in transplantation immunity. This review provides a critical update on recent data outlining the important role of TLRs in liver transplantation, and there is a particular focus on emerging advances in our understanding of rejection and tolerance, IRI, and infections after transplantation and on the ways in which these events may influence the recurrence of diseases such as hepatitis C infection after liver transplantation.

Hepatitis C recurrence: the Achilles heel of liver transplantation

Hepatitis C virus (HCV) infection is the most common indication for liver transplantation worldwide; however, recurrence post transplant is almost universal and follows an accelerated course. Around 30% of patients develop aggressive HCV recurrence, leading to rapid fibrosis progression (RFP) and culminating in liver failure and either death or retransplantation. Despite many advances in our knowledge of clinical risks for HCV RFP, we are still unable to accurately predict those most at risk of adverse outcomes, and no clear consensus exists on the best approach to management. This review presents a critical overview of clinical factors shown to influence the course of HCV recurrence post transplant, with particular focus on recent data identifying the important role of metabolic factors, such as insulin resistance, in HCV recurrence. Emerging data for genetic markers of HCV recurrence and their usefulness for predicting adverse outcomes will also be explored.

Investigation of PNPLA3 and IL28B genotypes on diabetes and obesity after liver transplantation: insight into mechanisms of disease

To identify genetic risks for obesity and diabetes postliver transplantation (LT), LT recipients underwent genotyping for IL28B rs12979860 (n = 295) and PNPLA3 rs738409 (n = 205) polymorphism in both donors and recipients. The development of obesity and diabetes/impaired fasting glucose (IFG) was determined 1-5 years post-LT. Recipient PNPLA-3 genotype was independently associated with obesity (BMI > 30) at 3 years posttransplant (genotype CC 33.7%, CG 48.3% and GG 82.4%, p = 0.002), with an odds ratio (OR 2.54, CI 1.38-4.66, p = 0.003), associated with the G allele. Diabetes/IFG diagnosed within 5 years posttransplant associated with PNPLA-3 non-CC genotype (HR 1.59, 1.12-2.26, p = 0.010), but not IL28B TT genotype (HR 1.46, 0.94-2.27, p = 0.092). No genotype variable was independently predictive of diabetes/IFG. The combination of PNPLA-3 non-CC and IL28B TT genotype was associated with increased risk of diabetes/IFG compared to PNPLA-3 CC, IL28B non-TT (HR 2.64, CI 1.30-5.39, p = 0.008). Donor genotypes were not associated with any of the outcomes analyzed. In conclusion, PNPLA-3 non-CC genotype is associated with posttransplant obesity but not independently with diabetes/IFG. The lack of donor related risk suggests a peripheral rather than central mechanism of insulin resistance in liver transplant recipients.

Analysis of the recurrence of hepatitis C virus after liver transplantation: results of the Andalusian liver registry

OBJECTIVE

This study analyzed the factors related to recurrence of hepatitis C virus (HCV) among orthotopic liver transplantation (OLT) patients.

PATIENTS AND METHODS

We undertook a multicenter, prospective, observational study of OLT patients transplanted due to HCV at four Andalusian transplantation centers from 2005 to 2007. Patients were excluded if their survival was less than 1 month. The analysis included 110 pre-, peri-, and posttransplant variables that could affect HCV recurrence. We also examined the influence of cardiovascular risk factors and immunosuppression on HCV.

RESULTS

Among 121 HCV patients, 83 (69%) experienced a histologically significant recurrence of HCV, including 13 (16%) who died compared with 5 of 38 (13%) who did not show a severe recurrence of HCV (P = .3). The mean follow-up was 44 months (range, 4 to 64 months). The mean time to appearance of the relapse was 9 months (range, 1 to 40 months) with no differences according to the type of immunosuppression. Of all study variables, donor age (> 52 years) showed a trend for greater recurrence (P = .1). The use of powerful immunosuppression (three or more drugs), either as induction or as sustained therapy, during the first posttransplantation year was significantly associated with a greater relapse rate (P < .01), albeit with no significant difference according to the type of calcineurin inhibitor. Mycophenolate mofetil was not associated with a greater posttransplantation viral load or earlier relapse, although its use in multiple immunosuppression schedules was associated with a greater relapse rate (P < .01). Survival of patients with recurrent HCV was reduced, although not significantly. Multivariate analysis showed a 4.4 times greater risk for developing de novo diabetes mellitus (DM) among patients with a severe relapse of HCV.

