Sustained response to interferon-alpha or to interferon-alpha plus ribavirin in hepatitis C virus-associated symptomatic mixed cryoglobulinaemia

Cryoglobulinemic glomerulonephritis: clinical presentation and histological features, diagnostic pitfalls and controversies in the management. State of the art and the experience on a large monocentric cohort treated with B cell depletion therapy

Cryoglobulinemia is defined by the presence of immunoglobulins having the following characteristics: forming a gel when temperature is <37 °C, precipitate in a reversible manner in the serum, and redissolve after rewarming. The presence of both polyclonal IgG and monoclonal IgM (type II), or of polyclonal IgG and polyclonal IgM (type III) identifies the mixed cryoglobulinemia (MC). The identification of the Hepatitis C virus (HCV) infection in most of the cases previously defined as "essential" represented a cornerstone in the understanding the pathogenesis of this condition. The picture of MC comprehends heterogeneous clinical presentations: from arthralgias, mild palpable purpura, fatigue to severe vasculitis features with skin necrotic pattern, peripheral neuropathy and, less commonly, lungs, central nervous system, gastrointestinal tract, and heart involvement. The kidney represents the most common organ presentation, and the presence of glomerulonephritis is a key element when considering prognosis. We discuss the clinical presentation and histological features, diagnostic pitfalls, and controversies in the management of patients with cryoglobulinemic glomerulonephritis, with a special focus on reporting our experience in treating patients with B cell depletion therapy.

[Hepatic tropism of hepatitis C virus infection]

Hepatitis C virus (HCV) infects over 170 million people worldwide and is a major cause of life-threatening liver diseases such as liver cirrhosis and hepatocellular carcinoma. In current research, we aimed to clarify the mechanism of hepatic tropism of HCV infection. Although non-hepatic cells could not permit replication of HCV RNA, exogenous expression of liver specific miRNA, miR-122 facilitated efficient replication of viral RNA through direct interaction with 5'UTR of viral genome, indicating that miR-122 is one of the key determinants for hepatic tropism of HCV infection. In spite of efficient replication of viral RNA, formation of infectious particles was not observed in non-hepatic cells exogenously expressing miR-122. We found that expression of apolipoprotein E (ApoE) facilitated the formation of infectious HCV particles in non-hepatic cells, indicating that not only miR-122 but also ApoE participate in tissue tropism of HCV infection. To understand the exact roles of miR-122 and apolipoproteins in hepatic tropism of HCV, we established miR-122 and ApoB/ApoE knockout (KO) Huh7 cells, respectively. Although slight increase of intracellular HCV RNA and infectious titers in the culture supernatants was observed, propagation of HCV was impaired in miR-122 KO Huh7 cells. After serial passages of HCV in miR-122 KO cells, we obtained an adaptive mutant that possessed G28A substitutions in the 5'UTR of the HCV genome and exhibited efficient translation and replication in both miR-122 KO Huh7 and non-hepatic cells without exogenous expression of miR-122. These results suggest that HCV mutants replicating in non-hepatic cells in an miR-122-independent manner participate in the induction of extrahepatic manifestations in chronic hepatitis C patients. Deficiency of both ApoB and ApoE strongly inhibited the formation of infectious HCV particles. Interestingly, expression not only of ApoE but also of ApoA or ApoC could rescue the production of infectious HCV particles in ApoB/ApoE KO cells, suggesting that exchangeable apolipoproteins redundantly participate in the formation of infectious HCV particles.

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.

Treatment for cryoglobulinemic and non-cryoglobulinemic peripheral neuropathy associated with hepatitis C virus infection

BACKGROUND

Peripheral neuropathy is the most common neurologic complication of hepatitis C virus (HCV) infection. The pathophysiology of the neuropathy associated with HCV is not definitively known; however, proposed mechanisms include cryoglobulin deposition in the vasa nervorum and HCV-mediated vasculitis. The optimal treatment for HCV-related peripheral neuropathy has not been established.

OBJECTIVES

To assess the effects of interventions (including interferon alfa, interferon alfa plus ribavirin, corticosteroids, cyclophosphamide, plasma exchange, and rituximab) for cryoglobulinemic or non-cryoglobulinemic peripheral neuropathy associated with HCV infection.

SEARCH METHODS

On 26 August 2014, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, and EMBASE. We also searched two trials registers, the Networked Digital Library of Theses and Dissertations (NDLTD) (October 2014), and three other databases. We checked references in identified trials and requested information from trial authors to identify any additional published or unpublished data.

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) and quasi-RCTs involving participants with cryoglobulinemic or non-cryoglobulinemic peripheral neuropathy associated with HCV infection. We considered any intervention (including interferon alfa, interferon alfa plus ribavirin, corticosteroids, cyclophosphamide, plasma exchange, and rituximab) alone or in combination versus placebo or another intervention ('head-to-head' comparison study design) evaluated after a minimum interval to follow-up of at least six months.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration. The planned primary outcome was change in sensory impairment (using any validated sensory neuropathy scale or quantitative sensory testing) at the end of the follow-up period.  Other planned outcomes were: change in impairment (any validated combined sensory and motor neuropathy scale), change in disability (any validated disability scale), electrodiagnostic measures, number of participants with improved symptoms of neuropathy (global impression of change), and severe adverse events.

MAIN RESULTS

Four trials of HCV-related cryoglobulinemia fulfiled selection criteria and the review authors included three in quantitative synthesis. All studies were at high risk of bias. No trial addressed the primary outcome of change in sensory impairment. No trial addressed secondary outcomes of change in combined sensory and motor impairment, disability, or electrodiagnostic measures. A single trial of HCV-related mixed cryoglobulinemia treated with pegylated interferon alfa (peginterferon alfa), ribavirin, and rituximab versus peginterferon alfa and ribavirin did not show a significant difference in the number of participants with improvement in neuropathy at 36 months post treatment (risk ratio (RR) 4.00, 95% confidence interval (CI) 0.27 to 59.31, n = 9). One study of interferon alfa (n = 22) and two studies of rituximab (n = 61) provided adverse event data. Severe adverse events were no more common with interferon alfa (RR 7.00, 95% CI 0.38 to 128.02) or rituximab (RR 3.00, 95% CI 0.13 to 67.06) compared to the control group.

