Virologic, Clinical, and Immune Response Outcomes of Patients With Hepatitis C Virus-Associated Cryoglobulinemia Treated With Direct-Acting Antivirals

Imprinted immune abnormalities in liver transplant patients cured of hepatitis C with antiviral drugs

Chronic HCV infection induces interferon and dysregulates immune responses through inflammation and chronic antigenic stimulation. Antiviral drugs can cure HCV, providing a unique opportunity to examine the immunological restoration that does and does not occur when a chronic viral infection is eradicated. We quantified blood cytokines levels and used mass cytometry to immunophenotype peripheral blood mononuclear cells before and after HCV cure in 2 groups of patients and controls. At baseline, serum interferon α and soluble CD163 (a macrophage product) were elevated in both liver transplant and nonliver transplant patients compared to controls; the frequencies of several peripheral blood mononuclear cell populations differed from controls; and programmed death protein 1-positivity was increased in nearly all T cell subsets. Many abnormalities persisted after HCV cure, including elevated programmed death protein 1 expression on CD4 naïve and central memory T cells, elevated soluble CD163, and expansion of the plasmablast/plasma cell compartment. Several myeloid-lineage subsets, including Ag-presenting dendritic cells, remained dysregulated. In mechanistic studies, interferon α treatment increased programmed death protein 1 on human T cells and increased T cell receptor signaling. The data identify immunological abnormalities that persist after curative HCV treatment. Before cure, high levels of interferon α may stimulate programmed death protein 1 expression on human T cells, causing persistent functional changes.

Hepatitis C Virus Clearance and Diffusing Capacity for Carbon Monoxide in Women With and Without Human Immunodeficiency Virus

Hepatitis C virus (HCV) infection is associated with extrahepatic effects, including reduced diffusing capacity of the lungs. It is unknown whether clearance of HCV infection is associated with improved diffusing capacity. In this sample of women with and without human immunodeficiency virus, there was no association between HCV clearance and diffusing capacity.

Chronic Hepatitis C Virus Infection, Extrahepatic Disease and the Impact of New Direct-Acting Antivirals

Chronic hepatitis C virus infection is an important cause of liver cirrhosis, hepatocellular carcinoma and death. Furthermore, it is estimated that about 40-70% of patients develop non-hepatic alterations in the course of chronic infection. Such manifestations can be immune-related conditions, lymphoproliferative disorders and metabolic alterations with serious adverse events in the short and long term. The introduction of new Direct-Acting Antivirals has shown promising results, with current evidence indicating an improvement and remission of these conditions after a sustained virological response.

Extrahepatic manifestations of HCV where do we stand?

Hepatitis C virus (HCV) infection has been associated as up 40-70% of patients with extrahepatic manifestations (EHM) and 36 different syndromes. These could be attributed to the fact that HCV is lymphotropic, particularly B lymphotropic, and not merely hepatotropic, and could trigger immunological alterations indirectly by exerting a chronic stimulus on the immune system with production of immunoglobulins having rheumatoid activity forming immune complexes and production of cryoglobulins. Cryoglobulinemoa plays a pivotal role in producing most EHM of HCV such as vasculitis, glomerulonephritis, arthritis and neuropathies. Less frequently; while less frequently, the direct viral cytopathic effect could lead to EHMs independent of cryoglobulinemia. The mainstay of treatment of EMH has been antivirals, since interferon era to direct-acting drugs era, with no differences between the two eras, despite the better virological response. Longer evaluation of virological response and clinical investigation with longer follow-ups are necessary.

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.

Management of Hepatitis C Virus and Hepatitis B Virus Infection in the Setting of Kidney Disease

Treatment of chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infection poses unique challenges in patients with kidney disease. Direct-acting antivirals have been a major breakthrough in eradicating HCV infection, and several pangenotypic regimens are available for patients with chronic kidney disease or end-stage kidney disease requiring dialysis with high cure rates and no need for dose adjustment. Direct-acting antiviral therapy alone can treat HCV-associated cryoglobulinemic glomerulonephritis; concurrent antiviral and immunosuppressive therapy is needed for cases of severe, organ-threatening manifestations of cryoglobulinemia. Immunosuppression may be needed for HBV-associated kidney disease (polyarteritis nodosa or membranous nephropathy) when there is evidence of severe immune-mediated injury while weighing the risk of potential viral activation. Most HBV antiviral agents need to be dose-adjusted in patients with chronic kidney disease or end-stage kidney disease requiring dialysis, and drug-drug interactions need to be carefully evaluated in patients with kidney transplants. Considerations for accepting HCV- and HBV-infected donors for kidney transplantation are discussed.

Impact of treatment with direct-acting antivirals on inflammatory markers and autoantibodies in HIV/HCV co-infected individuals

HCV infection could have extrahepatic manifestations due to an aberrant immune response. HCV/HIV co-infection increases such persistent immune activation. Aim of the present study is to describe the evolution of inflammatory markers used in clinical practice, mixed cryoglobulinemia (MC) and autoantibody reactivity in co-infected individuals who achieved sustained virological response (SVR) after DAA treatment. This prospective, observational study included all HIV/HCV co-infected subjects who started any DAA regimen from 2015 to 2020. Samples for laboratory measurements (ferritin, C reactive protein, C3 and C4 fractions, rheumatoid factor, MC, anti-thyroglobulin Ab, anti-thyroid peroxidase Ab, ANCA, ASMA, anti-LKM, anti-DNA, AMA, ANA, T CD4+ and CD8+ cell count, and CD4/CD8 ratio) were collected at baseline, after 4 weeks, at end of treatment, and at SVR12. The analysis included 129 individuals: 51.9% with a F0-F3 fibrosis and 48.1% with liver cirrhosis. Cryocrit, C3 fraction, and rheumatoid factor significantly improved at week 4; ferritin, anti-thyroglobulin Ab, and C4 fraction at EOT; total leukocytes count at SVR12. MC positivity decreased from 72.8% to 35.8% (p < .001). T CD4+ cell slightly increased at SVR12, but with an increase also in CD8+ resulting in stable CD4/CD8 ratio. Autoantibody reactivity did not change significantly. ANA rods and rings positivity increased from 14.8% to 28.6% (p = .099): they were observed in three subjects without exposure to RBV. DAA therapy may lead to improvement in inflammatory markers and MC clearance but without significant changes in autoantibodies reactivity and CD4/CD8 ratio over a follow up of 12 weeks.

Biologic therapy in large and small vessels vasculitis, and Behçet's disease: Evidence- and practice-based guidance

OBJECTIVE

Vasculitis are a very heterogenous group of systemic autoimmune diseases, affecting large vessels (LVV), small vessels or presenting as a multisystemic variable vessel vasculitis. We aimed to define evidence and practice-based recommendations for the use of biologics in large and small vessels vasculitis, and Behçet's disease (BD).

METHODS

Recommendations were made by an independent expert panel, following a comprehensive literature review and two consensus rounds. The panel included 17 internal medicine experts with recognized practice on autoimmune diseases management. The literature review was systematic from 2014 until 2019 and later updated by cross-reference checking and experts' input until 2022. Preliminary recommendations were drafted by working groups for each disease and voted in two rounds, in June and September 2021. Recommendations with at least 75% agreement were approved.

