Hepatitis C virus infection in mixed cryoglobulinemia and B-cell non-Hodgkin's lymphoma: evidence for a pathogenetic role

Hepatitis C Virus (HCV)-Ribonucleic Acid (RNA) As a Biomarker for Lymphoid Malignancy with HCV Infection

The hepatitis C virus (HCV) is potentially associated with liver cancer, and advances in various drugs have led to progress in the treatment of hepatitis C and attempts to prevent its transition to liver cancer. Furthermore, reactivation of HCV has been observed in the treatment of lymphoma, during which the immortalization and proliferation of lymphocytes occur, which leads to the possibility of further stimulating cytokines and the like and possibly to the development of lymphoid malignancy. There are also cases in which the disappearance of lymphoid malignancy has been observed by treating HCV and suppressing HCV-Ribonucleic acid (RNA), as well as cases of recurrence with an increase in HCV-RNA. While HCV-associated lymphoma has a poor prognosis, improving the prognosis with Direct Acting Antivirals (DAA) has recently been reported. The reduction and eradication of HCV-RNA by means of DAA is thus important for the treatment of lymphoid malignancy associated with HCV infection, and HCV-RNA can presumably play a role as a biomarker. This review provides an overview of what is currently known about HCV-associated lymphoma, its epidemiology, the mechanisms underlying the progression to lymphoma, its treatment, the potential and limits of HCV-RNA as a therapeutic biomarker, and biomarkers that are expected now that DAA therapy has been developed.

COVID-19 and Mixed Cryoglobulinemia Syndrome: Long-Term Survey Study on the Prevalence and Outcome, Vaccine Safety, and Immunogenicity

PURPOSE

Mixed cryoglobulinemia syndrome (MCs) is a rare immunoproliferative systemic disorder with cutaneous and multiple organ involvement. Our multicenter survey study aimed to investigate the prevalence and outcome of COVID-19 and the safety and immunogenicity of COVID-19 vaccines in a large MCs series.

METHODS

The survey included 430 unselected MCs patients (130 M, 300 F; mean age 70 ± 10.96 years) consecutively collected at 11 Italian referral centers. Disease classification, clinico-serological assessment, COVID-19 tests, and vaccination immunogenicity were carried out according to current methodologies.

RESULTS

A significantly higher prevalence of COVID-19 was found in MCs patients compared to Italian general population (11.9% vs 8.0%, p < 0.005), and the use of immunomodulators was associated to a higher risk to get infected (p = 0.0166). Moreover, higher mortality rate was recorded in MCs with COVID-19 compared to those without (p < 0.01). Patients' older age (≥ 60 years) correlated with worse COVID-19 outcomes. The 87% of patients underwent vaccination and 50% a booster dose. Of note, vaccine-related disease flares/worsening were significantly less frequent than those associated to COVID-19 (p = 0.0012). Impaired vaccination immunogenicity was observed in MCs patients compared to controls either after the first vaccination (p = 0.0039) and also after the booster dose (p = 0.05). Finally, some immunomodulators, namely, rituximab and glucocorticoids, hampered the vaccine-induced immunogenicity (p = 0.029).

CONCLUSIONS

The present survey revealed an increased prevalence and morbidity of COVID-19 in MCs patients, as well an impaired immunogenicity even after booster vaccination with high rate of no response. Therefore, MCs can be included among frail populations at high risk of infection and severe COVID-19 manifestations, suggesting the need of a close monitoring and specific preventive/therapeutical measures during the ongoing pandemic.

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.

Global prevalence of hepatitis C in general population: A systematic review and meta-analysis

BACKGROUND

According to published reports from the World Health Organization, it is estimated that more than 3% of the world's population is infected with HCV. Given the impact of various factors on the prevalence of HCV in the world's population and the lack of general statistics around the world, this study aims to review the studies conducted in this field and statistical analysis of the results of general statistical studies on the prevalence of HCV in the world population.

METHODS

In this study, systematic review and meta-analysis of information of the studies related to the prevalence of HCV in the world using keywords including: Prevalence, HCV, Hepatitis C, Healthy Population, Healthy subjects, and General Population in SID, MagIran, IranMedex, IranDoc, ScienceDirect, Embase, Scopus, PubMed, Web of Science (WoS) databases and Google Scholar search engine were extracted without time limit until April 2020. In order to perform the analysis of qualified studies, the model of random effects was used, and the inconsistency of studies with I² index was investigated. Data analysis was performed with Comprehensive Meta-Analysis (Version 2).

RESULTS

In a study of 98 studies with a total sample size of 236,964 people in the world, the overall prevalence of HCV was 1.8% (95% CI: 1.4%-2.3%). Also, according to the subgroup analysis in different continents; the highest prevalence of HCV in the African continent was 7.1% (95% CI: 4.4-11.5%).

CONCLUSION

The results of this study show that the prevalence of hepatitis C in the world's population, especially in Africa, is almost high. Therefore, the officials of the World Health Organization should design measures to prevent the spread of this infection.

Autoantibodies and Rheumatologic Manifestations in Hepatitis C Virus Infection

HCV is a virus that can cause chronic infection which can result in a systemic disease that may include many rheumatologic manifestations such as arthritis, myalgia, sicca syndrome, cryoglobulinemia vasculitis as well as other non-rheumatological disorders (renal failure, onco-haematological malignancies). In this population, the high frequency of rheumatoid factor (45-70%), antinuclear (10-40%) and anticardiolipin (15-20%) antibodies is a B-cell mediated finding sustained by the infection. However, the possibility that a primitive rheumatic pathology may coexist with the HCV infection is not to be excluded thus complicating a differential diagnosis between primitive and HCV-related disorders.

Human Pegivirus Infection and Lymphoma Risk: A Systematic Review and Meta-analysis

BACKGROUND

Human pegivirus (HPgV) is a single-strand RNA virus belonging to the Flaviviridae. Although no definitive association between HPgV infection and disease has been identified, previous studies have suggested an association of HPgV viremia with risk of lymphomas.