AUTHORS' CONCLUSIONS

There is a lack of RCTs and quasi-RCTs addressing the effects of interventions for peripheral neuropathy associated with HCV infection. At present, there is insufficient evidence from RCTs and quasi-RCTs to make evidence-based decisions about treatment.

Mixed cryoglobulinemia: an unusual presentation of hepatitis C

A 50-year-old man with a history of hepatitis C presented with recurrent episodes of abdominal pain, arthralgia, and weakness. Although these symptoms seemed rather non-specific, a purpuric rash of the lower extremities was the final clue to diagnosis. The diagnosis was then confirmed by histopathologic and serologic testing.

Antiviral therapy of symptomatic HCV-associated mixed cryoglobulinemia: meta-analysis of clinical studies

Hepatitis C virus (HCV) infection may be associated with extra-hepatic illness including mixed cryoglobulinemia. Evidence on HCV-related mixed cryoglobulinemia in the non-transplantation setting exists even if its appropriate management remains unclear. The cornerstone of treatment for symptomatic HCV-associated mixed cryoglobulinemia is antiviral therapy but little is known about its activity. A systematic review of the literature with a meta-analysis of clinical studies was performed in order to assess efficacy and safety of combination antiviral therapy for symptomatic HCV-associated mixed cryoglobulinemia in non-immunosuppressed individuals. The random effects model of DerSimonian and Laird was used, with heterogeneity and sensitivity analyses. The primary outcome was sustained virological response (as a measure of efficacy), and the secondary outcome was the rate of patients stopping (or dose reducing) antiviral agents (as a measure of tolerability). Ten clinical studies (300 unique patients) were identified; the rate of baseline kidney involvement ranged between 4% and 39%. The summary estimate of frequency of sustained viral response was 0.42 with a 95% confidence interval (CI) of 0.31; 0.54 (random effects model). Significant heterogeneity occurred (P = 0.00001; I(2) = 77.6%). Stratified analysis showed higher efficacy in those studies using combination therapy with pegylated-than conventional IFN; the summary estimate of sustained viral response being 0.52 (95% CI, 0.40; 0.63) and 0.32 (95% CI, 0.15; 0.49), respectively. There was good association between viral and clinical response, weighted K 0.634 (95% CI, 0.455; 0.814), by a meta-analysis at individual level on a subset of reports (n = 3; 74 unique patients). The summary estimate of frequency of patients stopping (or dose reducing) antiviral agents was 0.15 (95% CI, 0.08; 0.21); no heterogeneity occurred (P = 0.05; I(2) = 51%). In summary, combination antiviral therapy (pegylated IFN plus ribavirin) gives satisfactory response in more than the half of patients with symptomatic mixed cryoglobulinemia associated with HCV. HCV-related mixed cryoglobulinemia is uncommon in developed countries and this clearly hampers randomized controlled clinical trials aimed to evaluate efficacy and safety of antiviral therapy in non-immunosuppressed individuals.

[miR-122 participates in the cell tropism of hepatitis C virus]

Hepatitis C virus (HCV) exhibits a narrow host range and a specific tissue tropism. Studies on HCV life cycle have been progressed by the developments of in vitro replication and infection systems and an HCV laboratory strain (HCVcc) capable of propagating in human hepatoma cell line, Huh7 cells. Mice expressing four human entry receptor candidates for HCV permit entry of HCVcc, therefore tissue tropism of HCV was believed to be rely on the expression of the entry receptors. However, HCV infection is often associated with extra-hepatic manifestations and the determinants for cell tropism of HCV remain elusive. Recently, we have shown that several nonhepatic cell lines permit HCV-RNA replication through an expression of a liver-specific microRNA, miR-122, upon infection with HCVcc, while no infectious particle was produced. In the nonhepatic cells, only small numbers of lipid droplets and low levels of VLDL-associated proteins were observed in compared with Huh7 cells, suggesting that expression of miR-122 and functional lipid metabolism participates in the replication and assembly of HCVcc, respectively In this review, we would like to discuss about involvement of miR-122 and functional lipid metabolism in the determination of HCV cell tropism.

Role of miR-122 and lipid metabolism in HCV infection

Hepatitis C virus (HCV) exhibits a narrow host range and a specific tissue tropism. Mice expressing major entry receptors for HCV permit viral entry, and therefore the species tropism of HCV infection is considered to be reliant on the expression of the entry receptors. However, HCV receptor candidates are expressed and replication of HCV-RNA can be detected in several nonhepatic cell lines, suggesting that nonhepatic cells are also susceptible to HCV infection. Recently it was shown that the exogenous expression of a liver-specific microRNA, miR-122, facilitated the efficient replication of HCV not only in hepatic cell lines, including Hep3B and HepG2 cells, but also in nonhepatic cell lines, including Hec1B and HEK-293T cells, suggesting that miR-122 is required for the efficient replication of HCV in cultured cells. However, no infectious particle was detected in the nonhepatic cell lines, in spite of the efficient replication of HCV-RNA. In the nonhepatic cells, only small numbers of lipid droplets and low levels of very-low-density lipoprotein-associated proteins were observed compared with findings in the hepatic cell lines, suggesting that functional lipid metabolism participates in the assembly of HCV. Taken together, these findings indicate that miR-122 and functional lipid metabolism are involved in the tissue tropism of HCV infection. In this review, we would like to focus on the role of miR-122 and lipid metabolism in the cell tropism of HCV.

Treatment of hepatitis C cryoglobulinemia: mission and challenges

Mixed cryoglobulinemia (MC) is a syndrome resulting from cold-insoluble immunoglobulin complexes or cryoglobulins (CGs) that precipitate in the serum of 40% to 50% of patients with chronic hepatitis C virus (HCV) infection. The pathogenesis of cryoglobulinemia likely occurs due to chronic viremia and generation of rheumatoid factor following continuous presentation of antigen-immunoglobulin complexes to B cells. CGs are thought to be responsible for a variety of extrahepatic manifestations associated with HCV, including vasculitis, glomerulonephritis, arthritis, and neuropathies, which occur in approximately 10% of HCV patients with CGs. CGs also are a powerful predictive factor for progressive liver disease and the aggressive reoccurrence of liver disease in HCV-positive patients after liver transplantation. First-line therapy for MC due to HCV infection is antiviral therapy with pegylated interferon-alpha and ribavirin. Viral eradication usually produces marked reduction of physical complications and arrests end organ damage concomitant with clearance of CG. Additional prospective, controlled studies are necessary to determine whether CG influences patient virologic response and/or its durability to antiviral therapy. Immunomodulators such as corticosteroids and cyclophosphamide are efficacious for palliative treatment of the symptomatology of HCV cryoglobulinemia but may enhance viral replication. Consequently, prolonged therapy with immunomodulatory agents should be limited to severe vasculitis or aggressive glomerulonephritis in patients with MC due to HCV who have failed to respond to antiviral therapy. In acute, fulminant presentations, plasmapheresis may provide temporary relief and arrest the rapid progression of the disease so that additional therapy can be initiated.