CONCLUSIONS

There was an important trend toward a greater recurrence rate of HCV among patients who received powerful immunosuppression protocols, particularly during the first 12 months. Special attention should be given to the risk for de novo DM among HCV-positive patients.

Insulin resistance, steatosis and hepatitis C virus

Epidemiological studies have shown an increased occurrence of metabolic disorders such as insulin resistance (IR) and steatosis in patients with hepatitis C virus (HCV) infection. IR is believed to represent one of the central clinical features of the "metabolic syndrome" and the major pathogenetic factor for type 2 diabetes mellitus. In patients with chronic HCV hepatitis, IR may have several dangerous consequences such as accelerated progression of liver fibrosis, resistance to antiviral therapy and development of hepatocellular carcinoma. According to recent evidence, the global epidemic of metabolic disorders related to incorrect diets will lead physicians to deal with 1.2 billion patients with diabetes in the world in 2025. Given the high prevalence of HCV infection in several countries, metabolic manifestations will contribute to increasing morbidity and mortality in patients with HCV chronic infection in the near future. HCV treatment, shown able to decrease both the occurrence of HCV-related IR and diabetes, may reduce the risk of the associated morbidities.

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.

Nonalcoholic fatty liver disease following liver transplantation

Post-transplant, nonalcoholic hepatic steatosis and steatohepatitis are increasingly recognized as a complication of liver transplantation, and the progression of the latter through fibrosis to cirrhosis has been clearly shown. Non-alcoholic steatohepatitis (NASH) is independently associated with an increased risk of death from cardiovascular and liver diseases. While optimal therapy is not yet available in the post-liver transplant setting, knowledge gained in the therapy of NASH in the non-transplant setting can be used to design therapeutic interventions. In addition, early recognition with protocol liver biopsies and an effective preventive strategy by modifying known risk factors implicated in the recurrence of NASH would be the most effective way to curtail the progression of NASH before an effective treatment can be found. Additional rigorous research aimed at elucidating the pathogenesis, natural history, and selection of immunosuppressants for NASH is clearly warranted.

Management of recurrent hepatitis C in orthotopic liver transplant recipients

End-stage liver disease and hepatocellular carcinoma from chronic hepatitis C are the most common indications for orthotopic liver transplantation and the incidence of both are projected to increase over the next decade. Recurrent hepatitis C virus infection of the allograft is associated with an accelerated progression to cirrhosis, graft loss, and death. This article presents an overview of the natural history of hepatitis C virus recurrence in liver transplant recipients and guidance on optimal management strategies.

Distinct microRNA profiles are associated with the severity of hepatitis C virus recurrence and acute cellular rejection after liver transplantation