RESULTS

A total of 32 final recommendations (10 for LVV treatment, 7 for small vessels vasculitis and 15 for BD) were approved by the experts and several biologic drugs were considered with different supporting evidence. Among LVV treatment options, tocilizumab presents the higher level of supporting evidence. Rituximab is recommended for treatment of severe/refractory cryoglobulinemic vasculitis. Infliximab and adalimumab are most recommended in treatment of severe/refractory BD manifestations. Other biologic drugs can be considered is specific presentations.

CONCLUSION

These evidence and practice-based recommendations are a contribute to treatment decision and may, ultimately, improve the outcome of patients living with these conditions.

Viral Glomerulopathy

Background

The association between viral infections and glomerular diseases, commonly known as "viral glomerulopathies," has been described in various clinical scenarios for decades. Despite advancements in diagnostic tools, it remains challenging to establish a causative link fully.

Summary

Data from mouse models have substantiated clinical observations and implicate direct viral infection in the pathogenesis of viral glomerulopathy, particularly in human immunodeficiency virus-associated nephropathy. In addition to the traditional concept of direct viral effects on kidneys, other factors such as APOL1 risk alleles can further modify the clinical outcomes or presentations of different viral glomerulopathies. Newly developed antiviral drugs are now applicable to a wider range of patients with lower kidney function and fewer side effects.

Key Message

Efforts focusing on vaccines and antiviral treatments have significantly reduced the incidence of viral glomerulopathies. However, the most recent pandemic caused by severe acute respiratory syndrome coronavirus 2 infection complicated by COVID-associated nephropathy illustrates our susceptibility to novel viruses. Ongoing research is pivotal to deciphering the mechanisms behind viral glomerulopathies and discovering therapeutics in a collaborative approach.

A prospective study of direct-acting antiviral effectiveness and relapse risk in HCV cryoglobulinemic vasculitis by the Italian PITER cohort

BACKGROUND AND AIMS

Mixed cryoglobulinemia is the most common HCV extrahepatic manifestation. We aimed to prospectively evaluate the cryoglobulinemic vasculitis (CV) clinical profile after a sustained virologic response (SVR) over a medium-term to long-term period.

APPROACH AND RESULTS

Direct-acting antiviral-treated cryoglobulinemic patients, consecutively enrolled in the multicentric Italian Platform for the Study of Viral Hepatitis Therapy cohort, were prospectively evaluated. Cumulative incidence Kaplan-Meier curves were reported for response, clinical deterioration, relapse and relapse-free survival rates. Cox regression analysis evaluated factors associated with different outcomes. A clinical response was reported in at least one follow-up point for 373 of 423 (88%) patients with CV who achieved SVR. Clinical response increased over time with a 76% improvement rate at month 12 after the end of treatment. A full complete response (FCR) was reached by 164 (38.8%) patients in at least one follow-up point. CV clinical response fluctuated, with some deterioration of the initial response in 49.6% of patients (median time of deterioration, 19 months). In patients who achieved FCR and had an available follow-up (137 patients) a relapse was observed in 13% and it was transient in 66.7% of patients. The rate of patients without any deterioration was 58% and 41% at 12 and 24 months, respectively. After achieving SVR, a clinical nonresponse was associated with older age and renal involvement; a clinical deterioration/relapse was associated with high pretreatment rheumatoid factor values, and FCR was inversely associated with age, neuropathy, and high cryocrit levels.

CONCLUSION

In patients with CV, HCV eradication may not correspond to a persistent clinical improvement, and clinical response may fluctuate. This implies an attentive approach to post-SVR evaluation through prognostic factors and tailored treatment.

Transient elastography score is elevated during rheumatoid factor-positive chronic hepatitis C virus infection and rheumatoid factor decline is highly variable over the course of direct-acting antiviral therapy

Background

Elevated rheumatoid factor (RF) levels and systemic immune activation are highly prevalent during chronic hepatitis C virus (HCV) infection. Direct-acting antiviral (DAA) therapy has been associated with normalization of various soluble immune activation parameters. Whether the RF levels relate to soluble immune activation markers during chronic HCV infection, and over what time frame RF levels normalize during and after DAA treatment is unknown and was investigated here.

Methods

In a longitudinal study, plasma and serum was obtained from HCV infected RF positive (RF+) and RF negative (RF-) participants. The levels of RF, HCV RNA and soluble markers of inflammation were determined before (week 0), during (weeks 4, 8 and 12) and after (week 24) treatment with HCV DAA therapy. In a subset of RF+ participants, the analysis was extended to over 70 weeks after therapy initiation. Hepatic and other clinical parameters were determined at baseline (week 0) in all participants.

Results

Before therapy, transient elastography (TE) score was greater in RF+ compared to RF- HCV infected participants, while the systemic levels of soluble inflammatory markers were comparable. Following DAA therapy initiation, HCV RNA levels became undetectable within 4 weeks in both the RF+ and RF- groups. RF levels declined in the first 6 months in most RF+ persons but most commonly remained positive. The levels of some soluble inflammatory markers declined, mainly within 4 weeks of DAA therapy start, in both the RF+ and RF- groups. The baseline (week 0) TE score correlated with RF levels before, during and after DAA therapy, while plasma IL-18 levels correlated with RF level after DAA therapy.

Conclusion

During chronic HCV infection, TE score is elevated in RF+ HCV infected individuals and factors other than HCV viremia (including liver stiffness or fibrosis and select markers of inflammation) likely contribute to persistence of RF after treatment of HCV with DAA.

Prevalence and Outcome of Serum Autoantibodies in Chronic Hepatitis C Patients Undergoing Direct-Acting Antiviral Treatment

Background

Chronic immune stimulation by hepatitis C virus (HCV) may cause occurrence of several autoantibodies in infected patients, with or without features of clinically overt autoimmune diseases. The recent introduction of direct-acting antivirals (DAAs) has dramatically changed the natural history of chronic HCV infection. The aim of this study was to assess the effects of DAA therapy on serum autoantibodies in chronic hepatitis C (CHC) patients.

Methods

The medical records of 113 CHC patients were reviewed to assess autoantibody behavior following DAA-directed HCV eradication. Statistical analysis was performed to assess correlations between DAA treatment and autoantibody titers, HCV genotypes, and viral loads.

Results

Anti-nuclear (ANA), anti-smooth muscle cell (ASMA) and anti-mitochondrial (AMA) antibody testing was available in 77 patients; 31 out of 77 patients (40%) had one or more serum autoantibodies prior to treatment. Measurement of autoantibody titers before and after HCV eradication was performed in 20 of 31 patients. DAA treatment significantly affected ANA and ASMA titers, leading to disappearance or reduction of autoantibody titers; conversely, AMA were not influenced by DAA treatment. No correlations were observed between autoantibody specificity and both HCV genotypes and viral loads at baseline. Likewise, serum autoantibody titers were independent of HCV genotypes.

Conclusions

DAA-directed HCV clearance may interrupt chronic immune stimulation by removing the drive for autoantibody induction. The isolated persistence of autoantibodies in the small fraction of patients who did not show clearance following DAA treatment may require long-term vigilance.

Evolution of Cryoglobulinemia in Direct-Acting Antiviral-Treated Asian Hepatitis C Patients With Sustained Virological Responses: A 4-Year Prospective Cohort Study

Background

How cryoglobulinemia evolves after sustained virological response (SVR) following direct-acting antiviral (DAA) treatment in Asian hepatitis C virus (HCV)-infected patients remains elusive.

Methods

A prospective cohort study was conducted in 422 Taiwanese patients (358 completed DAA therapy and 353 experienced SVRs). Serum cryoglobulins were surveyed at baseline and every 3-6 months posttherapy.