Autoimmune manifestations in viral hepatitis

Infections by the viruses responsible for hepatitis B, C and D are accompanied by a number of immunopathological manifestations. A link between infection and autoimmunity is particularly well documented for the hepatitis C virus. Immunopathological manifestations range from production of autoantibodies to overt autoimmune disease, including thyroiditis and autoimmune hepatitis, and to immune-complex-mediated disorders, including cryoglobulinaemia, glomerulonephritis and vasculitis. Several of these manifestations improve with successful antiviral treatment, directly incriminating the virus in their pathogenesis. Mechanisms considered responsible for hepatitis virus-related immunopathology, including molecular mimicry, impairment of regulatory T cells and activation of B lymphocytes, will be examined in this review.

Expression of microRNA miR-122 facilitates an efficient replication in nonhepatic cells upon infection with hepatitis C virus

Hepatitis C virus (HCV) is one of the most common etiologic agents of chronic liver diseases, including liver cirrhosis and hepatocellular carcinoma. In addition, HCV infection is often associated with extrahepatic manifestations (EHM), including mixed cryoglobulinemia and non-Hodgkin's lymphoma. However, the mechanisms of cell tropism of HCV and HCV-induced EHM remain elusive, because in vitro propagation of HCV has been limited in the combination of cell culture-adapted HCV (HCVcc) and several hepatic cell lines. Recently, a liver-specific microRNA called miR-122 was shown to facilitate the efficient propagation of HCVcc in several hepatic cell lines. In this study, we evaluated the importance of miR-122 on the replication of HCV in nonhepatic cells. Among the nonhepatic cell lines expressing functional HCV entry receptors, Hec1B cells derived from human uterus exhibited a low level of replication of the HCV genome upon infection with HCVcc. Exogenous expression of miR-122 in several cells facilitates efficient viral replication but not production of infectious particles, probably due to the lack of hepatocytic lipid metabolism. Furthermore, expression of mutant miR-122 carrying a substitution in a seed domain was required for efficient replication of mutant HCVcc carrying complementary substitutions in miR-122-binding sites, suggesting that specific interaction between miR-122 and HCV RNA is essential for the enhancement of viral replication. In conclusion, although miR-122 facilitates efficient viral replication in nonhepatic cells, factors other than miR-122, which are most likely specific to hepatocytes, are required for HCV assembly.

Hepatitis C and kidney disease

Multiple extrahepatic manifestations have been associated with chronic hepatitis C, the most important among them being cryoglobulinemia, glomerulonephritis, porphyria cutanea tarda, lichen planus, seronegative arthritis, and lymphoproliferative disorders as in the sudies of Bonkovsky and Mehta (2001) and El-Serag et al. (2002). We will discuss in this paper chronic hepatitis C- related kidney disease and course and management of patients with chronic hepatitis C in special circumstances like hemodialysis and kidney transplantation.

Pegylated interferon-α, ribavirin, and rituximab combined therapy of hepatitis C virus–related mixed cryoglobulinemia: a long-term study

This study illustrates the use and efficacy of a combination of pegylated interferon-α (Peg-IFN-α) and ribavirin (RBV), with or without rituximab (RTX), in hepatitis C virus (HCV)–related mixed cryoglobulinemia (MC). Twenty-two patients with HCV-related MC received Peg-IFN-α (2a: 180 μg or 2b: 1.5 μg/kg) weekly plus RBV (1000 or 1200 mg) daily for 48 weeks, and RTX (375 mg/m2) once a week for 1 month followed by two 5-monthly infusions (termed PIRR). Fifteen additional patients received Peg-IFN-α/RBV with the same modalities as the PIRR schedule. Complete response was achieved in 54.5% (12/22) and in 33.3% (5/15) of patients who received PIRR and Peg-IFN-α/RBV, respectively (P < .05). Clearance of HCV RNA and conversion of B-cell populations from oligoclonal to polyclonal in liver, bone marrow, and peripheral blood was maintained for up to 3 years in 10 of 12 (83.3%) and in 2 of 5 (40%) patients receiving PIRR and Peg-IFN-α/RBV, respectively (P < .01). Cryoproteins in 22.7% (5/22) of patients with PIRR and in 33.3% (5/15) with Peg-IFN-α/RBV persisted despite sustained HCV RNA clearance. No response occurred in remaining 5 patients of both groups. PIRR therapy is well tolerated and more effective than Peg-IFN-α/RBV combination in HCV-related MC. Its effect may last for more than 3 years.

Long-term outcomes after treatment with interferon and ribavirin in HCV patients

Hepatitis C is a leading indication for transplantation and a common cause of liver-related death worldwide. Treatment for hepatitis C has evolved from interferon therapy alone, which yielded relatively poor response rates compared with the currently recommended and more effective combination of pegylated interferon and ribavirin. Factors such as hepatitis C viral genotype, pretreatment viral load, race, renal function, degree of hepatic fibrosis, and comorbid conditions such as HIV coinfection have clinical importance in that they influence viral kinetics, which play a large role in determining a sustained response to therapy or virologic "cure." However, the goal of therapy is to reduce liver-related morbidity and mortality by decreasing rates of progression or improvement of fibrosis, reducing risk of hepatocellular carcinoma, improving posttransplant graft and patient survival, and resolving or improving some of the extrahepatic manifestations of hepatitis C. Studies generally infer long-term success from the more tangible goal of sustained viral suppression; however, increasing data suggest that effective therapy does result in decreased morbidity and mortality. Given the heterogeneity of patients who are infected with hepatitis C, treatment decisions should be specifically tailored to each individual patient on the basis of their predisposing conditions and anticipated clinical outcomes.

