Epidemiology of Hepatitis C Virus: A Battle on New Frontiers

Liver Disease-Associated Glomerulopathies

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infect a significant number of individuals globally and their extra-hepatic manifestations, including glomerular disease, are well established. Additionally, liver disease-associated IgA nephropathy is the leading cause of secondary IgA nephropathy with disease course varying from asymptomatic urinary abnormalities to progressive kidney injury. Herein we provide an updated review on the epidemiology, pathogenesis, clinical manifestations, and treatment of HBV- and HCV-related glomerulonephritis as well as IgA nephropathy in patients with liver disease. The most common HBV-related glomerulonephritis is membranous nephropathy, although membranoproliferative glomerulonephritis and podocytopathies have been described. The best described HCV-related glomerulonephritis is cryoglobulinemic glomerulonephritis occurring in about 30% of patients with mixed cryoglobulinemic vasculitis. The mainstay of treatment for HBV-GN and HCV-GN is antiviral therapy, with significant improvement in outcomes since the emergence of the direct-acting antivirals. However, cases with severe pathology and/or a more aggressive disease trajectory can be offered a course of immunosuppression, commonly anti-CD20 therapy, particularly in the case of cryoglobulinemic glomerulonephritis.

Value of Triage Treatment Strategies to Distribute Hepatitis C Direct-Acting Antiviral Agents in an Integrated Healthcare System: A Cost-Effectiveness Analysis

OBJECTIVES

This study aimed to assess the cost-effectiveness of fibrosis-based direct-acting antiviral treatment policies for patients with chronic hepatitis C virus at the Kaiser Permanente Mid-Atlantic States health system.

METHODS

We used a Markov model to compare the lifetime costs and effects of treating patients with chronic hepatitis C virus at different stages of disease severity, or all stages simultaneously, based on a fibrosis score from the US healthcare sector perspective and societal perspective. The initial distribution of patients across fibrosis scores, the effectiveness of direct-acting antiviral therapy, and follow-up and monitoring protocols were specific to the Kaiser Permanente Mid-Atlantic States health system. Direct and indirect costs, transition probabilities, and utilities were derived from the literature. Deterministic and probabilistic sensitivity analyses were performed to assess the robustness of our results.

RESULTS

The "Treat All" option was dominant from both the societal and healthcare sector perspectives. The conclusion was robust in deterministic sensitivity analysis. The range of incremental costs between the less restrictive policies was small-the difference between the "Treat F1+" and the "Treat All" option was only $111 per person. Probabilistic sensitivity analyses showed, at both the $100 000/quality-adjusted life-year and $150 000/quality-adjusted life-year thresholds, there was a 70% chance that the "Treat All" option was more cost-effective than the "Treat F1+" option.

CONCLUSIONS

We found that expanded treatment access is cost-effective and, in many cases, cost saving. Although our results are primarily applicable to a regional integrated healthcare system, it offers some direction to any healthcare setting faced with resource constraints in the face of highly priced drugs.

Updated Pathway to Micro-elimination of Hepatitis C Virus in the Hemodialysis Population

Chronic hepatitis C virus (HCV) infection continues to be transmitted to hemodialysis (HD) patients within HD facilities globally. The goal of the World Health Organization to micro-eliminate HCV infection from the HD population by the year 2030 is not on target to be achieved. Obstacles to eliminate HCV in HD settings remain daunting due to a complex system created by a confluence of guidelines, legislation, regulation, and economics. HCV prevalence remains high and seroconversion continues among the HD patient population globally as a result of the HD procedure. Preventive strategies that effectively prevent HCV transmission, treatment-as-prevention, and rapid referral to treatment balanced with kidney transplant candidacy should be added to the current universal precautions approach. A safer system must be designed before HCV transmission can be halted and eliminated from the HD population.

Community-based sero-prevalence of hepatitis B and C infections in South Omo Zone, Southern Ethiopia

Background

Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) are the leading causes of liver-related morbidity and mortality throughout the world. The magnitude of HBV and HCV infections in Ethiopia has not been well studied at community level. This study aimed at investigating the sero-prevalence and associated risk factors of HBV and HCV among HBV unvaccinated community members in South Omo Zone, Southern Ethiopia.