Results

Of 422, 227 (53.8%) had cryoglobulinemia, 8 (1.89%) had cryoglobulinemic vasculitis. Of 227, 54 (23.8%), 57 (25.1%) and 116 (51.1%) had 1, 2 and 3 cryoglobulins, respectively; those with 3 cryoglobulins had the highest alanine aminotransferase, immunoglobulin G (IgG) and fibrosis-4 index. During a 4-year follow-up, among SVR patients, cryoglobulinemia rates decreased from 56.4% to 15.4%, single cryoglobulin rates increased (21.6% to 63.9%) and 3 cryoglobulin rates decreased (55.7% to 11.1%). Compared with baseline values, among SVR patients with baseline cryoglobulinemia, complement component 4 levels increased, and IgG and IgM levels decreased until 48 weeks posttherapy for those without posttherapy cryoglobulinemia. All 8 cryoglobulinemic vasculitis patients exhibited SVRs; 5 (62.5%) achieved complete clinical response 12 weeks posttherapy, of whom, 2 (40%) experienced clinical relapse 24~48 weeks posttherapy. Baseline IgM levels were associated with posttherapy cryoglobulinemia in SVR patients (cut-off values at 12, 24, 48 weeks and 4 years posttherapy: 130, 105, 118 and 168 mg/dL, respectively).

Conclusions

Among DAA-treated SVR patients, in 4 years, cryoglobulinemia rates decreased from 56.4% to 15.4%, multiple cryoglobulin rates decreased, cryoglobulinemia signals reversed, 62.5% of cryoglobulinemic vasculitis patients achieved complete clinical response (40% had relapse), and baseline IgM levels indicated posttherapy cryoglobulinemia.

The wide spectrum of cryoglobulinemic vasculitis and an overview of therapeutic advancements

Immunoglobulins that reversibly precipitate at temperatures below 37 °C are called cryoglobulins (CGs). Cryoglobulinemia often manifests as cryoglobulinemic vasculitis (CV), whose symptoms range in severity from purpuric eruptions to life-threatening features. The majority of CV patients are infected with hepatitis C virus (HCV), whereas lymphoproliferative disorders or connective tissue diseases (CTD) are commonly diagnosed among patients with CV of non-infectious origin. In the absence of detectable associated disease, cryoglobulinemia is classified as “essential” (EMC). All HCV-positive CV patients should be given direct-acting antiviral agents (DAAs) that are consistently able to induce a sustained virologic response (SVR). Glucocorticoids (GCs) can mitigate CV-associated vasculitis, but they have no role as maintenance therapy. Cyclophosphamide restrains the hyperactive phase(s) of the disease and the post-apheresis rebound of newly synthesized CGs. Its use has been largely replaced by rituximab (RTX) in patients unresponsive to DAAs, patients progressing to B-cell non-Hodgkin lymphoma (B-NHL) and patients in whom CV persists or reappears after clearance of HCV. Therapeutic apheresis is an emergency treatment for CV patients with hyperviscosity syndrome. HCV-positive CV patients are at an increased risk of developing NHL, but the achievement of SVR can effectively prevent HCV-related NHL or induce the remission of an already established lymphoma, even without chemotherapy. The treatment of patients with IgM or IgG monoclonal cryoglobulins and an underlying immunoproliferative disorder is based on the regimens adopted for patients with the same B-cell malignancies but without circulating CGs. For patients with CTD, GCs plus alkylating agents or RTX are similarly effective as first-line therapy and in the relapse/refractory setting. In patients with EMC, treatment should consist of GCs plus RTX, with the dose of GCs tapered as soon as possible to reduce the risk of infectious complications.

Therapy of Chronic Viral Hepatitis: The Light at the End of the Tunnel?

Chronic viral hepatitis determines significant morbidity and mortality globally and is caused by three main etiological actors (Hepatitis B Virus, Hepatitis C Virus, and Hepatitis D Virus) with different replicative cycles and biological behaviors. Thus, therapies change according to the different characteristics of the viruses. In chronic hepatitis B, long term suppressive treatments with nucleoside/nucleotide analogues have had a dramatic impact on the evolution of liver disease and liver-related complications. However, a conclusive clearance of the virus is difficult to obtain; new strategies that are able to eradicate the infection are currently objects of research. The therapy for Hepatitis D Virus infection is challenging due to the unique virology of the virus, which uses the synthetic machinery of the infected hepatocyte for its own replication and cannot be targeted by conventional antivirals that are active against virus-coded proteins. Recently introduced antivirals, such as bulevertide and lonafarnib, display definite but only partial efficacy in reducing serum HDV-RNA. However, in combination with pegylated interferon, they provide a synergistic therapeutic effect and appear to represent the current best therapy for HDV-positive patients. With the advent of Direct Acting Antiviral Agents (DAAs), a dramatic breakthrough has occurred in the therapeutic scenario of chronic hepatitis C. Cure of HCV infection is achieved in more than 95% of treated patients, irrespective of their baseline liver fibrosis status. Potentially, the goal of global HCV elimination by 2030 as endorsed by the World Health Organization can be obtained if more global subsidised supplies of DAAs are provided.

Cryoglobulinemia

Cryoglobulins are immunoglobulins that precipitate in vitro at temperatures below 37 ̊C. Cryoglobulin-associated disease is heterogeneous, as not all patients present with it, includes various syndromic presentations (vasculitis is the most common, hyperviscosity syndrome is more exceptional), and can be associated with acute clinical pictures with high mortality. Until the appearance of specific antiviral treatments, the main aetiology has been chronic HCV infection, and currently it is mainly associated with systemic autoimmune diseases, malignant neoplasms and cases with no identified aetiology (essential cryoglobulinemia). Treatment should be modulated according to the predominant etiopathogenesis (vasculitis or hyperviscosity), the severity of internal organ involvement and, especially, the associated underlying disease. Due to the complex aetiological, clinical and pathological scenario of cryoglobulinaemia, early recognition of the most common clinical presentations, a comprehensive clinical assessment of the different organs that may be affected, and multidisciplinary work led by a unit specialised in systemic autoimmune diseases is essential.

Persistence of Cryoglobulinemic Vasculitis after DAA Induced HCV Cure

Treatment with a direct acting antiviral (DAA) has revolutionized HCV therapy, as more than 95% of patients achieve a sustained virological response (SVR). Cryoglobulinemic vasculitis (CryoVas), however, can persist and recur after the HCV cure. In this systematic review, we include data from 19 studies that provided information on the persistence and recurrence of CryoVas after the HCV cure with DAAs. A complete clinical response (CR) was reported in 63.7% to 90.2% of the DAA-treated patients after achieving SVR. Relapse of CryoVas symptoms was reported in 4% to 18% of the patients. Neuropathy, nephropathy, and dermatological complications were the most common manifestations of CryoVas. B-cell clones persisted in 31–40% of the patients and could contribute to CryoVas relapse. INFL3-rs12979860, ARNTL-rs648122, RETN-rs1423096, and SERPINE1-rs6976053 were associated with a higher incidence of persistence and recurrence of CryoVas. Prospective multicenter studies with diverse patient populations are needed to validate these findings for the timely and effective management of this challenging condition.