Extrahepatic hepatitis C virus after transplantation: diabetes and renal dysfunction

1. Insulin resistance is associated with hepatitis C virus infection and plays a role in the progression of hepatitis C virus-related liver disease and fibrosis. 2. Treating insulin resistance and achieving glycemic control will be important for improving post-liver transplant morbidity and mortality: control of the hepatitis C virus will help to accomplish this. 3. The main renal complication of hepatitis C virus is membranoproliferative glomerulonephritis, and this occurs most commonly in the setting of mixed cryoglobulinemia.

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.

Infection and glomerulonephritis

Glomerular injury, occurring either as primary glomerular disease or as part of a systemic disease process, is usually a result of immune-mediated mechanisms. The morphologic reaction pattern has a diverse spectrum of appearance, ranging from normal by light microscopy in minimal change disease to crescentic forms of glomerulonephritis, with conspicuous disruption of the normal glomerular morphology. The mechanisms of glomerular immune deposit formation include trapping of circulating antigen-antibody complexes and the in situ formation of immune complexes within the glomerulus. While the majority of postinfectious immune-complex-mediated glomerulonephritides are believed to result from the deposition of circulating antigen-antibody complexes, preformed outside of the kidney and secondarily deposited in the kidney, the notion of forming in situ antigen-antibody complexes to either planted antigens or to integral structural components of the glomerulus, through "cross-reacting" autoimmune reactions, is gaining popularity in a variety of forms of glomerulonephritides. Patients with HIV infection may develop a spectrum of renal pathology, the glomerular manifestations of which include both antigen-antibody complex and nonimmune-complex-mediated pathogenetic mechanisms. Similarly, patients with Streptococcal infections, Hepatitis B virus, or Hepatitis C virus infection may develop a spectrum of glomerulonephritides, which are predominantly immune-complex-mediated. Therapy for glomerular diseases due to HIV, hepatitis B, or C virus infections remains a challenge.

Symptomatic and virological response to antiviral therapy in hepatitis C associated with extrahepatic complications of cryoglobulimia

Mixed cryoglobulins are detected in 50% of patients with hepatitis C; fortunately, few have vasculitis affecting skin, peripheral nerves, kidneys, and synovia. This study was designed to identify the natural history of symptomatic cryoglobulinemia and evaluate the response to antiviral therapy. Patients with hepatitis C complicated by symptomatic cryoglobulinemia were assessed for their disease manifestations and response to antiviral therapy. Of 83 patients identified, 56 patients with a minimum of 12 months follow-up were reviewed. Manifestations included dermatologic (75%), rheumatologic (57%), neurologic (34%), and renal (proteinuria 25%). Antiviral therapy was given to 38, of whom 9 were retreated for symptomatic and/or virological nonresponse. Antiviral therapy included interferon monotherapy (n= 8), pegylated-interferon monotherapy (n= 5), consensus-interferon (n= 2), interferon + ribavirin (n= 18), and pegylated-interferon + ribavirin (n= 14). Treatment provided sustained symptomatic response in 31 (82%) and virological response in 16 (42%) patients. Symptomatic cryoglobulinemia responds well to antiviral therapy, even when virological response is not achieved.

Etiologic treatment of hepatitis C virus-associated mixed cryoglobulinemia

The treatment of mixed cryoglobulinemia (MC) includes several drugs--steroids, cyclosporins, colchicine, plasmapheresis--but given the documented association between MC and hepatitis C virus (HCV), the treatment of choice seems to be antiviral therapy. Several authors have reported the efficacy of interferon (IFN) alpha in the inhibition of HCV replication and reduction of cryoglobulin levels. The therapy with IFN as monotherapy in MC shows a complete response rate in only 10 -12% of cases. Complete response to therapy using a combination of IFN plus ribavirin varies in different studies from 18% to 64% of cases. There are only two studies on the treatment of MC with peginterferon plus ribavirin. Both studies, given the high number of complete responders, reinforce the idea that peginterferon plus ribavirin is, at present, the best available treatment for cryoglobulinemic syndrome. The results obtained with peginterferon combined therapy are superior to standard interferon plus ribavirin in treatment-naive patients. In fact, a sustained virological response was observed in 44% of patients; the same results were obtained for clinical (purpura and arthralgia disappearance) and biochemical (aminotransaminases normalization) responses. New drug combinations, like peginterferons plus anti-CD20 antibodies, should be considered for treatment of MC in the future.

Cryoglobulinemia

Cryoglobulinemia refers to the presence in serum of immunoglobulins that precipitate at a cold temperature. Type I cryoglobulins are single monoclonal immunoglobulins usually associated with haematological disorders. Types II and III are mixed cryoglobulins, composed of monoclonal or polyclonal IgM respectively, having rheumatoid factor activity that bind to polyclonal immunoglobulins. Mixed cryoglobulinemia (MC) syndrome is a consequence of immune-complex mediated vasculitis and is characterized by a typical clinical triad: purpura, weakness, arthralgias; many organs particularly kidney and peripheral nervous system may be involved. MC may be associated with infectious and systemic disorders and since 1990 studies have demonstrated that hepatitis C virus (HCV) may be considered the principal trigger of the disease. The relation between MC and HCV infection shows new insights in the interpretation of the link between viral infection, autoimmune phenomena and lymphoproliferative disorders evolution. In fact, the virus chronically stimulates B-cell polyclonal proliferation from which a monoclonal population may emerge. In symptomatic patients with HCV related MC therapeutic strategy should include an attempt at viral eradication. Antiviral therapy may also be effective in determining the regression of B-cell lymphoproliferative disorder. Rituximab could represent a safe and effective alternative to standard immunosuppression and exerts selective B-cell control.

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.