Recurrent hepatitis C virus (HCV) infection is associated with accelerated fibrosis rates after liver transplantation (LT) and is the leading cause of graft failure. Furthermore, distinguishing recurrent HCV from acute cellular rejection (ACR) can be problematic, and this can lead to inappropriate treatments and adverse outcomes. We hypothesized that intragraft microRNA (miRNA) expression profiles could distinguish the severity of recurrent HCV and differentiate recurrent HCV from ACR. We established meticulously matched post-LT patient cohorts in order to derive robust global miRNA expression profiles and minimize the impact of variables known to influence HCV recurrence. These cohorts consisted of patients with slow HCV fibrosis progression (Ishak stage < F2), fast HCV fibrosis progression (Ishak stage ≥ F2), ACR, and nonviral etiologies. We found increased intragraft expression of miRNA-146a, miRNA-19a, miRNA-20a, and miRNA-let7e in slow progressors versus fast progressors, and we validated these findings with quantitative PCR. This miRNA network regulates the expression of cardinal genes implicated in promoting antifibrogenic, antiangiogenic, and anti-inflammatory pathways. miRNA-19a and miRNA-20a were also specifically detected in the serum of slow progressors. Furthermore, intragraft miRNA expression distinguished fast HCV progression from ACR. Here, changes in the expression of key miRNAs regulating fibrogenic and angiogenic pathways were associated with fast HCV progression. We demonstrate specific miRNA expression signatures that discriminate the rates of fibrosis progression in patients with recurrent HCV, and we distinguish recurrent HCV from ACR after LT. A pathway analysis indicates that specific miRNAs may play a regulatory role in these processes. Selected miRNAs may serve as intragraft and serum biomarkers for recurrent HCV after LT and help to distinguish between ACR and recurrent HCV.

A 24-week dietary and physical activity lifestyle intervention reduces hepatic insulin resistance in the obese with chronic hepatitis C

BACKGROUND/AIMS

Obesity- and virus-mediated insulin resistance (IR) are associated with adverse hepatic and metabolic outcomes in chronic hepatitis C (CHC). This study evaluates the tolerability and effects of a dietary and physical activity (PA) intervention in obese patients with insulin-resistant CHC.

METHODS

Obese patients (body mass index, BMI ≥30 kg/m(2) ) with CHC were recruited prospectively. Non-diabetic patients with IR (homeostasis model assessment of IR, HOMA-IR >2.0) proceeded to a 24-week lifestyle intervention comprising pedometer monitored increase in PA (≥10 000 steps/day) and an individualised dietary plan.

RESULTS

Ten non-cirrhotic and six cirrhotic patients [age 52 ± 8.5 years, BMI 35.9 (31.46-38.21)kg/m(2) ] were recruited, of whom all 16 (100%) completed the 24-week protocol. Increase in PA from 6853 (2440-9533) to 10 697 (7959-13566) steps/day (P = 0.001) and reduction in caloric intake from 2263 (1805.4-2697.0) to 1281 (1099.5-1856.3) kcal/day (equivalent to reduction of median 33% (25.3-49.8%), P < 0.001) were achieved. These behaviour changes led to a BMI reduction to 31.21 (28.72-36.10) (P < 0.001) and the HOMA-IR fell from 3.62 (2.75-4.87) to 2.08 (1.82-3.59) (P = 0.002). The hepatic insulin sensitivity index (ISI) improved significantly, but the skeletal muscle ISI did not. At week 24, 8/16 (50%) patients were no longer insulin-resistant (P = 0.008).

CONCLUSIONS

This 24-week intervention reduced BMI and reversed IR in significant proportion of patients. Such adjunctive therapy may improve hepatic and metabolic status in obese insulin-resistant CHC.

Recurrent hepatitis C virus infection post liver transplantation: impact of choice of calcineurin inhibitor

Recurrence of hepatitis C virus infection following liver transplantation (LT) for hepatitis C is universal. After LT, hepatitis C is associated with accelerated fibrosis progression and reduced graft and patient survival. Furthermore, responses to antiviral therapy in patients with recurrent hepatitis C virus post-transplant are consistently sub-optimal. Calcineurin inhibitors (CNIs) like cyclosporine A (CsA) and tacrolimus continue to dominate immunosuppressive regimens in this population; however, there is still uncertainty as to whether either offers an advantage in terms of patient outcomes. Although tacrolimus demonstrates improved efficacy in the general LT population, differences have begun to emerge between these agents regarding diabetogenic potential, antiviral activity, and fibrosis progression in patients with hepatitis C. This review critically evaluates the existing literature, providing an overview of the reported differences, concluding that despite conflicting evidence, a potential benefit of CsA in patients with hepatitis C is supported by the data and warrants further investigation. Future studies examining the role of CNIs in hepatitis C virus-positive LT recipients are required to accurately examine the effects of CNIs on outcomes such as fibrosis progression, survival, and effects on response to antiviral therapy, to provide robust information that allows clinicians to make an informed choice concerning which CNI is best for their patients.