METHODS

We conducted a systematic review and meta-analysis, including 1 cohort study and 14 case-control studies, assessing the association of HPgV viremia with adult lymphomas. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model, overall and by geographic region and lymphoma subtype.

RESULTS

The overall OR for lymphoma was 2.85 (95% CI, 1.98-4.11), with statistically significantly elevated ORs observed in 8 of 15 studies. There was a small amount of heterogeneity among studies (I2 = 28.9%; Q = 18.27, P = .16), and the funnel plot provided no evidence for publication bias. The strongest association with lymphoma risk was observed for studies from Southern Europe (OR, 5.68 [95% CI, 1.98-16.3]), whereas weaker ORs (with 95% CIs) were observed for studies from North America (2.24 [1.76-2.85]), Northern Europe (2.90 [.45-18.7), and the Middle East (2.51 [.87-7.27]), but all of similar magnitude. Participants with HPgV viremia had statistically significantly increased risks (OR [95% CI]) for developing diffuse large B-cell (3.29 [1.63-6.62]), follicular (3.01 [1.95-4.63]), marginal zone (1.90 [1.13-3.18]), and T-cell (2.11 [1.17-3.89]) lymphomas, while the risk for Hodgkin lymphoma (3.53 [.48-25.9]) and chronic lymphocytic leukemia (1.45 [.45-4.66]) were increased but did not achieve statistical significance.

CONCLUSIONS

This meta-analysis supports a positive association of HPgV viremia with lymphoma risk, overall and for the major lymphoma subtypes.

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.

Rheumatologic manifestations of hepatitis C in the era of direct-acting antiviral agents

Beyond the classic hepatic complications, hepatitis C (HCV) infection is considered as a systemic disease, since extrahepatic manifestations become clinically evident in 40% to 70% of the patients and it can frequently include rheumatic ones. Furthermore, HCV can promote the production of several autoantibodies, thus complicating the differential diagnosis between primitive and HCV-related rheumatic disorders. The recent development of direct-acting antivirals (DAA) against HCV has revolutionized the field, reducing the damage stemming from systemic inflammatory phenomena and persistent immune activation associated with continuous HCV replication. Our review focuses on the main rheumatologic manifestations associated with chronic HCV infection as well as the impact of DAA interferon-free treatments on such extrahepatic clinical involvement.

Rheumatologic manifestations of hepatic diseases

The course of hepatic diseases may be complicated by a multitude of rheumatologic manifestations, which can complicate the diagnostic approach and alter the natural history of primary liver disease, sometimes worsening prognosis due to associated multiple organ dysfunction. These manifestations can occur in association with a multitude of liver diseases, including viral hepatitis, autoimmune hepatitis, alcoholic liver disease, nonalcoholic fatty liver disease, hemochromatosis, or Wilson’s disease. It is necessary not only for rheumatologists, but also for other clinicians, to be aware that these atypical manifestations may reflect an undiagnosed hepatic disease. On the other hand, it is crucial that, in a patient with known hepatic disease presenting with rheumatologic symptoms, an accurate distinction be made between the rheumatologic manifestations of hepatic disease and primary rheumatologic disease, since the treatment is often different. This review aims to summarize the current evidence regarding rheumatologic manifestations of hepatic diseases, how to distinguish them from primary rheumatologic disorders, and how to provide adequate management.

Heterogeneity and coexistence of oncogenic mechanisms involved in HCV-associated B-cell lymphomas

The association of HCV-infection with B-lymphomas is supported by the regression of most indolent/low-grade lymphomas following anti-viral therapy. Studies on direct and indirect oncogenic mechanisms have elucidated the pathogenesis of HCV-associated B-lymphoma subtypes. These include B-lymphocyte proliferation and sustained clonal expansion by HCV-envelope protein stimulation of B-cell receptors, and prolonged HCV-infected B-cell growth by overexpression of an anti-apoptotic BCL-2 oncogene caused by the increased frequency of t(14;18) chromosomal translocations in follicular lymphomas. HCV has been implicated in lymphomagenesis by a "hit-and-run" mechanism, inducing enhanced mutation rate in immunoglobulins and anti-oncogenes favoring immune escape, due to permanent genetic damage by double-strand DNA-breaks. More direct oncogenic mechanisms have been identified in cytokines and chemokines in relation to NS3 and Core expression, particularly in diffuse large B-cell lymphoma. By reviewing genetic alterations and disrupted signaling pathways, we intend to highlight how mutually non-contrasting mechanisms cooperate with environmental factors toward progression of HCV-lymphoma.

Authentic Patient-Derived Hepatitis C Virus Infects and Productively Replicates in Primary CD4+ and CD8+ T Lymphocytes In Vitro

Accumulated evidence indicates that immune cells can support the replication of hepatitis C virus (HCV) in infected patients and in culture. However, there is a scarcity of data on the degree to which individual immune cell types support HCV propagation and on characteristics of virus assembly. We investigated the ability of authentic, patient-derived HCV to infect in vitro two closely related but functionally distinct immune cell types, CD4⁺ and CD8⁺ T lymphocytes, and assessed the properties of the virus produced by these cells. The HCV replication system in intermittently mitogen-stimulated T cells was adapted to infect primary human CD4⁺ or CD8⁺ T lymphocytes. HCV replicated in both cell types although at significantly higher levels in CD4⁺ than in CD8⁺ T cells. Thus, the HCV RNA replicative (negative) strand was detected in CD4⁺ and CD8⁺ cells at estimated mean levels ± standard errors of the means of 6.7 × 10² ± 3.8 × 10² and 1.2 × 10² ± 0.8 × 10² copies/μg RNA, respectively (P < 0.0001). Intracellular HCV NS5a and/or core proteins were identified in 0.9% of CD4⁺ and in 1.2% of CD8⁺ T cells. Double staining for NS5a and T cell type-specific markers confirmed that transcriptionally competent virus replicated in both cell types. Furthermore, an HCV-specific protease inhibitor, telaprevir, inhibited infection in both CD4⁺ and CD8⁺ cells. The emergence of unique HCV variants and the release of HCV RNA-reactive particles with biophysical properties different from those of virions in plasma inocula suggested that distinct viral particles were assembled, and therefore, they may contribute to the pool of circulating virus in infected patients.IMPORTANCE Although the liver is the main site of HCV replication, infection of the immune system is an intrinsic characteristic of this virus independent of whether infection is symptomatic or clinically silent. Many fundamental aspects of HCV lymphotropism remain uncertain, including the degree to which different immune cells support infection and contribute to virus diversity. We show that authentic, patient-derived HCV productively replicates in vitro in two closely related but functionally distinct types of T lymphocytes, CD4⁺ and CD8⁺ cells. The display of viral proteins and unique variants, the production of virions with biophysical properties distinct from those in plasma serving as inocula, and inhibition of replication by an antiviral agent led us to ascertain that both T cell subtypes supported virus propagation. Infection of CD4⁺ and CD8⁺ T cells, which are central to adaptive antiviral immune responses, can directly affect HCV clearance, favor virus persistence, and decisively influence the development and progression of hepatitis C.