Cryoglobulinemia in chronic hepatitis C: clinical aspects and response to treatment with interferon alpha and ribavirin

INTRODUCTION: The main extra-hepatic manifestation of hepatitis C is mixed cryoglobulinemia (MC). The aim of this study was to evaluate its prevalence among patients with chronic hepatitis C (CHC), to correlate its presence to host and virological variables and to the response to combined therapy with interferon-alpha and ribavirin. CASUISTIC AND METHODS: 202 CHC naive patients (136 with chronic hepatitis and 66 with cirrhosis) were consecutively evaluated for the presence of cryoglobulins. Cryoprecipitates were characterized by immunoelectrophoresis and classified according to the Brouet's criteria. RESULTS: The prevalence of MC was 27% (54/202), and 24% of them (13/54) showed major clinical manifestation of the disease. Even though type III MC was more frequent (78%), symptomatic MC was more common in type II MC. The presence of cirrhosis (RR = 2.073; IC95% = 1.029 - 4.179; p = 0.041), and age of the patients (RR = 1.035; IC95% = 1.008 - 1.062; p = 0.01) were independently associated with the presence of cryoglobulins. No relationship was found with viral load and genotype. 102 patients were treated with interferon alpha and ribavirin. Among these, 31 had MC. Sustained virological response (around 30%) was similar in patients with and without MC (p = 0.971). CONCLUSION: MC represents a prevalent complication in patients with CHC, specially older and cirrhotic patients. Only 24% of these patients show clinical manifestation of the disease, specially those with type II MC. The presence of MC did not affect the response to therapy.

Dermatologic disorders associated with chronic hepatitis C: effect of interferon therapy

Chronic hepatitis C virus infection (HCV) is associated with extrahepatic manifestations, including such dermatologic conditions as mixed cryoglobulinemia, porphyria cutanea tarda, and lichen planus. Patients with chronic HCV and extrahepatic manifestations are often excluded from clinical trials evaluating interferon (IFN) therapy due to concerns about poor response, adverse events, and toxicity. Thus, data regarding the efficacy of IFN not only on the underlying chronic HCV, but also on extrahepatic manifestations, are limited in these patients. Case reports suggest that the response of dermatologic extrahepatic manifestations to IFN in patients with chronic HCV is highly variable. This review summarizes available data on dermatologic conditions associated with chronic HCV and their response to IFN therapy.

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.

Newer Therapeutic Approaches to the Vasculitides: Biologic Agents

Biologic therapies have emerged as important treatments in chronic inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease, and are now garnering more attention in the vasculitides. These agents, including tumor necrosis factor-alpha inhibitors, B-cell-depleting agents, interferon-alpha, and some antiviral treatments, target specific components of the immune system and may have lower side effect risk profiles than the conventional immunosuppressives and cytotoxic agents. This article addresses the encouraging data and the possible pitfalls of these new therapeutic options, thus far evaluated mostly by case reports, small series, and open-label trials. Confirming the efficacy of existing and newer therapies will require further clinical investigation through randomized placebo-controlled studies to identify the proper doses and treatment schedules and single out those drugs that may expose patients to dangers that outweigh the potential benefits.

Effects of combined antiviral therapy on asymptomatic mixed cryoglobulinemia in naive patients with chronic hepatitis C virus infection: a preliminary study

The clinical spectrum of mixed cryoglobulinemia embraces several manifestations: recurrent vascular purpura, weakness, arthralgia/arthritis, glomerulonephritis, peripheral neuropathies, and Raynaud's phenomenon. Mixed cryoglobulinemia is currently treated with steroids, low-antigen content diet, immunosuppressors, plasma exchange, and antiviral therapy, namely, alpha -interferon alone or, more recently, in association with ribavirin. In the present research, we verified the effectiveness of combined therapy with interferon and ribavirin on asymptomatic mixed cryoglobulinemia in naïve (never treated before) patients with chronic hepatitis C. We enrolled 50 consecutive patients, 31 males and 19 females, with chronic hepatitis C who showed a sustained response to combined antiviral therapy (interferon and ribavirin). Before treatment, cryoglobulins were detected in 25 subjects (50%). Only 1 of the 25 patients with asymptomatic mixed cryoglobulinemia had persistence of cryoglobulins at the end of the follow-up period. Unexpectedly, in 7 of 25 subjects without mixed cryoglobulinemia before treatment, cryoglobulins became detectable after antiviral therapy. Our present study first reports the onset of asymptomatic mixed cryoglobulinemia in hepatitis C virus patients after clearance of the virus from blood obtained with a combined antiviral treatment. Possible explanations are discussed. Our data also suggest that the appearance of a clinically evident mixed cryoglobulinemia cannot be excluded in this kind of subject.

Neurological aspects of multiple myeloma and related disorders

The spectrum of neurologic complications of multiple myeloma (MM) and related conditions is as diverse as the conditions themselves. Complications range from direct compression (radiculopathy, spinal cord compression, base-of-the-skull tumor) to the infiltrative (amyloid, peripheral neuropathies, and numb chin syndrome of myeloma), the metabolic (slowed mentation from hyperviscosity, hypercalcemia, or uremia), and to autoimmune or cytokine-mediated (peripheral neuropathy). The two most common presentations are the compressive radiculopathy one sees in multiple myeloma and the peripheral neuropathies associated with many of the other disorders. The authors will review the neurologic complications of MM, monoclonal gammopathy of undetermined significance (MGUS), Waldenström macroglobulinemia (WM), POEMS syndrome, amyloidosis, and cryoglobulinemia.

Treatment with peg-interferon alfa-2b and ribavirin of hepatitis C virus-associated mixed cryoglobulinemia: a pilot study

BACKGROUND/AIMS

The aim of this study is to verify the efficacy and safety of peg-interferon alfa-2b in combination with ribavirin for initial treatment of HCV-associated mixed cryoglobulinemia.

METHODS

Eighteen patients (7 women and 11 men) affected by mixed cryoglobulinemia were included in the study and treated with peg-interferon alfa-2b 1.0 microg/kg once a week plus ribavirin (1000 mg daily) for 48 weeks, regardless of the HCV genotype.

RESULTS

At the end of the treatment HCV-RNA became undetectable in 15 patients (83%) and most patients improved clinically. One subject suspended treatment at 13th week due to depression. A large fraction of the patients (8 cases: 44%) relapsed both virologically and clinically a few weeks after the end of therapy. At the end of follow-up, only eight patients (44%) obtained a sustained virological response.

CONCLUSIONS

Peg-interferon alfa-2b in combination with ribavirin seems safe and useful for patients affected by mixed cryoglobulinemia, but not as effective as in patients with HCV-positive chronic hepatitis without cryoglobulinemia.