Methods

A community-based cross-sectional study was conducted in three districts from March to May 2018. Structured questionnaire was used to collect relevant clinical and socio-demographic data. Three milliliter of blood sample was collected from each study participant and screened for HBV and HCV using one step hepatitis B surface antigen (HBsAg) test strip and one step HCV test strip, respectively. Samples found positive for HBsAg were further tested using immunoassay of Alere Determine^TM HBsAg (Alere Inc., USA). Data were analyzed using SPSS version 25.0.

Results

A total of 625 (51.4% males, age 6–80 years, mean age ± SD = 30.83 ± 13.51 years) individuals participated in the study. The sero-prevalence for HBV infection was 8.0% as detected using one step HBsAg test strip, while it was 7.2% using Alere Determine^TM HBsAg test. The sero-prevalence for HCV infection was 1.9%. Two (0.3%) of the participants were seropositive for both HBV and HCV infections. High sero-prevalence for HBV infection was associated with weakness and fatigue (AOR = 5.20; 95% CI: 1.58, 17.15), while high sero-prevalence of HCV infection was associated with age group between 46 and 65 years (AOR = 13.02; 95% CI: 1.11, 152.41).

Conclusion

This study revealed higher-intermediate endemicity level of HBV infection and low to intermediate endemicity level of HCV infection in the study area. Clinical symptoms like weakness and fatigue were found to be indictors for HBV infection, while individuals in the age group between 46 and 65 years were at higher risk for HCV infection. Provision of community- based health education; vaccination, mass screening and providing treatment would have utmost importance in reducing the transmission of these diseases in the present study area.

Severe Guillain-Barré syndrome associated with chronic active hepatitis C and mixed cryoglobulinemia: a case report

Background

We describe a case of severe Guillain-Barre syndrome (GBS) associated with chronic active hepatitis C and mixed cryoglobulinemia (MC). To our knowledge, this association between GBS and hepatitis C virus (HCV) infection has been rarely reported.

Case presentation

A 56-year-old man developed symmetrical muscle weakness in all extremities, areflexia and sensorial disorder followed by acute respiratory failure associated with chronic active hepatitis C, which was confirmed by the presence of anti-HCV antibodies in the serum and persistence of HCV RNA viral load for more than 6 months. Chronic hepatitis C was further complicated by type 3 MC. Electromyography showed peripheral nerve injury (mainly in axon). A severe acute motor sensory axonal neuropathy (AMSAN) was diagnosed. After treatment with intravenous immunoglobulin and plasma exchange followed by antiviral therapy by direct-acting antiviral agent, patient showed progressive recovery and was transferred 3 months after his first admission to a rehabilitation center.

Conclusions

Our case reported a severe GBS associated with HCV infection and MC. EMG classified for the first time the subtype of GBS (severe AMSAN) correlated with severe clinical form. HCV infection should be screened in high-risk patients to prevent silent progression of the chronic hepatitis C and its potentially severe extra-hepatic manifestations.

Autoantibodies in chronic hepatitis C virus infection: impact on clinical outcomes and extrahepatic manifestations

Goals

To examine the role that autoantibodies (auto-abs) play in chronic hepatitis C virus (HCV) regarding demographics, presence of extrahepatic manifestations and long-term outcomes in a large US cohort.

Background

Auto-abs have been reported to be prevalent in patients with chronic HCV infection, but data on the natural history of these patients are limited.

Study

The study included 1556 consecutive patients with HCV without concurrent HIV and/or HBV who had testing for antinuclear antibody (ANA), antimitochondrial antibody (AMA), antismooth muscle antibody (ASMA) and/or antiliver kidney microsomal antibody (LKM). Primary outcomes included development of cirrhosis, hepatic decompensations, hepatocellular carcinoma (HCC), mortality and/or sustained virological response (SVR) to antiviral therapy.

Results

A total of 388 patients tested positive for any auto-ab (ANA 21.8%, ASMA 13.3%, AMA 2.2% and LKM 1.2%). Patients who tested positive versus negative were more likely to be women (29.3% vs 20.9%, p<0.001) and less likely to achieve SVR with most treated patients receiving interferon-based therapies (37.2% vs 47.1%, p=0.031). There was no difference between groups for baseline laboratory data, disease state or rate of extrahepatic manifestations (42.8% vs 45.0%, p=0.44). Kaplan-Meier analysis revealed no statistically significant difference between groups for the 10-year development of cirrhosis, hepatic decompensations, HCC nor survival. Furthermore, auto-ab positivity was only found to be a predictor for a lower rate of SVR on multivariate analysis (adjusted OR=1.61, 95 %  CI 1.00 to 2.58, p=0.048).