International therapeutic guidelines for patients with HCV-related extrahepatic disorders. A multidisciplinary expert statement

Hepatitis C virus (HCV) is both hepatotrophic and lymphotropic virus that causes liver as well extrahepatic manifestations including cryoglobulinemic vasculitis, the most frequent and studied condition, lymphoma, and neurologic, cardiovascular, endocrine-metabolic or renal diseases. HCV-extrahepatic manifestations (HCV-EHMs) may severely affect the overall prognosis, while viral eradication significantly reduces non-liver related deaths. Different clinical manifestations may coexist in the same patient. Due to the variety of HCV clinical manifestations, a multidisciplinary approach along with appropriate therapeutic strategies are required. In the era of interferon-free anti-HCV treatments, international recommendations for the therapeutic management of HCV-EHMs are needed. This implies the need to define the best criteria to use antivirals and/or other therapeutic approaches. The present recommendations, based on qualified expert experience and specific literature, will focus on etiological (antiviral) therapies and/or traditional pathogenetic treatments that still maintain their therapeutic utility.

Virus-driven autoimmunity and lymphoproliferation: the example of HCV infection

HCV chronic infection is characterized by possible development of both hepatic and extrahepatic manifestations. The infection by this both hepatotropic and lymphotropic virus is responsible for polyoligoclonal B-lymphocyte expansion, leading to several immune-mediated disorders. Mixed cryoglobulinemia syndrome that in some cases may evolve to frank B-cell non-Hodgkin's lymphoma is the prototype of HCV-driven autoimmune and lymphoproliferative disorders. The HCV oncogenic potential has been suggested by several clinicoepidemiological and laboratory studies; it includes hepatocellular carcinoma, B-cell non-Hodgkin's lymphoma and papillary thyroid cancer. The definition HCV syndrome refers to the complex of HCV-driven diseases; these latter are characterized by heterogeneous geographical distribution, suggesting a role of other important genetic and/or environmental cofactors. The natural history of HCV syndrome is the result of a multifactorial and multistep pathogenetic process, which may evolve from mild manifestations to systemic autoimmune disorders, and less frequently to malignant neoplasias. The present updated review analyzes the clinical and pathogenetic aspects of the main HCV-associated diseases.

Deregulation of microRNA expression in peripheral blood mononuclear cells from patients with HCV-related malignancies

BACKGROUND AND AIM

Hepatocellular carcinoma is one of the major causes of death due to cancer worldwide, and its association with hepatitis C virus infection has been definitively established. Hepatitis C virus is also involved in the pathogenesis of non-Hodgkin's lymphoma. This is the only virus infecting humans that is able to induce two different malignancies. We analyzed the expression levels of a panel of microRNA in peripheral blood mononuclear cells of patients with hepatitis C virus-related malignancies in order to find a disease-associated deregulation and identify specific biomarkers.

METHODS

We tested peripheral blood mononuclear cells isolated from patients with hepatocellular carcinoma, non-Hodgkin's lymphoma, hepatitis C virus without malignancies and healthy subjects for a panel of microRNA selected on the basis of previous studies. MicroRNA expression was evaluated by real-time PCR.

RESULTS

Our results showed an upregulation of miRNA-21 and downregulation of miRNA-26b in hepatocellular carcinoma and non-Hodgkin's lymphoma patients compared to controls (p < 0.001). Deregulation of miRNA-16 and miRNA-155 was limited to lymphoma patients.

CONCLUSIONS

This study shows that some microRNAs are differently expressed in peripheral blood mononuclear cells from hepatitis C virus patients who develop hepatocellular carcinoma or lymphoma, while others share a common behavior. Thus, analysis of the expression of microRNAs could be a noninvasive marker of hepatitis C virus-related carcinogenesis. This analysis could be a suitable tool for identifying the existence of a malignancy and also discriminating between these two hepatitis C virus-related cancers.

Hepatitis C virus and lymphoma

Hepatitis C virus (HCV) is a hepatotrophic and lymphotrophic virus and is a global health problem. Cirrhosis and hepatocellular cancer are the most common complications of HCV. Association between HCV and B cell non-Hodgkin lymphomas (B-NHL) has been shown in epidemiological studies in the last 20 years. High prevalence of HCV infection among patients with NHL has been reported in the early 1990s by Ferri in Italy and this association has been confirmed in later studies. Geographically, HCV related NHL is highly variable and chronic rather than cleared HCV infection is required for lymphomagenesis. Although anti-HCV antibody test is the most commonly used technique in epidemiological studies, HCV-RNA is more useful test to detect the association between HCV and NHL. The optimal management of HCV related NHL is not clear. However, anti-viral treatment may be sufficient for cases with low grade and/or asymptomatic lymphomas, while immuno-chemotherapy is necessary, in spite of probable hepatic toxicity, in cases with high grade lymphomas.