Systematic review: regression of lymphoproliferative disorders after treatment for hepatitis C infection

AIM

To systematically review the experience of therapeutic studies where alpha-interferon with or without ribavirin was administered to patients with lymphoproliferative disorders, in order to evaluate whether eradication of hepatitis C virus may induce regression of lymphoproliferative disorders.

METHODS

We used bibliographical searches in electronic databases and in the Cochrane Library to determine our results.

RESULTS

Sixteen studies where an anti-viral regimen was administered to 65 hepatitis C virus-infected patients with lymphoproliferative disorders were identified. Complete remission of the lymphoproliferative disorder was achieved in 75% of the cases. In contrast, hepatitis C virus-negative subjects did not respond to interferon, indicating that the response in the hepatitis C virus-infected patients is not merely due to the antiproliferative effect of interferon. Remission after HCV eradication was maintained, provided that infection did not reappear. In hepatitis C virus-infected patients with non-Hodgkin's lymphoma treated with corticosteroids/chemotherapy liver function tests deterioration did not occur. The addition of interferon to standard chemotherapy may decrease hepatic side-effects of chemotherapy.

CONCLUSIONS

Although it is evident that larger therapeutical trials of anti-viral therapy are needed to determine the role of this strategy in hepatitis C virus-infected patients with lymphoproliferative disorders, encouraging data emerge from recent studies showing that interferon (plus ribavirin) is an attractive therapeutic option for some hepatitis C virus-related low-grade lymphomas.

Cold Agglutinin Disease and Cryoglobulinemia

Cold agglutinin disease is a form of direct, extravascular, antiglobulin-positive hemolysis. In vivo, immunoglobulin (Ig) M fixes complement molecules to the red cell membrane. Successive passages through the mononuclear phagocyte system result in loss of red cell membrane. The resultant spherocytes lose resiliency and are ultimately lost from the circulation extravascularly. The high concentration of complement molecules on the red cell surfaces makes this syndrome resistant to the standard therapies for immune-mediated hemolysis. Rituximab has been reported to reduce the severity of hemolysis. Type II cryoglobulins are composed of a monoclonal IgM and a polyclonal IgG. These complexes have rheumatoid factor activity and can produce immune-complex vasculitis. The target organs are the skin, nerves, kidney, liver, and joints. More than 80% of patients have evidence of hepatitis C infection. Interferon and interferon plus ribavirin have been shown to produce serologic responses. When vasculitis is active, corticosteroids are often required to permit healing of ulcers in the skin or to treat the membranoproliferative glomerulonephritis that is seen, thereby preventing loss of renal function. Rituximab therapy has been found to be effective in mixed cryoglobulinemia, with decreases in cryoglobulin values and improvement in complement values.

[Vasculitis associated with viral infections]

VIRUSES, THE CAUSE OF VASCULITIS: Although the majority of systemic vasculitis are of unknown causes, the responsibility of a viral infection has been formally demonstrated in some of them and specific treatment can permanently cure them. Each virus incriminated accounts for a particular type of vasculitis. HEPATITIS B VIRAL INFECTION (HBV): Is the cause of polyarteritis nodosa in 36 to 50% of cases. The onset of the symptomatology is acute, usually within a few months following the infection; it is comparable to that observed in the absence of HBV infection. CRYOGLOBULINEMIA RELATED TO THE HEPATITIS C VIRUS (HCV): The clinical manifestations are those of systemic vasculitis with particular tropism for the skin (involvement generally inaugural and almost constant), peripheral nerves and the glomerula. They occur fairly late during the infection. VASCULITIS ASSOCIATED WITH HIV INFECTION: There is strong tropism for the peripheral (multi-neuritis) and central nervous system. During acute parvovirus B19 infection Vasculitis lesions have occasionally been reported following the viremic phase, generally limited to one or several flares of vascular purpura predominating on the lower limbs. FOLLOWING VARICELLA-HERPES ZOSTER INFECTION: Vasculitis occasionally develops in the form of a central neurological deficiency (locomotor deficiency with or without aphasia around one month after an ophthalmologic herpes zoster) or involving the retina or, more rarely, the skin or the kidneys. VASCULITIS ASSOCIATED WITH CYTOMEGALOVIRAL INFECTION: Predominantly observed in immunodepressed patients, vasculitis after CMV infection is diffuse and basically involving the digestive tube, notably the colon, the central nervous system and the skin. A RARE COMPLICATION OF AN HTLV1 INFECTION: Vasculitis of the retina often in the form of necrotic retinitis is often associated with spasmodic paraparessia.

THERAPEUTIC STRATEGY

For many vasculitis of viral origin, corticosteroid and immunosuppressive treatments are only indicated in second intention following failure with antiviral agents and the combination of antivirals and plasma exchanges.

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.

Antiviral therapy: role in the management of extrahepatic diseases

This article considers the extrahepatic manifestations associated with HBV and HCV infection, the strength of the evidence for the association, potential pathological mechanisms, and evidence based therapeutic recommendations. As many of these extra hepatic conditions are uncommon, published reports have been largely uncontrolled or anecdotal.

Hepatitis C virus-related extra-hepatic disease--aetiopathogenesis and management

Summary Hepatitis C virus infection is often associated with extra-hepatic manifestations, secondary to the elicitation of autoimmune reactions, generalized deposition of immune complexes and lymphoproliferative disorders. The most clearly established associations are those linking chronic hepatitis C with mixed cryoglobulinaemia (and the related glomerulonephritis and cutaneous vasculitis), as well as with the presence of autoantibodies. Less well-documented disorders include non-Hodgkin's lymphoma, thrombocytopenia, sialadenitis, thyroid disease, lichen planus, porphyria cutanea tarda, rheumatoid disorders and neurological disorders. Extra-hepatic manifestations are most frequent in patients of female sex, advanced age, long-lasting infection and cirrhosis. Optimal treatment strategies should be based on the predominant manifestation of the disease. In the case of autoimmune disorders not clearly attributable to the viral infection, corticosteroids may be the most effective option. Interferon-alpha alone or in combination with ribavirin may be indicated for those disorders related to immune complex deposition, such as mixed cryoglobulinaemia, although relapses of extra-hepatic signs often occur on discontinuation of treatment. In some cases, interferon-alpha may induce or exacerbate some extra-hepatic manifestations.