Impact of direct acting antivirals (DAA) on neurologic disorders in chronic hepatitis C

INTRODUCTION

Neurologic and neuropsychiatric manifestations sometimes provide the first evidence of an unknown HCV infection. These conditions develop with a variable ranging of morbidity, including: "brain fog," fatigue, subtle cognitive and attention impairment, but also with more severe complications or acute presentation, like encephalomyelitis, encephalopathy, stroke and peripheral nerves involvement.

EVIDENCE ACQUISITION

We performed a systematic literature search on PubMed, Cochrane Library and Web of Science databases for articles only in English language, that assessed the relationship between "DAA treatment and neurologic disorders" and after the attainment of SVR in full reports of cases that received the DAA schedule from January 2015 to December 2019. The following terms were used: "chronic Hepatitis C," "HCV," "DAA," "direct-acting antiviral," "SVR," "sustained virologic response," peripheral neuropathy" and "neurologic diseases or disorders."

EVIDENCE SYNTHESIS

HCV infection does not only involve the liver, causing cirrhosis and hepatocellular carcinoma (HCC), but also induces extrahepatic manifestations (EHM), mainly due to a complex immune disease, that damage small and medium vessels, called "mixed cryoglobulinemic vasculitis" (MCV). This kind of mechanism generates most of the HCV-induced neurological damages. Since 2015, the availability of direct-acting antiviral (DAA) oral molecules interfering with HCV replication has completely revolutionized therapeutic options and the target population, which now includes patients aged 12 to 80 years and with advanced liver disease. Relevant was the highlighted DAA effectiveness by achievement of a sustained virologic response (SVR) in about 95% of cases, showing a great tolerability.

CONCLUSIONS

This favorable effect has arisen in a wide category of patients infected by HCV, including subjects with cirrhosis and complications and/or with EHM, who showed a significant improvement of their symptoms and the disease regression. In this concise review, we examine the clinical outcomes after the introduction of the DAA for the treatment of chronic hepatitis C (CHC), focusing on the neurologic disorders and concluding that there is a strong amelioration of neurologic conditions in several cases, particularly, after attaining the viral eradication with a favorable course in most treated cases.

Hepatitis C virus-related vasculitis

Cryoglobulinemic vasculitis (CryoVas) is a small-to-medium vessel systemic vasculitis caused by the deposition of mixed cryoglobulins and immune complexes. Clinical spectrum of CryoVas ranges from mild symptoms to vasculitis involving multiple organs that may progress to more life-threatening ilness. Hepatitis C virus (HCV) chronic infection is the most frequent condition to be assessed in patients with CryoVas. The mortality rate among patients with HCV-associated CryoVas is 3× that of the general population, with a 63% 10-year survival rate. The recent advent of interferon-free direct-acting antivirals (DAAs), which have the potential to induce sustained virological response rates greater than 95%, has dramatically changed the management of chronic HCV infection and HCV-related CryoVas. B-cell depleting strategies, mainly with rituximab, are the main therapeutic option in severe and refractory cases of HCV-associated CryoVas. Despite the progress in the last years on the management of chronic HCV infection, there are still unmet needs regarding therapeutic management of severe and refractory HCV-associated CryoVas.

Predictors of long-term cryoglobulinemic vasculitis outcomes after HCV eradication with direct-acting antivirals in the real-life

Cryoglobulinemic vasculitis (CV) is the most frequent extrahepatic manifestation during HCV-chronic infection. An effective Direct Acting Antiviral-treatment leads to CV clinical response in the majority of CV-patients although symptoms may persist/recur despite a sustained virological response. At present, no standardized clinical predictive factors for disease maintenance/recurrence were proposed, as emerged from a complete literature review we performed and reported. Here we provided a detailed descriptive analysis of a wide population of CV patients treated with DAA-based regimes and followed-up after therapy completion for longer than 72 weeks, in order to identify clinical or laboratory predictors of disease outcome and to optimize the patient management. Together with some baseline symptoms (neuropathy, weakness and sicca syndrome), two newly created scores, CV- and Global Severity Index, emerged as reliable and standardized tools to predict CV clinical response before initiating an antiviral therapy. In addition to predictive parameters previously proposed in the world literature, these novel Indexes could fill an unmet gap in the clinical management of the complex HCV-related CV.

Changes in clinical scenarios, management, and perspectives of patients with chronic hepatitis C after viral clearance by direct-acting antivirals

INTRODUCTION

Hepatitis C virus (HCV) causes a systemic infection inducing hepatic and extrahepatic diseases. These latter involve cardiovascular system, kidney, brain, endocrine, glucose, and lipid metabolism, and the immune system. HCV infection is associated with an increased risk of morbidity and mortality for both hepatic and extrahepatic events. Direct-acting antivirals (DAA), introduced in the most recent years for HCV treatment, are effective in up to 99% of cases and have changed the clinical scenarios and management of these patients.

AREAS COVERED

The literature on the impact of HCV clearance by DAA on both hepatic and extrahepatic disease outcomes has been analyzed and discussed in this review in order to summarize the full therapeutic potential and its weaknesses.

EXPERT OPINION

Patients achieving HCV clearance have improved hepatic and extrahepatic diseases, quality of life and survival. They have lower incidence of cardiovascular disease, type 2 diabetes, kidney damage, and immuno-mediated manifestations. However, the improvements are related to the degree of pre-treatment organ damage. Therefore, a significant percentage of patients with advanced disease remains at risk of morbidity and mortality and must be monitored in the post-treatment. In addition, data emphasize the importance of starting treatment during the early stages of HCV infection.

Progress in hepatitis C virus management in chronic kidney disease

PURPOSE OF REVIEW

The current review highlights advances in the use of direct-acting antiviral (DAA) agents in the treatment of hepatitis C virus (HCV) in chronic kidney disease (CKD) stages G4-5, end-stage renal disease, and kidney transplantation. The use of DAA to facilitate kidney transplantation of HCV negative recipients with kidneys from HCV-infected donors and in the management of HCV-related cryoglobulinemia are also reviewed.

RECENT FINDINGS

DAA treatment results in rates of viral clearance (sustained virological response or SVR) of 90-100% in all studied CKD populations, comparable to SVR rates in the general population. DAA treatment allows safe and effective transplantation of HCV viremic kidneys into uninfected recipients.

SUMMARY

The high SVR results achieved with DAA allow successful treatment of previously under-treated CKD populations, and encouraged innovative interventions such as the use of HCV-infected donor kidneys to uninfected kidney transplant recipients.

Impact of DAA-Based Regimens on HCV-Related Extra-Hepatic Damage: A Narrative Review

Two-third of patients with chronic hepatitis C show extrahepatic manifestations due to HCV infection of B lymphocytes, such as mixed cryoglobulinemia and non-Hodgkin B-cell lymphoma, or develop a chronic inflammatory status that may favor the development of adverse cardiovascular events, kidney diseases or metabolic abnormalities.DAAs treatments induce HCV eradication in 95% of treated patients, which also improves the clinical course of extrahepatic manifestations, but with some limitations. After HCV eradication a good compensation of T2DM has been observed, but doubts persist about the possibility of obtaining a stable reduction in fasting glucose and HbA1c levels.Chronic HCV infection is associated with low total and LDL cholesterol serum levels, which however increase significantly after HCV elimination, possibly due to the disruption of HCV/lipid metabolism interaction. Despite this adverse effect, HCV eradication exerts a favorable action on cardiovascular system, possibly by eliminating numerous other harmful effects exerted by HCV on this system.DAA treatment is also indicated for the treatment of patients with mixed cryoglobulinemia syndrome, since HCV eradication results in symptom reduction and, in particular, is effective in cryoglobulinemic vasculitis. Furthermore, HCV eradication exerts a favorable action on HCV-related lymphoproliferative disorders, with frequent remission or reduction of clinical manifestations.There is also evidence that HCV clearance may improve impaired renal functions, but same conflicting data persist on the effect of some DAAs on eGFR.

