[Hepatitis-C-virus-associated cryoglobulinemia. Pathogenesis, diagnosis and treatment]

BACKGROUND

Chronic hepatitis C-virus (HCV) infection is frequently associated with a variety of autoimmune phenomenons. Mixed cryoglobulins appear in up to 50% of chronic HCV-infected patients, mostly asymptomatic.

PATHOGENESIS

Cryoprecipitates present IgM with rheumatoid factor activity and development of immunocomplexes deposited in small vessels responsible for resulting vasculitis. MANIFESTATIONS: Characteristic clinical findings are weakness, arthralgia and purpura with further complications including glomerulonephritis and neuropathic lesions. Several mechanisms for HCV-induced clinical lymphoproliferation are discussed, such as chronic B-cell stimulation and activation of the antiapoptotic oncogene bcl-2 leading to immunoglobulin synthesis and eventually evolving into B-cell non-Hodgkin's lymphoma (NHL).

TREATMENT

Conventional treatment of HCV-associated mixed cryoglobulinemia aimes at reducing circulating immunocomplexes and causal therapy with interferon (IFN) and ribavirin. New approaches using the anti-CD20 antibody rituximab have been described recently.

Molecular study of an IgG1kappa cryoglobulin yielding organized microtubular deposits and glomerulonephritis in the course of chronic lymphocytic leukaemia

Glomerulonephritis with organized microtubular monoclonal immunoglobulin deposits (GOMMID) and glomerulonephritis related to type I cryoglobulin are well-known but rare complications of B cell derived chronic lymphocytic leukaemia. In these disorders, monoclonal Ig have never been studied at the molecular level. We conducted a pathological and molecular analysis in a patient with chronic lymphocytic leukaemia, glomerulonephritis and a single circulating monoclonal Ig. Unusual IgG1kappa kidney deposits were observed. The heavy and light chain variable region sequences of that cryoprecipitating monoclonal Ig were characterized. Light microscopy revealed glomerulonephritis typical of cryoglobulinaemia, with neutrophil and macrophage infiltration, endocapillary hyperplasia and few protein thrombi. Electron microscopic study clearly evidenced numerous subepithelial mixed granular and organized deposits with a unique microtubular organization, reminiscent of the GOMMID. The Ig molecule sequence revealed alterations of charge and hydrophobicity potentially promoting a crystal-like aggregation and the aggregation of microtubules. This description suggests that common mechanisms are involved in various forms of precipitation and/or deposition of complete Ig molecules, with a variable extent of organization and with a possible overlap between pathological patterns of either glomerulonephritis with microtubular deposits or type I cryoglobulinic glomerulonephritis.

Impact of treatment on extra hepatic manifestations in patients with chronic hepatitis C

BACKGROUND/AIMS

Fatigue and other extra hepatic manifestations of hepatitis C have never been studied prospectively in a large cohort. The aim was to assess the prevalence of these symptoms prior to any treatment, and on prolonged follow-up in treated and untreated patients.

METHODS

A single-center cohort of consecutive patients with chronic hepatitis C was investigated prior to any treatment. A questionnaire was completed every 6 months for 18 months of follow-up.

RESULTS

Of 1614 patients, 431 met the inclusion criteria (56% male; age 49 years; 60% with significant fibrosis or cirrhosis; 46% with cryoglobulinemia). Seventy-six were untreated; of the treated patients, 83 were sustained responders, 47 relapsers and 225 non-responders. At baseline, fatigue and other extrahepatic manifestations were present in 254 (59%) and 225 (52%) patients. Fatigue was improved in 29 of 83 (35%) responders versus 75 of 348 (22%) patients with detectable hepatitis C virus (HCV)-RNA (P=0.01). The impact of virologic response on fatigue persisted after adjusting for age, gender, fibrosis stage, and depression (odds ratio: 0.34, P<0.001). A cryoglobulin was detectable in two of 34 (6%) responders versus 38 of 115 (33%) patients with detectable HCV-RNA (P<0.001).

CONCLUSIONS

In hepatitis C, a sustained virologic response is associated with a reduction in fatigue and cryoglobulin, but fatigue frequently persists despite a virologic response.