Waldenström macroglobulinemia in hepatitis C: case report and review of the current literature

Background. Recent literature has associated hepatitis C virus with the development of non-Hodgkin lymphoma. Hepatitis C virus infection appears to promote lymphoproliferation, providing a plausible mechanism for a causative association; however, despite prior reports of patients with comorbid hepatitis C infection and Waldenström macroglobulinemia, the literature is in disagreement regarding whether there exists an association between these two conditions. Case Presentation. This case report describes a 57-year-old African-American male with chronic hepatitis C infection and cryoglobulinemia who presented with several episodes of transient confusion and paralysis and was found to have symptomatic hyperviscosity. The recognition of his condition was facilitated by characteristic findings on ophthalmologic examination. He was subsequently diagnosed with Waldenström macroglobulinemia on bone marrow biopsy. Conclusions. An up to date, comprehensive review of the literature suggests an association between hepatitis C and Waldenström macroglobulinemia. Data on optimal treatment of patients with comorbid hepatitis C infection and Waldenström macroglobulinemia is limited. We have provided a comprehensive review of previously explored treatment options to guide management of other similar patients. Our patient has since been treated with repeated plasmapheresis with a plan to pursue antiviral therapy.

Assessment of total hepatitis C virus (HCV) core protein in HCV-related mixed cryoglobulinemia

Introduction

In hepatitis C virus (HCV)-related mixed cryoglobulinemia (MCG), the nonenveloped HCV core protein (HCV-Cp) is a constituent of the characteristic cold-precipitating immune complexes (ICs). A possible correlation between HCV-Cp, virologic, laboratory, and clinical parameters in both untreated MCG patients and those undergoing specific treatment was explored.

Methods

HCV-Cp was quantified by a fully automated immune assay. Correlations between HCV-Cp and HCV RNA, cryocrit, and virus genotype (gt) were investigated in 102 chronically HCV-infected MCG patients.

Results

HCV-Cp concentrations strongly correlated with HCV RNA levels in baseline samples. An average ratio of 1,425 IU and 12,850 IU HCV RNA per picogram HCV-Cp was estimated in HCV gt-1 and gt-2 patients, respectively. This equation allowed us to estimate that, on average, HCV-Cp was associated with the viral genome in only 3.4% of the former and in 35% of the latter group of patients. The direct relation between HCV-Cp and the cryocrit level suggests that the protein directly influences the amount of cryoprecipitate. Although the therapy with rituximab (RTX) as a single agent resulted in the enhancement of HCV-Cp levels, in patients treated with RTX in combination with a specific antiviral therapy (pegylated interferon-α plus ribavirin), the prompt and effective clearance of HCV-Cp was documented.

Conclusions

Our data provide evidence that HCV-Cp has a direct effect on the cold-precipitation process in a virus genotype-dependence in HCV-related MCG patients.

Value of IL28B genotyping in patients with HCV-related mixed cryoglobulinemia: results of a large, prospective study

HCV-related mixed cryoglobulinemia (MC) is characterized by clonal expansion of B cells producing a polyreactive natural antibody (rheumatoid factor) and interferon (IFN)-based therapy is the first therapeutic option in mild-moderate MC. Single nucleotide polymorphisms (SNPs) proximal to genes involved in the innate response (IL28B/IFN-λ gene family) are strongly associated with spontaneous and IFN-induced viral clearance in hepatitis C, but no data exist about their role in HCV-positive MC. A large cohort of patients with HCV and MC was studied to evaluate the influence of IL28B genotype on the response to treatment and/or the evolution to MC of HCV infection. The rs12979860/rs8099917 IL28B polymorphisms were analysed in 481 consecutive HCV-positive subjects (250 with MC and 231 without MC, as controls) using real-time PCR and direct sequencing. Hundred and fifteen HCV patients with MC received standard anti-HCV therapy, and the results were evaluated according to the IL28B SNP distribution. Similar IL28B SNPs allele frequencies were recorded for patients and controls. IL28B major allele homozygosis (for both SNPs tested) was tightly correlated with virological and clinical response (P = 0.002). A statistically significant association was limited to 'difficult-to-treat' (G1/4) HCV genotypes. The IL28B genotype was a strong independent predictor of response (P = 0.007, OR 6.06; CI 1.65-22.22). The IL28B genotype was confirmed to be a useful predictor of response to IFN-based therapy in patients with HCV and MC. The very close correlation between IL28B SNP distribution, virological and clinical response definitively confirmed the key role played by HCV in MC. Conversely, the IL28B genotype does not seem to influence the evolution to MC.

Hepatitis C virus: the role of molecular mimicry in response to interferon treatment

Chronic hepatitis C virus (HCV) infection is one of the major causes of chronic liver disease worldwide. In order for HCV to persist, the virus must escape immune recognition or inhibit the host immune response. The NS5A protein contains the interferon sensitivity-determining region (ISDR) and is able to repress dsRNA-dependent protein kinase (PKR) thus influencing the response to interferon (IFN) therapy. Patients who respond to IFN therapy have stronger antibody reactivity against the NS5A compared to IFN non-responders. Therefore, given the possible role for the ISDR in IFN resistance and differential antibody reactivity, it is possible that variation in ISDR may be involved in viral immune escape and development of persistent HCV infection employing aspects of host mimicry. In this study, pre-treatment samples obtained from HCV infected patients were used to investigate the effect of different NS5A ISDR variants on the IFN antiviral response and their involvement in immune evasion. The NS5A was identified as a homologue of the variable region of immunoglobulins (Ig). The IFN resistant genotypes had higher levels of similarity to Ig compared to IFN sensitive genotypes. Expression of NS5A-6003 (HCV genotype 1b) and NS5A-6074 (HCV genotype 2a) was able to rescue vesicular stomatitis virus (VSV) from IFN inhibition and restore luciferase activity. A correlation between Ig-like NS5A structure and also antibody response with the outcome of IFN treatment was observed.

Hepatitis C virus infection and autoimmune diseases

Hepatitis C virus (HCV) infection is associated with a number of extrahepatic disorders. The most studied conditions associated with HCV are type II mixed cryoglobulinemia and B cell lymphoma. However, many reports suggest that HCV might also be associated with a number of autoimmune disorders, both organ-specific and not organ-specific. Although concomitant treatment of HCV infection is a confounding factor when ascertaining the actual role of HCV in inducing autoimmune disease, a considerable amount of experimental data indicates that HCV is able to subvert the immune system and consequently induce autoimmunity. In the present review, we report a series of observations which associate chronic HCV infection with the onset of autoimmune disorders.