Impact of direct acting antivirals on hepatitis c virus-related cryoglobulinemic syndrome

INTRODUCTION

Mixed cryoglobulinemia (MC) is a B-cell lymphoproliferative disorder largely attributable to HCV infection. MC clinical manifestations are determined by systemic vasculitis of low/medium sized vessels (mixed cryoglobulinemia syndrome or cryoglobulinemic vasculitis and CV) caused by the deposition of cryoglobulins in blood vessels.

EVIDENCE ACQUISITION

A systematic review was performed via the Medline and Scopus databases to evaluate studies concerning CV treatment with new direct antiviral agents (DAAs) and their effect on the syndrome.

EVIDENCE SYNTHESIS

The introduction of Interferon-free protocols has led to more evident positive effects than those observed in the treatment of C hepatitis/cirrhosis. In fact, IFN-free, DAA-based therapy minimised side effects permitting the treatment of previously contraindicated patients and led to a particularly high SVR rate and to a clinical/immunological response in the majority of patients, even if at different levels in different patients, from restitutio ad integrum to partial response. In view of the clearly positive evolution in CV management, the persistence of CV manifestations, in partial or non-responders continues to pose problems in the clinical approach to patients who represent a new condition that is still not completely known.

CONCLUSIONS

Results of DAAs-based therapy strongly confirm the use of anti-HCV therapy as the first-line therapeutic option in CV patients. However, growing evidence of a possible persistence or late relapse of CV suggests the need for longer/more accurate post-DAAs follow-ups as well as biomarkers that are capable of predicting the risk of clinical relapse/persistence to allow for the design of rational post-HCV eradication clinical flow-charts.

[Chronic kidney injury in patients with liver diseases - Reappraising pathophysiology and treatment options]

Acute and chronic kidney disease concurs commonly with liver disease and is associated with a wide array of complications including dialysis dependency and increased mortality. Patients with liver disease or liver cirrhosis show a higher prevalence of chronic kidney disease. This is attributed to concomitant comorbidities, such as metabolic syndrome, chronic inflammation, hypercoagulability, hyperfibrinolysis, diabetes mellitus and dyslipidaemias. But chronic progressive kidney disease is not always due to hepatorenal syndrome. Beyond that, other diseases or disease entities should be considered. Among them are diabetic nephropathy, secondary IgA nephropathy, hepatitis C -associated membranoproliferative Glomerulonephritis (MPGN) and hepatitis B-associated membranous nephropathy.Coexisting diseases, similar underlying pathophysiologic mechanisms, or simultaneously concurring pathophysiological processes and overlapping clinical manifestations, impede the etiologic diagnosis and corresponding treatment of chronic kidney disease in the setting of chronic liver disease. In this review, we focus on common and rare pathologies, which can lead to chronic kidney disease in this particular patient group and try to summarize the most recent therapeutic modalities.

Antibody Responses in Hepatitis C Infection

Antibody responses in hepatitis C virus (HCV) have been a rather mysterious research topic for many investigators working in the field. Chronic HCV infection is often associated with dysregulation of immune functions particularly in B cells, leading to abnormal lymphoproliferation or the production of autoantibodies that exacerbate inflammation and extrahepatic diseases. When considering the antiviral function of antibody, it was difficult to endorse its role in HCV protection, whereas T-cell response has been shown unequivocally critical for natural recovery. Recent breakthroughs in the study of HCV and antigen-specific antibody responses provide important insights into viral vulnerability to antibodies and the immunogenetic and structural properties of the neutralizing antibodies. The new knowledge reinvigorates HCV vaccine research by illuminating a new path for the rational design of vaccine antigens to elicit broadly neutralizing antibodies for protection.

Hepatitis C virus-related cryoglobulinemic vasculitis

INTRODUCTION

Hepatitis C virus (HCV) infection affects about 170 million people worldwide. HCV is responsible for both hepatitis and extra-hepatic manifestations. Chronic infection has been shown to develop in about 70% of cases, and it can progress to cirrhosis or hepatocellular carcinoma. Ten percent of HCV patients may develop extra-hepatic manifestations, including mixed cryoglobulinemia (MC) and non-Hodgkin lymphomas (NHL). Cryoglobulinemic vasculitis (CV) varies, ranging from mild-moderate clinical symptoms (purpura on the legs, asthenia and arthralgias) and chronic hepatitis to severe symptoms (ulcers on the legs, peripheral neuropathy, glomerulonephritis, low-grade NHL to life threatening complications (rapid progressive glomerulonephritis, gastrointestinal vasculitis, acute hyper-viscosity).

EVIDENCE ACQUISITION

CV is associated with significant morbidity and mortality. Some studies have shown kidney involvement, cirrhosis, central nervous system involvement, and heart involvement as unfavorable prognostic factors. Many studies have demonstrated that, after antiviral therapy, CV can disappear along with HCV. After the introduction of the new direct antiviral agents (DAAs), the combination of pegylated interferon and ribavirin has been abandoned.

EVIDENCE SYNTHESIS

Several studies on new DAAs have reported remarkable 90% to 100% HCV eradication rates, regardless of genotype. Treatment with DAAs has comparable efficacy on viral eradication in CV patients but definite clinical improvements of vasculitis can be observed only in half the patients.

CONCLUSIONS

In patients with mild to moderate CV disease, DAAs therapy should be used as first line approach. In patients with severe vasculitis, DAAs therapy and a second-line treatment with RTX with or without aphaeresis are a required.

Interferon-Free Hepatitis C Virus Therapy

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease, with ∼71 million chronically infected individuals worldwide. Treatment of patients with HCV-related liver disease has advanced considerably thanks to the development of new direct-acting antiviral drugs that are now administered as highly potent, safe, and well-tolerated combinations with a high barrier to resistance. International organizations, such as the European Association for the Study of the Liver, the American Association for the Study of Liver Diseases jointly with the Infectious Diseases Society of America, or the World Health Organization have published detailed treatment guidelines. With these therapies becoming more and more widely available, elimination of hepatitis C as a public health threat by 2030 can now be envisaged in several countries. In other regions, better screening, diagnosis, and linkage to care will be necessary to achieve this ambitious goal.

Remission of long-term hepatic and renal disease induced by HCV after direct-acting antivirals therapy

In addition to liver disease, the hepatitis C virus (HCV) has been associated with autoimmune phenomena, such as mixed cryoglobulin and glomerulonephritis (GN). Until recently, both chronic hepatitis and HCV extra-hepatic manifestations were treated with peg-interferon plus ribavirin, however these drugs presented low efficacy and induced severe side effects. Nowadays, the HCV chronic hepatitis has been treated with direct acting antivirals (DAA), but studies on the DAA therapy for HCV-associated glomerulonephritis are scarce. Here, we describe two cases of HCV-associated glomerulonephritis that were treated with DAAs. In these two cases, previously experienced to peg-interferon plus ribavirin, the sofosbuvir plus simeprevir therapy was effective, without significant side effects, and interrupted the evolution of at least 20 years of both hepatic and renal diseases. These cases join the seven previously described cases that were treated with this DAAs association.