[Hepatitis C and immunoglobulin heavy-chain gene rearrangement]

Hepatitis C virus (HCV) has cytopathogenic effect not only on hepatocytes, however on salivary glands, monocytes of peripheral blood and lymphoid cells, may explain the systemic manifestations of the infection. HCV activates B and T-cells, modifies the immune response, causes lymphoproliferation, leading the development of B-cell non-Hodgkin's lymphoma (NHL). In the majority of B-cell NHLs immunoglobulin heavy chain (IgH) and light chain (IgL) genes are rearranged and expressed on cell surface in the early stage of the ontogenesis. The analyses of IgH rearrangement prove the clonality of lymphoproliferative disorders giving a powerful approach to the B-cell origin identification of cell proliferation.

PATIENTS AND METHODS

IgH gene rearrangements were examined from the sera of 57 chronic HCV infected patients and 11 HCV-positive cryoglobulinemic patients as well.

RESULTS

Cryoglobulinemia was detected in 20% of all chronic hepatitis C virus infected patients and IgH rearrangement was observed in 10.29% (7/68), 4/7 patients (57.14%) suffered from cryoglobulinemia.

CONCLUSIONS

These results support the hypothesis that IgH gene rearrangement in HCV positive patients can indicate the lymphoproliferative disorder in the HCV infection released B-cell proliferation and lymphoma development.

Regression of lymphoproliferative disorder after treatment for hepatitis C virus infection in a patient with partial trisomy 3, Bcl-2 overexpression, and type II cryoglobulinemia

A patient with type II cryoglobulinemic vasculitis and hepatitis C virus (HCV) infection presented with a leukemiclike proliferation of B cells bearing marginal zone B-cell phenotypic markers. A partial trisomy 3 (bands 3q11-29) and overexpression of Bcl-2 without t(14;18) translocation was detected in the monoclonal B cells that were classic rheumatoid factor-producing B cells bearing the WA cross-idiotype. Treatment with interferon-alpha produced a complete clinical remission and synchronous marked decreases in viremia and monoclonal B-cell prevalence. This is the first report of partial trisomy 3 and Bcl-2 overexpression in type II cryoglobulinemic vasculitis associated with HCV infection. Further studies of HCV-infected patients with and without type II cryoglobulinemia are required to determine the prevalence and possible physiologic and/or pathophysiologic significance of these findings.

Hepatitis C virus related cryoglobulinemic glomerulonephritis

A 46 years male presented with skin rash and acute nephritic syndrome. He had history of jaundice four months back. Rheumatoid factor and cryoglobulins were present in the serum. Although anti-HCV antibodies were negative, HCV RNA was detected by polymerase chain reaction. Kidney biopsy showed membranoproliferative glomerulonephritis and thrombi in the lumen of the glomerular capillary loops. His renal functions improved with steroids.

Apheresis in cryoglobulinemia complicating hepatitis C and in other renal diseases

Removal of cryoglobulins by plasma exchange is now an accepted therapy. Cryoglobulins are circulating complexes that can deposit on small vessels and cause limited or extensive tissue injury. There are 3 major classes of cryoglobulins. Type I cryoglobulins are monoclonal and are detected in a variety of lymphoproliferative disorders. Type II cryoglobulins are mixed containing monoclonal and polyclonal IgG or IgM molecules. Type III cryoglobulins are also mixed and contain polyclonal IgG. Type II cryoglobulins are largely caused by hepatitis C virus infection; hence, they are the most common of the 3 types. In hepatitis C, cryoglobulins are linked to glomerular immune complex injury, often times accompanied by vasculitis of the skin, nerves, and other vital organs. Immediate removal of cryoglobulins by plasma exchange is an effective short-term treatment that can complement more-specific therapies. Plasma exchange has also been used to remove other circulating nephrotoxic agents such as antiglomerular basement antibodies that cause Goodpasture's syndrome, protease inhibitor autoantibodies that cause thrombotic thrombocytopenic purpura, and antiglomerular factors that cause some types of focal glomerulosclerosis.