The hepatitis C virus infection as a systemic disease

Hepatitis C Virus (HCV) is a major health problem, infecting about 3 % of people worldwide and leading to liver as well as extrahepatic diseases. This justifies the definition of HCV infection as a systemic disease. Based on available data, the link between the virus and some of these extrahepatic disorders is certain, whereas for some others needs further confirmation. HCV-related lymphoproliferative disorders, ranging from benign, but pre-lymphomatous conditions, like mixed cryoglobulinemia, to frank lymphomas, represent the extrahepatic manifestations most closely related to HCV. The primary involvement of the liver and lymphatic system corresponds to the double viral tropism, being HCV able to infect both hepatic and lymphatic cells. Other HCV-associated disorders include renal, endocrine, dermatological, cardiovascular, rheumatologic and central nervous system diseases. On the whole, the HCV disease appears a very important, mainly hidden, public health problem leading to heavy direct and indirect costs. The possibility that HCV may be eradicated following antiviral therapy is important for both the therapeutic and preventive points of view, making the HCV disease an ideal model for pathogenetic studies.

[Neuropathies in the course of primary hepatotropic virus infections]

The primary hepatotropic viruses are associated with various extrahepatic manifestations including peripheral nervous system disorders. The pathogenesis of these complications is not clear-cut. Patients with confirmed liver damage coexisting with peripheral nervous system manifestations, especially Guillain-Barré syndrome, mononeuropathy, mononeuropathy multiplex and polyneuropathy should be screened for the viral hepatitis in the differential diagnosis. There are no defined strategies of treatment for these manifestations, so the therapy should be individualized. The purpose of this review is to discuss the etiology, pathogenesis and treatment of the neuropathies in the course of primary hepatotropic viral infections such as hepatitis A, B, C and E viruses.

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

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

HCV and lymphoproliferation

Hepatitis C virus (HCV) infection is a serious public health problem because of its worldwide diffusion and sequelae. It is not only a hepatotropic but also a lymphotropic agent and is responsible not only for liver injury--potentially evolving to cirrhosis and hepatocellular carcinoma--but also for a series of sometimes severely disabling extrahepatic diseases and, in particular, B-cell lymphoproliferative disorders. These latter range from benign, but prelymphomatous conditions, like mixed cryoglobulinemia, to frank lymphomas. Analogously with Helicobacter pylori related lymphomagenesis, the study of the effects of viral eradication confirmed the etiopathogenetic role of HCV and showed it is an ideal model for better understanding of the molecular mechanisms involved. Concerning these latter, several hypotheses have been proposed over the past two decades which are not mutually exclusive. These hypotheses have variously emphasized the important role played by sustained stimulation of the immune system by HCV, infection of the lymphatic cells, viral proteins, chromosomal aberrations, cytokines, or microRNA molecules. In this paper we describe the main hypotheses that have been proposed with the corresponding principal supporting data.

Human cell types important for hepatitis C virus replication in vivo and in vitro: old assertions and current evidence

Hepatitis C Virus (HCV) is a single stranded RNA virus which produces negative strand RNA as a replicative intermediate. We analyzed 75 RT-PCR studies that tested for negative strand HCV RNA in liver and other human tissues. 85% of the studies that investigated extrahepatic replication of HCV found one or more samples positive for replicative RNA. Studies using in situ hybridization, immunofluorescence, immunohistochemistry, and quasispecies analysis also demonstrated the presence of replicating HCV in various extrahepatic human tissues, and provide evidence that HCV replicates in macrophages, B cells, T cells, and other extrahepatic tissues. We also analyzed both short term and long term in vitro systems used to culture HCV. These systems vary in their purposes and methods, but long term culturing of HCV in B cells, T cells, and other cell types has been used to analyze replication. It is therefore now possible to study HIV-HCV co-infections and HCV replication in vitro.

Persistent infection by HCV and EBV in peripheral blood mononuclear cells and risk of non-Hodgkin's lymphoma

Hepatitis C virus (HCV) and Epstein-Barr virus (EBV) have been repeatedly associated with risk of non-Hodgkin's lymphoma (NHL) in studies focusing on serological evidence of infection. We investigated NHL risk in association with detection of HCV-RNA or EBV-DNA in the peripheral blood mononuclear cells (PBMC). The study involved 91 NHL cases and 182 controls nested in the Italian branch of the EPIC (European Prospective Investigation of Cancer and nutrition) cohort, which obtained blood samples from 47,749 healthy volunteers between 1993 and 1998 in 5 Italian cities. NHL cases were identified until June 2005 through linkage with records of the Cancer, Mortality, and Hospital Discharge Registries. For all study subjects, we performed viral genome analyses on DNA and RNA extracted from buffy-coats and analysed EBV and HCV antibodies. The odds ratios (ORs) of NHL were 1.2 (95% confidence intervals: 0.4-3.8; 5 exposed cases) for PBMC HCV infection and 1.2 (0.7-2.3; 24 exposed cases) for PBMC EBV infection. Similar OR estimates were found for detection of EBV and HCV antibodies. These null results, although based on a relatively small sample size, suggest that persistent EBV and HCV infection in the PBMC is not a stronger predictor of NHL risk than serological evidence of infection.

Occult hepatitis C virus infection: what does it mean?

Occult hepatitis C virus infection (OCI) is a recently identified entity of which the existence became evident when nucleic acid amplification assays of enhanced sensitivity were introduced for the detection of hepatitis C virus (HCV) genome and its replication. This form of HCV infection has been found to persist in the presence of antibodies against HCV and normal levels of liver enzymes for years after spontaneous or antiviral therapy-induced resolution of hepatitis C and, therefore, can be termed as secondary OCI. HCV RNA in OCI circulate at fluctuating levels normally not exceeding 200 genome copies per millilitre of serum or plasma, while low levels of virus genome and its replicative intermediate RNA-negative strand are detectable in the liver and, importantly, immune cells, which provide an opportunity to detect active virus replication without the need for acquiring a liver biopsy. In addition to secondary OCI, a form of OCI accompanied by persistently moderately elevated serum liver enzymes in the absence of antibodies to HCV, which can be termed as cryptogenic OCI, has also been described. The current understanding of the nature and characteristics of OCI, methods and pitfalls of its detection, as well as the documented and expected pathological consequences of OCI will be summarized in this review.