Hepatitis C in Chronic Kidney Disease: An Overview of the KDIGO Guideline

Hepatitis C virus (HCV) infection is a global health problem with significant health and economic burden, which can lead to chronic kidney disease (CKD) and affect multiple organ systems. In addition, prevalence of hepatitis C remains higher in patients with CKD, including those on chronic hemodialysis and in individuals with a kidney transplant than in the general population. There has been a dramatic shift in the management of hepatitis C since Kidney Disease: Improving Global Outcome (KDIGO) published its 2008 guideline for the prevention, diagnosis and management of hepatitis C in CKD. As a result, KDIGO published in 2018 an update to this guideline. In this narrative review, we present a synopsis of the guideline, including recommendations for screening and detection of HCV in CKD, treatment of HCV in patients with CKD, treatment of HCV before and after kidney transplantation, prevention of HCV transmission in hemodialysis units, and treatment of kidney disease related to HCV infection. We focus on the clinical aspects of using direct acting antivirals (DAAs) in patients with advanced CKD (G4 and G5), those on dialysis and kidney transplant recipients. We emphasize the importance of carefully managing drug-drug interactions between DAAs and immunosuppressive agents. We discuss timing of HCV treatment before vs. after kidney transplantation. Finally, we highlight areas of uncertainty where further research is needed before any definitive recommendations can be made.

Treatment of chronic hepatitis C-associated cryoglobulinemia vasculitis at the era of direct-acting antivirals

Hepatitis C virus (HCV) infection is responsible for both hepatic and extrahepatic manifestations. Before the era of direct-acting antivirals (DAA), cryoglobulinemia was related to HCV infection in 70-90% of cases. Observed in 30% to 40% of patients with hepatitis C, mixed cryoglobulinemia is mainly asymptomatic. Conversely, symptomatic cryoglobulinemia vasculitis (CV) can occur in 5-10% of patients with HCV-associated cryoglobulinemia. CV is a small-vessel systemic vasculitis, and organ damage results from circulation and precipitation of cryoglobulins and complement activation. A wide range of clinical symptoms can be observed during CV, and manifestations are potentially life-threatening. The most frequent manifestations occurring in CV are cutaneous, with recurrent purpura, articular with joint pains, neurologic with peripheric neuropathy, and renal with membranoproliferative glomerulonephritis. DAA have drastically changed chronic HCV therapy. DAA induce sustained virological response (SVR) rates greater than 95%, and also improve extrahepatic manifestations such as CV. We review recent studies investigating the clinical and immune effects of DAA therapy on HCV-CV.

Contribution of Hepatitis C Infection to a Large Cohort of Cryoglobulin-Positive Patients: Detection and Characteristics

Cryoglobulins (CGs) are cold precipitating immunoglobulins, and hepatitis C virus (HCV) infection is its most common cause. The purpose of the study was to determine the contribution of HCV in a large cohort of CG. Biological characteristics and specificity of CGs in HCV patients were compared to non-HCV subjects. Cryoglobulin analysis included isotype, clonality, concentration, and rheumatoid factor (RF) in cryoprecipitate and serum complement and RF. This study is an extension of the study carried out on a cohort of 13,439 patients tested for CGs from all medical units, in which 1,675/13,439 (12.5%) patients had a CG, and 680/1,675 (40.6%) had HCV serology or viral load determination (HCV RNA). Among these 680 CG patients tested for HCV, 325 of 680 (47.8%) HCV patients (272 HCV RNA⁺ and 45 HCV RNA⁻ patients) were compared to 355/680 (52.2%) non-HCV subjects. After a positive detection of CG, HCV status was determined only for 37.7% (256/680) of patients, allowing the diagnosis of a previously unknown HCV infection for 39.8% (102/256). Concentration of HCV RNA⁺ CGs (median = 80.5 mg/L) was significantly higher than that of HCV RNA⁻ CG (median = 50.5 mg/L, p = 0.001) and HCV⁻ CG (median = 32 mg/L, p < 0.0001). There was no difference of median CG concentration between HCV RNA⁻ patients and non-HCV subjects. Rheumatoid factor titer was significantly higher in type II CG compared to type III CG in HCV RNA⁺ patients (254 ± 720 vs. 15 ± 21 IU/mL, p < 0.0001) and non-HCV subjects (333 ± 968 vs. 16.8 ± 26 IU/mL, p = 0.0004). Complement functional activity CH50 was lower in HCV RNA⁺ patients (36 ± 24 U/mL) and in HCV RNA⁻ patients (32 ± 21 U/mL) than in non-HCV subjects (50 ± 25 U/mL, p = 0.001 and p = 0.004). In conclusion, HCV infection and treatment influence CG characteristics. It is essential, and far from always tested, to determine the HCV status of patients with mixed CG, and conversely to search for CG in patients with HCV infection.

Impact of Direct Acting Antiviral Agent Therapy upon Extrahepatic Manifestations of Hepatitis C Virus Infection

PURPOSE OF REVIEW

Direct acting antiviral agents (DAAs) have emerged as simple, short, safe, and effective treatments for chronic hepatitis C (CHC) infection. CHC is a systemic disease with frequent and multiple extrahepatic manifestations. The beneficial effects of DAA treatment regimens extend beyond improvement in liver-related outcomes to amelioration of extra hepatic manifestations and are likely to have economic implications. The purpose of this review is to evaluate the effect of DAAs on extra hepatic manifestations of CHC virus infection.

RECENT FINDINGS

Recent studies indicate that DAAs are associated with reduction in all-cause mortality, even in patients without significant hepatic fibrosis. They are also associated with reduction in incident cardiovascular disease and diabetes. DAAs are the mainstay of treatment in HCV-associated cryoglobulinemia and lymphoma. Successful HCV therapy with DAAs also improves patient-related outcomes such as health-related quality of life. DAAs improve extrahepatic manifestations of CHC virus infection. Future studies are needed to evaluate the long-term durability of treatment response and for accounting amelioration of extrahepatic manifestations into the cost effectiveness of DAA regimens.

Vasculitis

Vasculitis, characterized by inflammation and necrosis, manifests a wide spectrum of presentation by involving a vasculature of various sizes and locations. A definitive diagnosis of vasculitis invariably requires histologic confirmation since there are no diagnostic clinical, imaging, or laboratory findings. The most widely adopted vasculitis classification is the Chapel Hill Consensus Conference (CHCC) nomenclature of systemic vasculitis which integrated clinical symptoms, histopathologic features, and laboratory findings. This classification accounts for the size of the involved vessels. This chapter outlines the clinical and histologic features of the small-vessel vasculitis including the immune complex vasculitis and antineutrophil cytoplasmic antibody-associated vasculitis; medium-vessel vasculitis such as polyarteritis nodosa and Kawasaki disease; large-vessel vasculitis, namely, giant cell arteritis and Takayasu arteritis; variable-vessel vasculitis such as Behcet disease and Cogan syndrome; and vasculitis associated with systemic diseases including rheumatoid arthritis, lupus vasculitis, and sarcoid vasculitis. Vasculitis can also be secondary to drugs, infection, underlying systemic disease, or trauma. Therefore, a diagnosis of vasculitis cannot be based on histologic ground alone. Clinical pathologic correlation is necessary.