Conclusions

In our cohort, auto-ab positivity was common, especially in women, and predicted a lower rate of SVR but otherwise had no impact on the natural history of chronic HCV or presence of extrahepatic manifestations.

Tumour virus epidemiology

A viral etiology of cancer was first demonstrated in 1911 by Peyton Rous who injected cell-free filtrate from a chicken sarcoma into healthy chickens and found it induced a tumour. Since the discovery over 50 years ago of the Epstein-Barr virus as the cause of Burkitt lymphoma, seven other human viruses or groups of viruses-hepatitis B virus, hepatitis C virus, human immunodeficiency virus type 1, some human papillomaviruses, human T-cell lymphotropic virus type 1, Kaposi sarcoma-associated herpesvirus and Merkel cell polyomavirus-have been linked to human cancer. Collectively, these eight viruses cause over 20 different types of cancer and contribute to 10-12% of all cancer, with a greater burden in low- and middle-income countries. For many viruses, immunosuppression greatly increases the risks of persistent infection, development of chronic sequelae and cancer. Although several viruses share similar routes of transmission (especially sexual activity, injection drug use and mother-to-child transmission), the predominant route of transmission varies across viruses, and for the same virus can vary by geographical location. In general, vulnerable populations at the greatest risk for viral infections and their associated diseases include people, especially children, living in low- to middle-income countries, men who have sex with men, people who use injection drugs and female sex workers.This article is part of the themed issue 'Human oncogenic viruses'.

In an era of highly effective treatment, hepatitis C screening of the United States general population should be considered

BACKGROUND & AIMS

Hepatitis C virus (HCV) treatment with all oral direct acting antiviral agents (DAA's) achieve sustained virologic response (SVR) rates of 98%. Re-assessment of general US population screening for HCV is imperative. This study compared the cost-effectiveness (CE) of three HCV screening strategies: screen all (SA), screen Birth Cohort (BCS), and screen high risks (HRS).

METHODS

Using a previous designed decision-analytic Markov model, estimations of the natural history of HCV and CE evaluation of the three HCV screening strategies over a lifetime horizon in the US population was undertaken. Based on age and risk status, 16 cohorts were modelled. Health states included: Fibrosis stages 0 to 4, decompensated cirrhosis, hepatocellular carcinoma, LT, post-LT, and death. The probability of liver disease progression was based on the presence or absence of virus. Treatment was with approved all-oral DAAs; 86% were assumed to be seen annually by a primary care provider; SVR rates, transition probabilities, utilities, and costs were from the literature. One-way sensitivity analyses tested the impact of key model drivers.

RESULTS

SA cost $272.0 billion [$135 279 per patient] and led to 12.19 QALYs per patient. BCS and HRS cost $274.5 billion ($136 568 per patient) and $284.5 billion ($141 502 per patient) with 11.65 and 11.25 QALYs per patient respectively. Compared to BCS, SA led to an additional 0.54 QALYs per patient and saved $2.59 billion; compared to HRS, SA led to 0.95 additional QALYs per patient and saved $12.5 billion.

CONCLUSIONS

Screening the entire US population and treating active viraemia was projected as cost-saving.

Viral-Associated GN: Hepatitis C and HIV

Viruses are capable of inducing a wide spectrum of glomerular disorders that can be categorized on the basis of the duration of active viremia: acute, subacute, or chronic. The variable responses of the adaptive immune system to each time period of viral infection results mechanistically in different histologic forms of glomerular injury. The unique presence of a chronic viremic carrier state with either hepatitis C (HCV) or HIV has led to the opportunity to study in detail various pathogenic mechanisms of viral-induced glomerular injury, including direct viral infection of renal tissue and the development of circulating immune complexes composed of viral antigens that deposit along the glomerular basement membrane. Epidemiologic data show that approximately 25%-30% of all HIV patients are coinfected with HCV and 5%-10% of all HCV patients are coinfected with HIV. This situation can often lead to a challenging differential diagnosis when glomerular disease occurs in this dual-infected population and requires the clinician to be familiar with the clinical presentation, laboratory workup, and pathophysiology behind the development of renal disease for both HCV and HIV. Both of these viruses can be categorized under the new classification of infection-associated GN as opposed to being listed as causes of postinfectious GN as has previously been applied to them. Neither of these viruses lead to renal injury after a latent period of controlled and inactive viremia. The geneses of HCV- and HIV-associated glomerular diseases share a total dependence on the presence of active viral replication to sustain renal injury so the renal disease cannot be listed under "postinfectious" GN. With the new availability of direct-acting antivirals for HCV and more effective combined antiretroviral therapy for HIV, successful remission and even regression of glomerular lesions can be achieved if initiated at an early stage.