Living-donor liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompression. In areas with low deceased-donor organ availability like Japan, living-donor liver transplantation (LDLT) is similarly indicated for HCV cirrhosis as deceased-donor liver transplantation (DDLT) in Western countries and accepted as an established treatment for HCV-cirrhosis, and the results are equivalent to those of DDLT. To prevent graft failure due to recurrent hepatitis C, antiviral treatment with pegylated-interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. In contrast to DDLT, many Japanese LDLT centers have reported modified treatment regimens as best efforts to secure first graft, such as aggressive preemptive antiviral treatment, escalation of dosages, and elongation of treatment duration.

Interleukin-28B polymorphism in hepatitis C and liver transplantation

The discovery of interleukin-28B (IL-28B) single-nucleotide polymorphisms has opened an important new area of research in liver transplantation (LT) for hepatitis C virus (HCV). Both recipient- and donor-derived IL-28B genotypes affect the post-LT treatment response, with sustained virological response (SVR) rates oscillating from >50% in homozygotes for the favorable allele (up to 90% when this is present in both the recipient and the donor) to <15% in homozygotes for the unfavorable allele and from 30% to 50% in heterozygotes. Other key posttransplant outcomes affected by the IL-28B genotype are the time to histological recurrence, HCV RNA and alanine aminotransferase levels, histological variables (including the rate of fibrosis progression), and hepatocellular carcinoma. Interactions between donor and recipient IL-28B genotypes are complex and may affect outcomes not directly related to HCV infections, such as acute cellular rejection (ACR) and metabolic diseases. A preferential allocation system in which livers from donors homozygous for the favorable allele are given to HCV patients might be postulated to improve SVR rates and post-LT outcomes in recipients with HCV infections (a 25% increase in SVR and an 8% decrease in mortality at 5 years). Although negative effects from this are difficult to predict, they could include an accelerated progression of fibrosis in patients with failed HCV eradication and an increase in ACR in non-HCV patients. Our knowledge of the precise role of IL-28B genotypes in the course of post-LT HCV is evolving, but existing knowledge suggests the possibility of exploring strategies that use IL-28B genotyping to reduce the impact of post-LT adverse outcomes.

Effect of maintenance immunosuppressive drugs on virus pathobiology: evidence and potential mechanisms

Recent evidence suggesting a potential anti-CMV effect of mTORis is of great interest to the transplant community. However, the concept of an immunosuppressant with antiviral properties is not new, with many accounts of the antiviral properties of several agents over the years. Despite these reports, to date, there has been little effort to collate the evidence into a fuller picture. This manuscript was developed to gather the evidence of antiviral activity of the agents that comprise a typical immunosuppressive regimen against viruses that commonly reactivate following transplant (HHV1 and 2, VZV, EBV, CMV and HHV6, 7, and 8, HCV, HBV, BKV, HIV, HPV, and parvovirus). Appropriate immunosuppressive regimens posttransplant that avoid acute rejection while reducing risk of viral reactivation are also reviewed. The existing literature was disparate in nature, although indicating a possible stimulatory effect of tacrolimus on BKV, potentiation of viral reactivation by steroids, and a potential advantage of mammalian target of rapamycin (mTOR) inhibition in several viral infections, including BKV, HPV, and several herpesviruses.

Hepatitis C virus recurrence and immunosuppression-free state after liver transplantation

HCV-related disease is the most common indication for liver transplantation (LT). HCV recurrence, which is almost universal, has a significant impact on patient and graft survival after LT and still represents a great unsolved issue for the liver transplant community. Several treatment strategies have been proposed. Since antiviral therapy has limited efficacy and can be administrated only in selected transplant recipients and additionally that immunosuppressive drugs have a negative impact on HCV re-infection, the achievement of an immunosuppression-free state after LT could play a central role in the avoidance of rapid HCV recurrence.