Direct-acting antiviral therapy improves kidney survival in hepatitis C virus-associated cryoglobulinaemia: the RENALCRYOGLOBULINEMIC study

Background

Direct-acting antiviral agents (DAAs) have shown high rates of sustained virological response in chronic hepatitis C virus (HCV) infection. However, the influence of DAAs on the course of kidney involvement in HCV-associated mixed cryoglobulinaemia (HCV-MC) has been little studied. The aim of this study was to analyse the effects of antiviral treatment on kidney prognosis and evolution in patients diagnosed with HCV-MC.

Methods

The RENALCRYOGLOBULINEMIC study is an observational multicentre cohort study of 139 patients with HCV-MC from 14 Spanish centres. Clinical and laboratory parameters were measured before and after antiviral treatment. Primary endpoints were kidney survival and mortality after HCV-MC diagnosis. Secondary endpoints were clinical, immunological and virological responses after antiviral treatment.

Results

Patients were divided into three groups based on the treatment received: treatment with DAAs (n = 100) treatment with interferon (IFN) and ribavirin (RBV) (n = 24) and no treatment (n = 15). Patients were followed up for a median duration of 138 months (interquartile range 70-251. DAA treatment reduced overall mortality {hazard ratio [HR] 0.12 [95% confidence interval (CI) 0.04-0.40]; P < 0.001} and improved kidney survival [HR 0.10 ( 95% CI 0.04-0.33); P < 0.001].

Conclusions

Results from the RENALCRYOGLOBULINEMIC study indicated that DAA treatment in patients with HCV-MC improves kidney survival and reduces mortality.

Safety and efficacy of direct-acting antivirals for chronic hepatitis C in patients with chronic kidney disease

BACKGROUND

This is a real-world evidence study that aims to analyze the efficacy, tolerability and safety profile of paritaprevir/ombitasvir/ritonavir and dasabuvir, in patients with renal impairment.

METHODS

We conducted an observational prospective study, on 232 patients with chronic kidney disease, undergoing treatment with paritaprevir/ombitasvir/ritonavir and dasabuvir, for chronic hepatitis C infection - genotype 1b. Renal and liver function were assessed at the beginning of therapy, monthly during treatment and three months after therapy completion.

RESULTS

All patients achieved sustained virologic response. Common side effects were nausea, fatigue and headache. Close monitoring of tacrolimus blood levels and dose reduction was required in kidney transplant recipients.

CONCLUSIONS

HCV therapy in the setting of renal dysfunction has always been a challenging topic. Direct-acting antivirals have shown promising effects, demonstrating good tolerance and efficacy in patients with HCV infection and renal impairment. Sustained virologic response within our study population was 100%.

Expert opinion on managing chronic HCV in patients with mixed cryoglobulinaemia vasculitis

Mixed cryoglobulinaemia vasculitis (CryoVas) is a small-vessel systemic vasculitis caused by deposition of mixed cryoglobulins and is characterized by a wide range of clinical symptoms. HCV is the primary cause of CryoVas, which is associated with significant morbidity and mortality. The mortality rate among patients with HCV-associated CryoVas is 3× that of the general population, with a 63% 10-year survival rate. First-line treatment for CryoVas is anti-HCV therapy because viral clearance is associated with clinical improvement. The introduction of highly effective, interferon-free, direct-acting antiviral regimens provides additional treatment options for these patients. Here, we review recent studies investigating the effect of antiviral therapy on HCV-associated CryoVas and provide expert opinion for health-care professionals managing these patients.

Clinical outcome of HCV-associated cryoglobulinemic glomerulonephritis following treatment with direct acting antiviral agents: a case-based review

Newer treatment protocols involving direct-acting antiviral agents (DAAs) have been associated with high rates of sustained virologic response (SVR) and clinical remission in patients with hepatitis C virus (HCV) associated cryoglobulinemic vasculitis (HCV-CV), but clinical response in those with renal involvement is less clear. Our goal was to evaluate the clinical course following DAA therapy in one of the largest cohorts of patients with HCV-associated cryoglobulinemic glomerulonephritis (HCV-GN) reported to date. This is an observational study of patients with chronic HCV infection and circulating cryoglobulins (CC) treated with DAAs in our department from January 2015 to January 2019. We identified a total of 67 patients with HCV and CC out of which nine patients fulfilled the criteria of HCV-GN and had adequate clinical follow-up time. We describe a cohort of nine patients with a mean age of 57 years and known duration of HCV infection ranging 3-20 years (four with evidence of compensated cirrhosis). All patients received the ritonavir-boosted paritaprevir/ombitasvir/dasabuvir regimen for 12 weeks and achieved SVR without subsequent viral relapse. Following DAAs completion, one patient developed "new-onset" cryoglobulinemic glomerulonephritis, six showed either persistent or worsening glomerulonephritis, and only two patients had a complete clinical response (CCR). Of the six patients with either persistent or worsening CV, 67% received additional immunosuppressive (IS) therapy for uncontrolled CV. Of the two patients that had a CCR, one patient received prior IS therapy while the other one improved without any additional intervention. Newer HCV treatment protocols involving DAAs are highly successful in eradication of HCV infection; however, in our experience, DAA treatment alone is insufficient in improving the renal outcomes of patients with HCV-GN and additional IS therapies should be considered.

Treatment of hepatitis C virus infection in patients with mixed cryoglobulinemic syndrome and cryoglobulinemic glomerulonephritis

Cryoglobulinemia is a common extrahepatic manifestation of infection with hepatitis C virus (HCV). When signs and symptoms of systemic vasculitis or glomerulonephritis occur in the presence of circulating cryoglobulins, this syndrome is called "mixed cryoglobulinemia syndrome" (MCS). Historically, interferon-based therapies in HCV have been associated with lower rates of viral cure in patients with MCS than in the general HCV-infected population. The advent of direct-acting antiviral therapies have revolutionized the treatment of HCV, dramatically increasing rates of cure. Early studies of first-generation protease inhibitors (telaprevir and boceprevir) in combination with interferon and ribavirin demonstrated HCV cure rates of 67% and complete clinical response rates of vasculitis symptoms in 60% of patients with MCS; however, regimens were poorly tolerated by patients, 22% discontinued treatment early. More recently, all-oral, interferon-free regimens have become available and combination therapies are now being approved for patients with and without renal impairment. Patients with HCV-MCS achieved sustained virologic response in 297 out of 313 patients (95%) treated with direct-acting antiviral therapy, and 85% had a complete or partial clinical response of MCS symptoms. Current direct-acting antiviral therapies are well tolerated in patients with HCV-MCS and only 1.6% discontinued treatment early. Patients with cryoglobulinemic glomerulonephritis also had an excellent cure rate (94%). The majority improved; 17/52 (33%) experienced full remission and 15/52 (29%) experienced partial remission. There were no reports of worsening kidney function in patients treated with direct-acting antiviral therapies. Less than 5% of patients with HCV-MCS treated with IFN-free direct-acting antiviral therapy required immunosuppression. However, patients with severe vasculitis appear to still require concomitant immunosuppression.

Rheumatologic Diseases and the Liver

A variety of rheumatologic disorders may affect the liver. There is a significant epidemiologic, genetic, and immunologic overlap between immune-mediated rheumatologic disorders and autoimmune liver diseases. There is an increased frequency of autoimmune liver diseases, such as primary biliary cholangitis, autoimmune hepatitis, primary sclerosing cholangitis, or overlap syndrome, in patients with systemic lupus erythematosus, rheumatoid arthritis, Sjögren syndrome, systemic sclerosis, vasculitis, and other immune-related diseases. Non-immune-mediated rheumatologic diseases such as gouty arthritis may also have hepatic manifestations. Furthermore, medications used to treat rheumatologic diseases occasionally cause liver dysfunction. Conversely, primary immune-mediated and non-immune-mediated liver disorders may present with rheumatologic manifestations.