[Prevention and treatment of viral hepatitis in renal insufficiency conditions]

Viral hepatotropic infections may lead to diagnostic and therapeutic problems in hemodialysis patients and kidney recipients. The parenteral and community-acquired routes of contamination of hepatitis B and C viruses explain their high frequency in this population. Their impact, because the immunosuppressive treatments, is harmful with a decrease in patients and allografts survival; cirrhosis is a contra-indication for renal transplantation since associated with a bad short-term prognosis and may require a combined kidney-liver transplantation. Thus, a liver biopsy is recommended in order to evaluate the histopathological severity of the liver disease (stage and grade) and to precise if an antiviral treatment appears necessary, especially because interferon-alpha, the main treatment of hepatitis B and C infections, is contra-indicated in kidney recipients because of the risk of graft rejection. In summary, the diagnosis of viral hepatotropic infections has to be early undergone and its pathological impact has to be evaluated by a liver biopsy. The best treatment has to be prophylactic (vaccination against hepatitis B virus and the respect of universal hygiene rules for hepatitis C virus).

Increased soluble p55 and p75 tumour necrosis factor-alpha receptors in patients with hepatitis C-associated mixed cryoglobulinaemia

To investigate whether tumour necrosis factor alpha (TNFalpha) plays a role in the pathogenesis of hepatitis C virus-associated mixed cryoglobulinaemia (HCV-MC), we measured soluble TNFalpha and its soluble p55 (sTNFR1) and p75 (sTNFR2) receptors in the serum of patients with HCV-MC. TNFalpha, sTNFR1 and sTNFR2 were measured in the serum of 32 patients with HCV-MC, 18 patients with hepatitis C without MC (HCV) and 18 healthy volunteers, using specific immunoassays. Correlations between clinical and biological parameters and the concentrations of TNFalpha and sTNFRs were established by studying detailed clinical records of the 32 HCV-MC patients. Although higher, TNFalpha levels were not significantly different in HCV-MC patients compared with healthy or HCV controls. sTNFR1 and sTNFR2, however, were significantly higher in HCV-MC compared with controls or with HCV patients, and higher concentrations of sTNFR1 and sTNFR2 were observed in patients with severe visceral vasculitis, compared with patients with limited purpura. sTNFR1 concentrations positively correlated with fibrinogen levels but TNFalpha, sTNFR1 and sTNFR2 did not correlate with other biological parameters such as rheumatoid factor concentrations, CH50 or C4 values. These data suggest a role for TNFalpha in the pathogenesis of the immune complex-mediated vasculitis associated with HCV-MC.

[Steroids, interferon-alpha and ribavirin treatment of cryoglobulinemic glomerulonephritis concurrent with HCV infection]

The treatment of mixed cryoglobulinemia concurrent with HCV infection is still under debate. We report the case of a patient referred to our unit for a membranoproliferative glomerulonephritis associated with HCV infection. A nephrotic syndrome and a slight reduction of glomerular filtration rate were present. We treated him with alpha-interferon for six months and prednisone for two months. We achieved a remission of the nephrotic syndrome without any significant reduction of the viral load. One year after the therapy had been suspended, the nephrotic syndrome relapsed and subsequently responded to a combined treatment with interferon ribavirin and prednisone. HCV-RNA became suddenly and persistently negative.

[Systemic manifestations of chronic hepatitis C]

It's well known that hepatitis C virus (HCV) related chronic liver disease may be associated with various extra hepatic disorders. These manifestations can revealed the hepatic disease. We review the available data on the conditions and asses their clinical implications: vascular, cutaneous, articular, neurological or renal disorders. There is no correlation between these extra hepatic manifestations and the severity of liver disease. Several recent studies have established a strong link between HCV infection and essential mixed cryoglobulinemia but some other extra hepatic associations are just fortuitous. Others datas are necessary to better analyze these extra hepatic disorders and to offer the beneficial treatment of patients with chronic hepatitis C.

Extrahepatic manifestations of infection with hepatitis C virus

Chronic hepatitis C is associated with, and may trigger or exacerbate, an extraordinary variety of extrahepatic manifestations. Most of these manifestations affect the skin, the most frequent and important of which are the leukocytoclastic vasculitis of MC type II and PCT. The former is an example of an autoimmune disorder triggered by HCV infection, whereas PCT is a skin disease caused by hepatic overproduction of uro- and 7-carboxyl porphyrins caused by increased oxidative stress in hepatocytes. Currently available effective therapies of CHC (IFN, ribavirin) may also trigger or exacerbate extrahepatic manifestations, especially including autoimmune thyroiditis, skin rashes, and hemolytic anemia.