Chronic hepatitis C and persistent occult hepatitis C virus infection are characterized by distinct immune cell cytokine expression profiles

Hepatitis C virus (HCV) replicates in immune cells in both chronic hepatitis C (CHC) and occult HCV infection, but the extent of virus replication in this compartment in these opposing infection forms varies greatly. It was unknown whether this could be linked to HCV genotype or to differences in host gene expression shaping the immune response, and whether HCV replication in immune cells is sensitive to endogenous antiviral cytokines. In this study, we uncovered that significantly greater HCV load in peripheral blood mononuclear cells (PBMC), but not in plasma, coincided with HCV genotypes 2 and 3 in CHC, but with genotype 1 in residual occult infection after clinical resolution of hepatitis C. Moreover, PBMC from individuals with occult infection transcribed significantly greater levels of IFN-alpha, IFN-gamma and TNF-alpha, but less interleukin (IL)-10 than those from CHC. In CHC, PBMC with low HCV load expressed significantly more IFN-gamma but less IL-12 than did cells with high virus content. In occult infection, HCV RNA detection in PBMC was associated with much lower IFN-alpha and IL-12 expression. Further, HCV replication in T lymphocytes could be completely eliminated by activation of endogenous IFN-gamma in CHC, but of IFN-alpha in occult infection. In conclusion, CHC and persistent occult HCV infection are characterized by clearly different profiles of antiviral cytokine response in circulating immune cells which are also different from those of healthy individuals. Higher expression of IL-10, combined with lower transcription of IFN-alpha, IFN-gamma and TNF-alpha, is associated with a more robust HCV replication in immune cells.

Hepatitis C virus-induced cryoglobulinemia

In this review we discuss the clinical manifestations, pathogenesis, and treatment of hepatitis C virus (HCV)-related cryoglobulinemia. HCV is a major cause of liver-related morbidity and is increasingly recognized as an instigator of B-cell lymphoproliferative disorders such as mixed cryoglobulinemia and non-Hodgkin lymphoma. Cryoglobulinemia is characterized by the clonal expansion of rheumatoid factor-expressing B cells in the liver, lymph nodes, and peripheral blood, resulting in the presence of cryoglobulins in the circulation. Cryoglobulins are cold-insoluble immune complexes containing rheumatoid factor, polyclonal IgG, and HCV RNA that precipitate and deposit on vascular endothelium, causing vasculitis in organs such as the skin, kidneys, and peripheral nerves. A subset of patients develops a low-grade lymphoma composed of B cells that are immunophenotypically similar to the expanded B cells seen in cryoglobulinemia. HCV-related B-cell lymphoproliferative disorders likely comprise a spectrum of disease, ranging from asymptomatic clonal B-cell expansions to pathogenic cryoglobulinemia and lymphoma. It is unclear how B cells become dysregulated during the course of chronic HCV infection, and continued patient-centered research is necessary to elucidate the pathogenesis of HCV-related B-cell dysregulation.

Lack of an association betweenChlamydia psittaciand ocular adnexal lymphoma

The objective of this study was to assess whether there is PCR evidence for C. psittaci DNA in ocular adnexal lymphoma specimens collected in an academic institution in the U.S. This was a retrospective, single-center study of patients from 1994 - 2004. We used 28 ocular adnexal lymphoma biopsy specimens from adult patients, 16 control lymphoma specimens from patients with systemic lymphomas not involving the ocular adnexa, and five control benign adnexal tissue samples. The presence of C. psittaci DNA was investigated by polymerase chain reaction (PCR) in each group. Two different assays were utilized: (1) conventional PCR/gel based assay targeting a 111-bp fragment of the 16S gene and (2) a real-time PCR assay amplifying a 148-bp portion of the 16S gene with detection via a specific fluorescent probe. Amplification was carried out to 60 cycles. Positive controls consisted of isolated DNA from C. psittaci strains VS1, CP3, and FP. A human DNA internal control was used to assess sample DNA quality and amplification success. Mean outcome measure was the presence of C. psittaci DNA. Using both assays, all patient samples in all categories yielded negative results. Both assays detected C. psittaci DNA from isolated strains. Internationally, Chlamydia psittaci has been associated with ocular adnexal lymphomas with great variability. Similar to several other recent studies in the USA, our study could not confirm the presence of C. psittaci in ocular adnexal lymphomas. Differences in the prevalence of C. psittaci infection in various geographic regions or technical differences in the application of the assays may underlie the variability in the association between C. psittaci and ocular adnexal lymphoma.

Hematopoietic malignancies associated with viral and alcoholic hepatitis

Hepatitis C virus (HCV) and hepatitis B virus (HBV) have been associated with hematopoietic malignancies, but data for many subtypes are limited. From the U.S. Surveillance, Epidemiology, and End Results-Medicare database, we selected 61,464 cases (> or = 67 years) with hematopoietic malignancies and 122,531 population-based controls, frequency-matched by gender, age, and year (1993--2002). Logistic regression was used to compare the prevalence of HCV, HBV, and alcoholic hepatitis in cases and controls, adjusted for matching factors, race, duration of Medicare coverage, and number of physician claims. HCV, HBV, and alcoholic hepatitis were reported in 195 (0.3%), 111 (0.2%), and 404 (0.7%) cases and 264 (0.2%), 242 (0.2%), and 798 (0.7%) controls, respectively. HCV was associated with increased risk of diffuse large B-cell lymphoma [odds ratio (OR) 1.52, 95% confidence interval (95% CI) 1.05-2.18], Burkitt lymphoma (OR 5.21, 95% CI 1.62-16.8), follicular lymphoma (OR 1.88, 95% CI 1.17-3.02), marginal zone lymphoma (OR 2.20, 95% CI 1.22-3.95), and acute myeloid leukemia (OR 1.54, 95% CI 1.00-2.37). In contrast, HBV was unrelated to any hematopoietic malignancies. Alcoholic hepatitis was associated with decreased risk of non-Hodgkin lymphoma overall, but increased risk of Burkitt lymphoma. In summary, HCV, but not other causes of hepatitis, was associated with the elevated risk of non-Hodgkin lymphoma and acute myeloid leukemia. HCV may induce lymphoproliferative malignancies through chronic immune stimulation.