HCV-Associated Nephropathies in the Era of Direct Acting Antiviral Agents

Hepatitis C virus (HCV) infection is a systemic disorder that frequently associates with extrahepatic manifestations, including nephropathies. Cryoglobulinemia is a typical extrahepatic manifestation of HCV infection that often involves kidneys with a histological pattern of membranoproliferative glomerulonephritis. Other, less common renal diseases related to HCV infection include membranous nephropathy, focal segmental glomerulosclerosis, IgA nephropathy, fibrillary and immunotactoid glomerulopathy. Over the last decades, the advent of direct-acting antiviral therapies has revolutionized treatment of HCV infection, dramatically increasing the rates of viral clearance. In patients where antiviral therapy alone fails to induce renal disease remission add-on B-cell depleting agents represent an alternative to counteract the synthesis of pathogenic antibodies. Immunosuppressive therapies, such as steroids, alkylating agents, and plasma exchanges, may still represent an effective option to inhibit immune-complex driven inflammatory response, but the potentially associated increase of HCV replication and worsening of liver disease represent a serious limitation to their use.

Long-term Efficacy of Interferon-Free Antiviral Treatment Regimens in Patients With Hepatitis C Virus-Associated Cryoglobulinemia Vasculitis

BACKGROUND & AIMS

In small-size and short-term studies of hepatitis C virus-associated cryoglobulinemia vasculitis (HCV-CryoVas), patients had a higher rate of response and tolerance to direct-acting antiviral (DAA) agents than interferon-containing regimens. We collected follow-up data from a clinical trial to determine the long-term effectiveness and tolerance of all-oral, interferon-free DAA regimens in patients with CryoVas.

METHODS

We collected follow-up data from a prospective international multicenter cohort study of 148 patients with symptomatic HCV-CryoVas (53.7% with cirrhosis and 49.3% naive to treatment with DAAs). All patients received DAA (sofosbuvir plus daclatasvir, n = 53; sofosbuvir plus ribavirin, n = 51; sofosbuvir plus ledipasvir, n = 23; or sofosbuvir plus simeprevir, n = 18), for 12 or 24 weeks, from 2014 through 2017; the median follow-up time was 15.3 months. A complete clinical response was defined as improvement of all organs involved at baseline and the absence of clinical relapse; a partial response was defined as improvement in some but not all organs involved at baseline. The primary end point was clinical response of CryoVas symptoms at week 12 after stopping DAA therapy.

RESULTS

A complete response was reported for 106 patients (72.6%), a partial response for 33 patients (22.6%), and no response for 7 patients (4.8%). Cryoglobulins were no longer detected in blood samples from 53.1% of patients, and 97.2% of the patients had a sustained virologic response to therapy. Premature DAA withdrawal was reported for 4.1% of patients. Factors associated with no or partial response to therapy included a severe form of CryoVas (odds ratio, 0.33; 95% CI, 0.12-0.91; P = .03) and peripheral neuropathy (odds ratio, 0.31; 95% CI, 0.11-0.84; P = .02). After a median follow-up time of 15.3 months, 4 patients (2.8%) died. The CryoVas manifestation of purpura was cleared from 97.2% of patients, renal involvement from 91.5% of patients, arthralgia from 85.7% of patients, neuropathy from 77.1% of patients, and cryoglobulinemia from 52.2%.

CONCLUSIONS

In a long-term follow-up analysis of data from a clinical trial, we found that more than 95% of patients with HCV-CryoVas have a full or partial response of symptoms to different DAA treatment regimens. Fewer than 5% of patients stop therapy prematurely and less than 3% die. A severe form of CryoVas and peripheral neuropathy were associated with a lack of response of HCV-CryoVas to DAA therapy.

Binding of Free and Immune Complex-Associated Hepatitis C Virus to Erythrocytes Is Mediated by the Complement System

Erythrocytes bind circulating immune complexes (ICs) and facilitate IC clearance from the circulation. Chronic hepatitis C virus (HCV) infection is associated with IC-related disorders. In this study, we investigated the kinetics and mechanism of HCV and HCV-IC binding to and dissociation from erythrocytes. Cell culture-produced HCV was mixed with erythrocytes from healthy blood donors, and erythrocyte-associated virus particles were quantified. Purified complement proteins, complement-depleted serum, and complement receptor antibodies were used to investigate complement-mediated HCV-erythrocyte binding. Purified HCV-specific immunoglobulin G (IgG) from a chronic HCV-infected patient was used to study complement-mediated HCV-IC/erythrocyte binding. Binding of HCV to erythrocytes increased 200- to 1,000-fold after adding complement active human serum in the absence of antibody. Opsonization of free HCV occurred within 10 minutes, and peak binding to erythrocytes was observed at 20-30 minutes. Complement protein C1 was required for binding, whereas C2, C3, and C4 significantly enhanced binding. Complement receptor 1 (CR1, CD35) antibodies blocked the binding of HCV to erythrocytes isolated from chronically infected HCV patients and healthy blood donors. HCV-ICs significantly enhanced complement-mediated binding to erythrocytes compared to unbound HCV. Dissociation of complement-opsonized HCV from erythrocytes depended on the presence of Factor I. HCV released by Factor I bound preferentially to CD19⁺ B cells compared to other leukocytes. Conclusion: These results demonstrate that complement mediates the binding of free and IC-associated HCV to CR1 on erythrocytes and provide a mechanistic rationale for investigating the differential phenotypic expression of HCV-IC-related disease.

Clinical practice: hepatitis C virus infection, cryoglobulinemia and cryoglobulinemic vasculitis

Cryoglobulins are circulating immunoglobulins that reversibly precipitate at temperatures below 37 °C. Type-II cryoglobulins consist of monoclonal IgM/polyclonal IgG immune complexes (ICs), whereas in type-III cryoglobulins both IgM and IgG are polyclonal. The clinical condition resulting from the presence of cryoglobulins in the blood is called mixed cryoglobulinemia (MC), which can be asymptomatic or manifest as cryoglobulinemic vasculitis (CV). Type-I cryoglobulins, consisting of a single monoclonal isotype, are detected in patients with lymphoproliferative disorders. It is now established that > 90% of MCs are associated with HCV infection. Clinically, the spectrum of symptoms may range in severity from occasional purpuric eruptions to life-threatening features. In addition to the development of liver cirrhosis and hepatocellular carcinoma, the possible progression of HCV-positive CV patients to B-cell non-Hodgkin lymphoma (B-NHL) has been reported. The pathogenetic role played by HCV infection in the onset of B-NHL is suggested by regression of the latter following the achievement of a sustained virologic response (SVR). For several years, interferon-α alone or combined with ribavirin has been the standard of care. However, the rates of clinical, biochemical, and virologic responses have been low, and the occurrence of relapse frequent. The addition of rituximab has resulted in a higher rate of responses. With the advent of direct-acting antiviral agents, SVR has been achieved in ~ 95% of CV patients. However, in a minority of patients, despite SVR, CV may persist or reappear over variable lengths of time from the completion of therapy. The eventual appearance of B-NHL is also possible.