The adverse pharmacology of calcineurin inhibitors and their impact on hepatitis C recurrence after liver transplantation: implications for clinical practice

Calcineurin inhibitors are widely used as maintenance immunosuppressants in solid-organ transplantation to minimize the risk of allograft rejection. Although the use of these agents has transformed the outcomes for patient and graft survival, this has come at a cost, notably the well-known adverse events of nephrotoxicity and metabolic abnormalities, to name a few. Over the last decade, tremendous interest has also focused on the impact of these medications on the replication of hepatitis C virus (HCV), with cyclosporine in particular having a negative effect on viral replication in vitro. Although small retrospective studies suggested that there may be a beneficial effect with cyclosporine on the progression of recurrent HCV and response to interferon, these findings have not been validated in several well-designed randomized controlled trial studies. The authors will review the pharmacology and pharmacokinetics of these well-known drugs and discuss the impact of these medications on the natural history of HCV recurrence after liver transplantation.

Hepatitis C virus infection in the immunocompromised host: a complex scenario with variable clinical impact

The relationship between Hepatitis C Virus (HCV) infection and immunosuppression is complex and multifaceted. Although HCV-related hepatocytolysis is classically interpreted as secondary to the attack by cytotoxic T lymphocytes against infected cells, the liver disease is usually exacerbated and more rapidly evolutive in immunosuppressed patients. This generally occurs during the immunosuppression state, and not at the reconstitution of the host response after immunosuppressive therapy discontinuation. The field of immunosuppression and HCV infection is complicated both by the different outcome observed in different situations and/or by contrasting data obtained in the same conditions, with several still unanswered questions, such as the opportunity to modify treatment schedules in the setting of post-transplant follow-up. The complexity of this field is further complicated by the intrinsic tendency of HCV infection in itself to lead to disorders of the immune system. This review will briefly outline the current knowledge about the pathogenesis of both hepatic and extrahepatic HCV-related disorders and the principal available data concerning HCV infection in a condition of impairment of the immune system. Attention will be especially focused on some conditions - liver or kidney transplantation, the use of biologic drugs and cancer chemotherapy - for which more abundant and interesting data exist.

Liver transplantation in the setting of chronic HCV

Recurrent HCV disease is the most common cause of graft loss and patient mortality in HCV-infected liver transplant (LT) recipients. Risk factors for more severe recurrence that are potentially modifiable are older donor age, prolonged cold ischaemia time, prior treated acute rejection, CMV hepatitis, IL28B donor genotype, and post-LT insulin resistance. The most effective means of preventing HCV recurrence is eradicating HCV prior to LT. Select wait-list candidates with compensated or mildly decompensated disease can be considered for antiviral treatment with peginterferon, ribavirin (and protease inhibitor if genotype 1). For the majority of LT patients, HCV treatment must be delayed until post-transplant. Treatment is generally undertaken if histologic severity reaches grade 3 or 4 necroinflammation or stage ≥2 fibrosis, or if cholestatic hepatitis. Achievement of sustained viral response (SVR) post-LT is associated with stabilization of fibrosis and improved graft survival. SVR is attained in ~30% of patients treated with peginterferon and ribavirin. Poor tolerability of therapy is a limitation. Combination therapy with telaprevir or boceprevir added to peginterferon and ribavirin is anticipated to increase efficacy but with higher rates of adverse effects and challenges in managing drug-drug interactions between the protease inhibitors and calcineurin inhibitors/sirolimus.

Long-term medical management of the liver transplant recipient: what the primary care physician needs to know

Recognition, management, and prevention of medical complications and comorbidities after liver transplant is the key to improved long-term outcomes. Beyond allograft-related complications, metabolic syndrome, cardiovascular disease, renal dysfunction, and malignancies are leading causes of morbidity and mortality in this patient population. Primary care physicians have an important role in improving outcomes of liver transplant recipients and are increasingly relied on for managing these complex patients. This review serves to assist the primary care physician in the long-term management issues of liver transplant recipients.