Value of Treating All Stages of Chronic Hepatitis C: A Comprehensive Review of Clinical and Economic Evidence

INTRODUCTION

The goal of chronic hepatitis C (CHC) treatment is to achieve a sustained virologic response (SVR). The new generation of direct-acting antivirals (DAAs) offers 90-100% SVR rates. However, access to these treatments is generally limited to patients with advanced liver disease. The aim of this review is to provide an overview of the clinical and economic benefits of achieving SVR and to better understand the full value of CHC treatment in all stages of liver disease.

METHODS

A comprehensive literature review was performed using the PubMed, Embase, and Cochrane library databases to identify articles examining the clinical, economic, and quality of life benefits associated with SVR. Articles were limited to those published in English language from January 2006 through January 2016. Inclusion criteria were (1) patients with CHC, (2) retrospective and prospective studies, (3) reporting of mortality, liver morbidity, extrahepatic manifestations (EHMs), and economic outcomes and, (4) availability of an abstract or full-text publication.

RESULTS

Overall this review identified 354 studies involving more than 500,000 CHC patients worldwide. Evidence from 38 studies (n = 73,861) shows a significant mortality benefit of achieving SVR in patients with all stages of fibrosis. Long-term studies with follow-up of 5-12 years suggest that, particularly among non-cirrhotic patients, there is a significant decrease in mortality in SVR versus non-SVR groups. Ninety-nine studies conducted in 235,891 CHC patients in all stages of fibrosis show that SVR reduces liver-related mortality, incidence of hepatocellular carcinoma (HCC), and decompensation. A total of 233 studies show that chronic HCV infection is associated with several serious EHMs, some of which can have high mortality. Evidence from four modeling studies shows that delaying treatment to CHC patient populations could significantly increase mortality, morbidity, and medical costs.

CONCLUSIONS

There is a robust body of evidence demonstrating diverse sources of value from achieving SVR in all stages of liver disease. While access to treatment is generally limited to late-stage patients, less restrictive treatment strategies that target HCV eradication have the potential to abate the burdens of mortality, liver morbidity and extrahepatic manifestations, and the associated healthcare costs.

State of the Art, Unresolved Issues, and Future Research Directions in the Fight against Hepatitis C Virus: Perspectives for Screening, Diagnostics of Resistances, and Immunization

Hepatitis C virus (HCV) still represents a major public health threat, with a dramatic burden from both epidemiological and clinical points of view. New generation of direct-acting antiviral agents (DAAs) has been recently introduced in clinical practice promising to cure HCV and to overcome the issues related to the interferon-based therapies. However, the emergence of drug resistance and the suboptimal activity of DAAs therapies against diverse HCV genotypes have been observed, determining treatment failure and hampering an effective control of HCV spread worldwide. Moreover, these treatments remain poorly accessible, particularly in low-income countries. Finally, effective screening strategy is crucial to early identifying and treating all HCV chronically infected patients. For all these reasons, even though new drugs may contribute to impacting HCV spread worldwide a preventive HCV vaccine remains a cornerstone in the road to significantly reduce the HCV spread globally, with the ultimate goal of its eradication. Advances in molecular vaccinology, together with a strong financial, political, and societal support, will enable reaching this fundamental success in the coming years. In this comprehensive review, the state of the art about these major topics in the fight against HCV and the future of research in these fields are discussed.