Hepatitis C and renal disease: an update

Hepatitis C is both a cause and a complication of chronic renal disease. Chronic infection with hepatitis C virus (HCV) can lead to the immune complex syndromes of cryoglobulinemia and membranoproliferative glomerulonephritis (MPGN). The pathogenetic mechanisms for these conditions have not been defined, although they are clearly caused by the chronic viral infection. Management of HCV-related cryoglobulinemia and MPGN is difficult; antiviral therapy is effective in clearing HCV infection in a proportion of patients, but these conditions can be severe and resistant to antiviral therapy. Hepatitis C also is a complicating factor among patients with end-stage renal disease and renal transplants. The source of HCV infection in these patients can be nosocomial. Screening and careful attention to infection control precautions are mandatory for dialysis units to prevent the spread of hepatitis C. Prevention of spread is particularly important in these patients because HCV infection is associated with significant worsening of survival on dialysis therapy, as well as after kidney transplantation. Furthermore, therapy for hepatitis C is problematic, only partially effective, and associated with significant side effects in this population. There are significant needs in both basic and clinical research in the pathogenesis, natural history, prevention, and therapy for hepatitis C in patients with renal disease.

Efficacy and safety of rituximab in type II mixed cryoglobulinemia

The best treatment of type II mixed cryoglobulinemia (MC) has still to be defined. Antiviral treatment for the frequent underlying infectious trigger hepatitis C virus (HCV) may be ineffective, contraindicated, or not tolerated in a fraction of cases, whereas current immunosuppressive treatments may lead to relevant complications. Selective B-cell blockade with rituximab was used in this study, based on favorable results in preliminary experience. Fifteen consecutive patients with type II MC (HCV-related in 12 of 15) were treated with rituximab, 375 mg/m(2) intravenously weekly for 4 weeks. Only medium- to low-dose steroids were allowed, if already administered at the time of recruitment. All patients had active disease, poorly controlled or difficult to manage with previous treatments, including corticosteroids in all. Efficacy and safety of rituximab therapy were evaluated in the following 6 months. The overall follow-up after rituximab treatment ranged from 9 to 31 months. Rituximab proved effective on skin vasculitis manifestations (ulcers, purpura, or urticaria), subjective symptoms of peripheral neuropathy, low-grade B-cell lymphoma, arthralgias, and fever. Nephritis of recent onset went into remission in one case. Laboratory features, that is, significantly decreased serum rheumatoid factor and cryoglobulins and increased C4, were consistent with the clinical efficacy. Treatment was well tolerated, with no infectious complications. Thrombosis of retinal artery or self-limiting panniculitis occurred in one patient each. Rituximab may represent a safe and effective alternative to standard immunosuppression in type II MC. Controlled studies are needed to better define drug indications and the cost-efficacy profile in the different systemic manifestations.

Cutaneous vasculitis

Vasculitis can range in severity from a self-limited single-organ disorder to a life-threatening disease with the prospect of multiple-organ failure. This condition presents many challenges to the physician, including classification and diagnosis, appropriate laboratory workup, treatment, and the need for careful follow-up. The physician must not only be able to recognize vasculitis but also be able to provide a specific diagnosis (if possible) as well as recognize and treat any underlying etiologic condition. Most diagnostic criteria are based on the size of vessel involvement, which often correlates with specific dermatologic findings. This may allow the dermatologist to provide an initial diagnosis and direct the medical evaluation. This article reviews the classification and diagnosis of cutaneous vasculitic syndromes and current treatment options; it also presents a comprehensive approach to diagnosing and treating the patient with suspected cutaneous vasculitis. (J Am Acad Dermatol 2003;48:311-40.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with the classification and clinical features of the various forms of cutaneous vasculitis. They should also have a rational approach to diagnosing and treating a patient with vasculitis.

Biologic therapies in the vasculitides

Monoclonal antibody and recombinant DNA technologies have led to the development of biologic therapies capable of directly targeting selected components of the immune response. With the steady expansion of knowledge regarding the mechanisms of vascular inflammation, the safety and efficacy of biologic agents in the vasculitic diseases are being increasingly investigated. By targeting specific effector mechanisms involved in the pathogenesis of vasculitis, these agents may provide a less toxic means of inducing remission and lessening relapse. However, the study of biologic therapies in the vasculitides must be approached with caution, as unanticipated effects on disease activity and disease-specific toxicities can occur. Studies to examine these agents must recognize the potential for active vasculitis to be organ- or life-threatening as well as the current existence of effective therapies. In the research setting, investigation of biologic agents in the treatment of vasculitic diseases may also provide important insights into pathogenesis of these syndromes.

Cryoglobulinemia: a true internistic disease?

Cryoglobulinemia is a clinical condition characterised by the presence of circulating globulins that precipitate at a temperature lower than 37 degrees Celsius and re-dissolve with warming. We can distinguish 3 different types of cryoglobulinemia, according to their immunochemical characteristics. Cryoglobulinemia can be associated with infectious, inflammatory or neoplastic disease. Cryoglobulinemia type II can be associated with chronic HCV-hepatitis. Clinically, cryoglobulinemias cause hyperviscosity-related symptoms or lesions by immunocomplex deposition (cryoglobulinemic vasculitis). Many organs and systems can be involved, from the skin to the joints, from the central nervous system to the kidney. Diagnosis requires a careful clinical and physical evaluation and the demonstration of circulating cryoglobulins by cryoprecipitation and immunoelectrophoresis. The therapeutic goals are the treatment of the underlying diseases and the complication and prevention of progression/relapse. It is obvious that this disorder can involve different specialists, but the internist plays a central role: he identifies the disease and the associated condition, he treats the underlying disorder and refers the patient to the specialists for the organ-specific manifestations.