Extrahepatic manifestations of hepatitis C virus infection

Hepatitis C virus may cause hepatic and extrahepatic diseases. Extrahepatic manifestations range from disorders for which a significant association with viral infection is supported by epidemiologic and pathogenetic data, to anecdotal observations without clear proof of causality. This article describes the diagnosis and treatment of these diseases.

Hepatitis C infection and risk of malignant lymphoma

The association between hepatitis C virus (HCV) infection and risk of malignant lymphoma remains controversial, perhaps due to small-sized studies and low prevalence of HCV in the general population. On the basis of a large Danish-Swedish population-based case-control study, 2,819 lymphoma patients and 1,856 controls of second-generation Danish-Swedish origin were screened for HCV infection using an enzyme-linked immunosorbent assay and a confirming recombinant immunoblot assay (RIBA) test. Positive samples were tested with real-time PCR for the presence of HCV RNA. The association between HCV infection and risk of malignant lymphoma was assessed by logistic regression. When intermediate RIBA test results were interpreted as positive, anti-HCV antibody positivity was associated with a nonsignificant increased risk of non-Hodgkin lymphoma (NHL) overall (odds ratio (OR) = 2.2; 95% confidence interval (CI) 0.9-5.3; n = 20 cases), of B-cell lymphomas combined (OR = 2.4 [1.0-5.8]; n = 20) and of lymphoplasmacytic lymphoma (OR = 5.2 [1.0-26.4]; n = 2). No patients with T-cell or Hodgkin lymphoma were HCV-positive. A more conservative definition of HCV positivity (disregarding intermediate RIBA results) resulted in an OR = 1.6 (0.3-8.5; n = 5) for NHL overall. When the definition was further restricted to require HCV RNA positivity, OR was 1.7 (0.2-16.2; n = 3) for NHL overall. Our findings from a population with a low prevalence of HCV suggest a positive association between HCV and risk of NHL, in particular of B-cell origin.

Hepatitis C virus (HCV) infection: a systemic disease

Hepatitis C virus (HCV) infection is a global health problem, being the second most common chronic viral infection in the world with a global prevalence of about 3% (about 180 million people). HCV is both an hepatotropic and a lymphotropic virus; and chronic infection could cause, on one hand, chronic hepatitis, cirrhosis and hepatocellular carcinoma and on the other hand several extrahepatic diseases including, first, mixed cryoglobulinemia and lymphoma. The association between hepatic (hepatocellular carcinoma) and extrahepatic (lymphoma, thyroid cancer) malignancies has justified the inclusion of HCV among human cancer viruses. The pathogenesis of HCV-related sequelae (hepatic or extrahepatic) is not fully understood representing a challenge of prime importance in light of the optimization of clinico-therapeutic management of these patients. Combined treatment with pegylated interferon plus ribavirin is presently the first-line, gold standard treatment of most HCV-related diseases. However, mainly in the case of extrahepatic manifestations, a cautious approach to the patient, with a case to case accurate tailoring of therapy is frequently requested. The present review will outline the principal aspects of such HCV-induced systemic disease focusing on extrahepatic manifestations.

Hepatitis C virus-related lymphoproliferative disorders: An overview

Hepatitis C virus (HCV) is a global health problem affecting 3% of the world's population (about 180 million) and a cause of both hepatic and extrahepatic diseases. B-cell lymphoproliferative disorders, whose prototype is mixed cryoglobulinemia, represent the most closely related as well as the most investigated HCV-related extrahepatic disorder. The association between extrahepatic (lymphoma) as well as hepatic malignancies (hepatocellular carcinoma) has justified the inclusion of HCV among human cancer viruses. HCV-associated manifestations also include porphyria cutanea tarda, lichen planus, nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, diabetes, chronic polyarthritis, sexual dysfunctions, cardiopathy/atherosclerosis, and psychopathological disorders. A pathogenetic link between HCV virus and some lymphoproliferative disorders was confirmed by their responsiveness to antiviral therapy, which is now considered the first choice treatment. The aim of the present paper is to provide an overview of extrahepatic manifestations of HCV infection with particular attention to B-cell lymphoproliferative disorders. Available pathogenetic hypotheses and suggestions about the most appropriate, currently available, therapeutic approaches will also be discussed.

Extrahepatic manifestations of Hepatitis C Virus infection: a general overview and guidelines for a clinical approach

Hepatitis C Virus is associated with a wide series of extrahepatic manifestations. Based on available data the link between the virus and some of these extrahepatic diseases is only suggested and needs further confirmation. Hepatitis C Virus-related lymphoproliferative disorders, whose prototype is mixed cryoglobulinaemia, represent the most closely related extrahepatic manifestations of Hepatitis C Virus. Other Hepatitis C Virus-associated disorders include nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, porphyria cutanea tarda, lichen planus, diabetes, chronic polyarthritis, cardiopathy and atherosclerosis. A pathogenetic link between Hepatitis C Virus and some extrahepatic manifestations was confirmed by their responsiveness to antiviral therapy, which is now deemed the first therapeutic option to consider. By contrast, there are diseases where treatment with interferon was ineffective or dangerous. The aim of the present paper is to outline the most recent evidence concerning extrahepatic disorders that are possibly associated with Hepatitis C Virus infection. Special emphasis will be given to discussion of the most appropriate clinical approaches to be adopted in order to diagnose, treat (possibly prevent) and follow-up extrahepathic diseases in patients with Hepatitis C Virus infection.