Hepatitis C: global epidemiology and strategies for control

It is estimated that globally there are approximately 100 million persons with serological evidence of current or past HCV infection, and that HCV causes about 700 000 deaths each year. The prevalence of infection is the highest in lower and middle income countries, in which a significant number of past infections were caused by iatrogenic transmission and sub-optimal injection safety. In contrast, in developed countries, infections are caused mainly by high-risk exposures and behaviours among specific populations, such as persons who inject drugs. Recently, new direct antiviral activity (DAA) oral drugs with high rates of cure over short duration, which are well tolerated, have made chronic hepatitis C a curable condition. The extraordinary clinical performance of DAAs and recent substantial price reductions and expansion in access in resource-limited settings has provided new impetus for potential control and elimination of hepatitis C as a public health threat. We review the global epidemiology of HCV and the opportunities for preventative and treatment interventions to achieve global control of HCV infection. We also summarize the key elements of the World Health Organization's first-ever global health sector strategy for addressing the viral hepatitis pandemic.

Ledipasvir/sofosbuvir-based treatment of patients with chronic genotype-1 HCV infection and cirrhosis: results from two Phase II studies

BACKGROUND

Ledipasvir/sofosbuvir ± ribavirin administered for 12 weeks to patients with genotype-1 HCV infection and compensated cirrhosis is effective and well-tolerated. The Phase II TRILOGY-1 and TRILOGY-2 studies investigated whether ledipasvir/sofosbuvir plus the non-nucleotide NS5B inhibitor GS-9669 or the NS3/4A protease inhibitor vedroprevir could reduce treatment duration and/or eliminate the need for ribavirin in genotype-1 HCV-infected patients with compensated cirrhosis.

METHODS

In TRILOGY-1, 100 cirrhotic patients were randomized (1:1:1) to 8 weeks of ledipasvir/sofosbuvir plus ribavirin, ledipasvir/sofosbuvir plus GS-9669 250 mg or ledipasvir/sofosbuvir plus GS-9669 500 mg. In TRILOGY-2, 46 previously treated cirrhotic patients were randomized (1:1) to 8 weeks of ledipasvir/sofosbuvir plus vedroprevir ± ribavirin. The primary end points were the proportion of patients with sustained virological response 12 weeks after treatment discontinuation (SVR12) and safety.

RESULTS

In both studies, most patients were male (each 65%) and white (92-96%), infected with HCV genotype-1a (62-70%) and had IL28B non-CC genotypes (82-87%). In total, 37-39% of patients were Hispanic or Latino. SVR12 rates were similar across treatment arms in TRILOGY-1 (82-91%) and TRILOGY-2 (88-95%); no patient had on-treatment virological failure. Two serious adverse events (acute myocardial infarction and cardiomyopathy) were reported in two patients participating in TRILOGY-1, both of whom had pre-existing cardiac conditions. Laboratory abnormalities were infrequent.

CONCLUSIONS

All ledipasvir/sofosbuvir-based regimens were well-tolerated. To shorten therapy and eliminate ribavirin, use of a more potent third agent or a third agent with a different mechanism of action may be required.

Type 2 Diabetes in Non-Alcoholic Fatty Liver Disease and Hepatitis C Virus Infection--Liver: The "Musketeer" in the Spotlight

The pathogenesis of type 2 diabetes (T2D) involves chronic hyperinsulinemia due to systemic and hepatic insulin resistance (IR), which if uncorrected, will lead to progressive pancreatic beta cell failure in predisposed individuals. Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of fatty (simple steatosis and steatohepatitis) and non-fatty liver changes (NASH-cirrhosis with or without hepatocellular carcinoma (HCC)) that are commonly observed among individuals with multiple metabolic derangements, notably including visceral obesity, IR and T2D. Hepatitis C virus (HCV) infection is also often associated with both hepatic steatosis and features of a specific HCV-associated dysmetabolic syndrome. In recent years, the key role of the steatotic liver in the development of IR and T2D has been increasingly recognized. Thus, in this comprehensive review we summarize the rapidly expanding body of evidence that links T2D with NAFLD and HCV infection. For each of these two liver diseases with systemic manifestations, we discuss the epidemiological burden, the pathophysiologic mechanisms and the clinical implications. To date, substantial evidence suggests that NAFLD and HCV play a key role in T2D development and that the interaction of T2D with liver disease may result in a "vicious circle", eventually leading to an increased risk of all-cause mortality and liver-related and cardiovascular complications. Preliminary evidence also suggests that improvement of NAFLD is associated with a decreased incidence of T2D. Similarly, the prevention of T2D following HCV eradication in the era of direct-acting antiviral agents is a biologically plausible result. However, additional studies are required for further clarification of mechanisms involved.