Hepatitis C, cryoglobulinemia, and cirrhosis: a meta-analysis

Approximately 40% of patients with chronic hepatitis C virus (HCV) infection develop detectable serum cryoglobulins or cryoprecipitates (CP), although most do not show clinical or physical signs of syndromic cryoglobulinemia. Although association of HCV with the extrahepatic complications of cryoglobulinemia is widely recognized, the relationship of cryoglobulinemia with liver disease is unclear. We wished to study the relationship between CP and cirrhosis and to determine whether the development of CP is a true covariate for progressive liver disease or a confounding variable that impacts cirrhosis because of patient age, duration of disease, or differences in gender. We undertook a meta-analysis of 19 studies published between 1994 and 2001. The incidence of cirrhosis was compared in patients with and without CP after logistic regression adjustments for accepted risk factors for progressive liver disease, including age, gender, and estimated duration of disease (EDD). A total of 2,323 patients with chronic hepatitis C were identified, with 1,022 (44%) having detectable CP. Cirrhosis was present in 40% of patients with CP but only 17% of patients without CP (total Chi;(2) = 141.69, P <.001). After adjusting for age, gender, and estimated duration of disease by logistic regression, the combined odds ratio for incidence of cirrhosis in patients CP positive versus CP negative was 4.87, (95% CI: 3.32, 7.15), indicating a highly significant association between cirrhosis and cryoglobulinemia. In conclusion, cryoglobulins may be a useful prognostic indicator for increased risk of cirrhosis with chronic hepatitis C.

Treatment of chronic hepatitis C infection with cryoglobulinemia

Mixed cryoglobulinemia is characterized by a wide spectrum of manifestations that may vary from mild symptoms (such as purpura, arthralgias, and Raynaud phenomenon) to life-threatening conditions (such as acute abdomen, hyperviscosity syndrome, and renal involvement). Hepatitis C virus infection is considered the principal trigger of the disease. Therefore, the treatment not only should be tailored to the prevailing symptom but also take into account the presence of a chronic, often smoldering infection. Symptomatic therapies are to be used in cases of minor clinical manifestations and aggressive modalities in cases of life-threatening conditions. The use of aggressive cytotoxic regimens should actually be stopped and every potentially immunosuppressive drug should be used with caution. Antiviral medications are used with growing frequency. To date, a few small trials with interferon-alpha alone or in combination with ribavirin in mixed cryoglobulinemia have been conducted. This overview deals with the current approach to the management of mixed cryoglobulinemia, focusing in particular on antiviral treatment in hepatitis C virus infection with or without mixed cryoglobulinemia.

Cryoglobulinemia due to chronic viral hepatitis infections is not a major problem in clinical practice

Background: Essential mixed cryoglobulinemia (EMC) is a systemic disease frequently associated with chronic viral hepatitis. This study was conducted in order to assess the prevalence of EMC in patients with hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. We also evaluated the possible associations of EMC with (1) the clinical, virological, and histological status of liver disease; (2) the presence of EMC-related symptoms; and (3) the response rate to interferon-alpha (IFN-alpha) treatment, in an attempt to address whether EMC is a major problem in hepatitis patients. Methodology: A total of 154 consecutive patients (104 with HBV and 50 with HCV infection) were investigated for the presence of rheumatoid factor (RF), cryoglobulins, and EMC-related manifestations. Sixty-two HBV patients were chronic carriers of hepatitis B surface antigen, 29 had chronic hepatitis B, and 13 HBV cirrhosis. Thirty-five HCV patients had chronic hepatitis C and 15 HCV cirrhosis. HCV genotyping was performed in 44 patients. Results: The prevalence of cryoglobulins was significantly higher (P<0.001) in HCV patients (46%) than in HBV patients (13.4%). EMC was associated with a high frequency of RF detection, older age, and longer duration of viral diseases. Weakness or malaise, arthralgias, and purpura were significantly more frequent in cryoglobulin-positive patients. These manifestations, however, were mild in most of the patients. The EMC-related symptoms were significantly associated with the presence of HCV infection, increased levels of cryoglobulins, and RF detection (P<0.01, P<0.05, and P<0.000005, respectively). Worse liver histology was unrelated to a higher prevalence or increased levels of cryoglobulins in both HBV and HCV infection. There was no relationship between EMC and a specific HCV genotype. IFN-alpha therapy led to the disappearance of cryoglobulins and EMC-related manifestations in most cases. The response rate to IFN-alpha was similar in both groups of patients (with and without EMC). Conclusions: A higher prevalence of EMC was observed in HCV patients than in HBV patients. However, this finding was unrelated to overt clinical manifestations of EMC, a specific HCV genotype, or worse liver histology. The latter suggests that EMC does not contribute to liver injury and vice versa, that EMC pathogenesis is rather unrelated to the degree of liver injury. From a clinical point of view, testing for cryoglobulins seems reasonable only for HCV patients with EMC-related manifestations, since this may have therapeutic consequences. RF detection could be used primarily as a surrogate marker for the existence of cryoglobulins.

The benefit of long-term interferon alfa therapy for symptomatic mixed cryoglobulinemia (cutaneous vasculitis/membranoproliferative glomerulonephritis) associated with chronic hepatitis C infection

The efficacy of long-term interferon therapy for chronic hepatitis C infection with symptomatic mixed cryoglobulinemia has not clearly been defined. We describe a patient with chronic hepatitis C, symptomatic mixed cryoglobulinemia (cutaneous vasculitis), and membranoproliferative glomerulonephritis (MPGN) who responded clinically, biochemically, and virologically to a 1-year course of interferon therapy. Interferon side effects were minimal. Relapse occurred when interferon was discontinued, and suppressive maintenance interferon therapy was required for clinical, biochemical, and virologic remission. During the 5th year of maintenance therapy, she developed potential side effects that necessitated discontinuation of interferon treatment. After treatment stoppage, a clinical, biochemical, and virologic remission was maintained for more than 1 year. However, the potential side effects, which included eye irritation, arthralgias, myalgias, fatigue, insomnia, memory loss, and depression, persisted. Ophthalmologic, rheumatologic, and neurologic evaluations were nondiagnostic. Psychometric testing revealed dementia and mood disorder. Because the disabling symptoms persisted after 9 months, a health-related quality of life assessment was carried out with the SF-36 survey. Compared with healthy individuals and patients with chronic hepatitis C, our case had a lower health-related quality of life assessment on six out of seven scales and on four out of seven scales of the SF-36 survey, respectively. This case report indicates that long-term maintenance interferon therapy was effective in the treatment of symptomatic mixed cryoglobulinemia and its renal complications and resulted in a clinical, biochemical, and virologic sustained response. It is postulated that the side effects of long-term interferon therapy in this setting may be problematic.