Hepatic B-cell non-Hodgkin's lymphoma of MALT type in the liver explant of a patient with chronic hepatitis C infection

B-cell non-Hodgkin's lymphoma (B-NHL) is a well-documented complication of hepatitis C virus (HCV) infection. Marginal zone (mucosa-associated lymphoid tissue; MALT) lymphomas constitute a less common type of B-NHL. In this article, we report a case of liver MALT in a cirrhotic patient, incidentally discovered after liver transplantation (LT). We discuss pertinent diagnostic and management strategies in this clinical setting.

Hepatitis C virus-associated extrahepatic manifestations: a review

The hepatitis C virus (HCV) infection is a worldwide disease that is characterized by a preferential chronic evolution with mild to severe liver disease, including cirrhosis and, in lesser proportion, hepatocarcinoma. Out of these complications, HCV is frequently reported to complicate extrahepatic manifestations. Among those associated to HCV infection with a high degree of certainty, mixed cryoglobulinemia and its complications (skin, neurological, renal, rheumatological involvement) are the most prevalent (50%) in HCV-infected patients. The other diseases include noncryoglobulinemic systemic vasculitis, splenic lymphoma with villous lymphocytes, fatigue, porphyria cutanea tarda, sicca syndrome, and autoantibodies production. The extrahepatic manifestations that share mild-degree certainty of association with HCV infection include B-cell non-Hodgkin lymphoma, autoimmune thrombocytopenia, pruritus, and type II diabetes mellitus. The other diseases such as autoimmune thyroiditis, lichen planus are more questionable for their eventual association with HCV and others (pulmonary fibrosis with or without polymyositis, progressive encephalomyelitis, Mooren's corneal ulcers, erythema nodosum, chronic polyradiculonevritis) are mostly case reports. Howerver, even in cases of tight association, the mechanisms through which HCV may promote or induce extrahepatic manifestations remain unclear and merit further investigations.

Response to antiviral treatment in hepatitis C virus-associated marginal zone lymphomas

A link between chronic hepatitis C virus (HCV) infection and low-grade B-cell lymphomas has been suggested by epidemiological studies. Marginal zone lymphomas (MZLs) including splenic lymphomas with villous lymphocytes are among the most frequently reported subgroups in the setting of chronic HCV infection. In this study, we examined the effect of antiviral treatment in eight patients with HCV-associated MZL. We found that five out of eight patients have responded to interferon alpha and ribavirin. In some cases, hematologic responses were correlated to virologic responses. In addition, we report a case of large granular lymphocyte leukemia occurring in association with MZL and HCV, and responding to interferon and ribavirin. We suggest that there is an etiologic link between HCV and antigen-driven lymphoproliferative disorders.

Role of hepatitis C virus infection in malignant lymphoma in Spain

Hepatitis C virus (HCV) has been implicated in the etiology of malignant lymphomas. We estimated the risk of lymphoma associated with detection of HCV infection. Cases (n = 529) were consecutive patients newly diagnosed with a lymphoid malignancy between 1998 and 2002 in 4 centers in Spain. Lymphomas were diagnosed and classified using the WHO Classification. Controls (n = 600) were hospitalized patients matched to the cases by 5-year age group, gender and study center. Several medical conditions associated with severe immunosuppression precluded the eligibility of controls. Patients underwent a personal interview and blood sampling. HCV positive subjects were considered those with antibody response to third generation ELISA or detection of HCV RNA with Amplicor 2.0. Cases were systematically tested for HIV antibodies. We used the chi(2) test and unconditional logistic regression to estimate the odds ratio (OR) and 95% confidence interval (95% CI) for lymphoma associated with HCV. HCV infection was detected in 40 cases (7.5%) and 23 (3.8%) control subjects. Six of 16 patients with HIV-related lymphomas and 4 of 8 organ-recipient-related lymphomas were HCV positive. The analysis, excluding HIV-infected subjects and organ recipients, led to a prevalence of HCV of 5.9% among cases and 3.8% among controls. The age-, gender- and center-adjusted OR for all lymphomas was 1.58 (95% CI = 0.89-2.79). Among all lymphoma categories, HCV was associated with an increased risk of low grade B-cell lymphomas not otherwise specified (NOS) (OR = 35.98, 95% CI = 4.70-275.4). A 2-fold excess risk associated to HCV was observed for marginal B-cell lymphomas, diffuse large B-cell lymphoma and lymphoma B NOS but the associations were not statistically significant. HCV infection is associated with an increased risk of a broad spectrum of lymphoid neoplasms among non severely immunocompromised subjects in Spain.

Hepatitis C Virus and Risk of Non-Hodgkin Lymphoma: A Population-Based Case-Control Study among Connecticut Women

Objective: Previous epidemiologic studies of hepatitis C virus (HCV) infection and B-cell non-Hodgkin lymphoma (B-NHL) have yielded conflicting results, perhaps due to differences in the classification of B-NHL and the choice of non-population-based control groups that may not reflect the background population prevalence of HCV. To further investigate the link between HCV and NHL, we conducted HCV testing on serum samples of 998 women (464 cases; 534 controls) from a population-based case-control study of women in Connecticut. Methods: Serum samples were screened for HCV antibodies using an enzyme immunoassay; positive samples were confirmed by additional testing for HCV antibodies and for serum HCV RNA. Results: Approximately 2% (8 of 464) of cases and 1% (5 of 534) of controls tested positive for HCV. The risk of NHL associated with HCV infection appeared to be concentrated among B-cell lymphomas [odds ratio (OR) 2.0; 95% confidence interval (CI) 0.6, 8.2], particularly among follicular lymphomas (OR 4.1, 95% CI 0.8, 19.4). Conclusion: The primary strength of this study is our use of a population-based study design, although the low prevalence of HCV among women in Connecticut resulted in wide CIs for the estimated association between HCV and B-NHL subtypes. Our study suggests that HCV may be associated with increased risk of development of B-NHL, and that this risk may vary by B-NHL subtype among women. Due to the relatively low prevalence of HCV in our study population and the scarcity of population-based epidemiological research on this subject, our study highlights the need for additional large, population-based studies of the role of HCV in the etiology of B-NHL.