Longterm efficacy of interferon-alpha for extrahepatic disease associated with hepatitis C virus infection

OBJECTIVE

To investigate longterm responsiveness to interferon-alpha (lFN-alpha) of patients with extrahepatic manifestations of hepatitis C virus (HCV) in a nonendemic area.

METHODS

We prospectively evaluated 11 patients with extrahepatic manifestations of HCV infection, including 10 with Type II cryoglobulins, treated with IFN-alpha--9 had cutaneous vasculitis, 6 arthralgias, 7 neuropathy, and 4 glomerulonephritis. Liver biopsies were performed on all patients, although 6/11 had normal liver function tests. All received 3 M units IFN-alpha tiw, with total length of treatment ranging from 3 mo to 5 yrs. Periodic assessments were made of clinical activity, biochemical variables, cryoglobulin quantitation, and HCV copy number.

RESULTS

Three patients were withdrawn because of toxicity. Three were nonresponders at 6, 16, and 17 mo of therapy, based on persistence of HCV RNA in blood, cryoprecipitates, and peripheral blood mononuclear cells. One patient was a partial responder at 3 yrs, with 2 major flares of cutaneous vasculitis occurring on separate attempts to withdraw IFN-alpha. Three patients (27.2%) were complete responders based on resolution of symptoms (purpura, neuropathy) and disappearance of cryoprecipitates and HCV RNA, but only one successfully tapered IFN-alpha after 3 yrs of treatment, with sustained resolution at followup 15 mo later.

CONCLUSION

IFN-alpha is safely tolerated for prolonged periods in patients with extrahepatic HCV infection, and is particularly effective for treatment of cutaneous vasculitis. Careful monitoring is needed for evolution of liver pathology to cirrhosis, or for progression of renal or neurologic disease.

A 385 insertion in the hypervariable region 1 of hepatitis C virus E2 envelope protein is found in some patients with mixed cryoglobulinemia type 2

Chronic hepatitis C virus (HCV) infection has been associated with development of mixed cryoglobulinemia type 2 (MC2), a lymphoproliferative disorder characterized by B cell monoclonal expansion and immunoglobulin M/k cryoprecipitable immunoglobulin production. A short sequence (codons 384-410) of the HCV E2 protein, which has the potential to promote B cell proliferation, was investigated in 21 patients with HCV-related MC2 and in a control group of 20 HCV carriers without MC2. In 6 of the 21 (29%) patients with MC2, all the clones isolated from plasma, peripheral blood mononuclear cells, and liver showed sequence length variation compared with the hypervariable region 1 (HVR1) consensus sequence; 5 patients had an insertion at codon 385, and 1 patient had a deletion at codon 384. Inserted residues at position 385 were different within and between patients. No such mutations were observed in any of the HVR1 clones from control patients without MC2, and the difference between the 2 groups was statistically significant (P =.02). Analysis of 1345 HVR1 sequences obtained from GenBank strongly supported the conclusion that the observed insertions and deletion represent a rare event in HCV-infected patients, suggesting that they are significantly associated with MC2. The physical and chemical profiles of the 385 inserted residues detected in the MC2 patients were consistent with the possibility that these mutations, which occurred in a region containing immunodominant epitopes for neutralizing antibodies and binding sites for B lymphocytes, may be selected by functional constraints for interaction with host cells.

[Characterization of cryoglobulin, M protein, low molecular weight IgM in a patient with chronic hepatitis C and type II mixed cryoglobulinemia]

The common extrahepatic manifestation of hepatitis C virus(HCV) infection is mixed cryoglobulinemia. We have analyzed serum cryoglobulin, IgM and various antibody activities from a patient with chronic hepatitis C and type II cryoglobulinemia. Cryoprecipitates were consisted of polyclonal IgG and monoclonal IgM-kappa with rheumatoid factor activity. About 20% of total IgM was found to be low molecular weight IgM by gel-filtration and SDS-PAGE. The anti-streptolysin O(ASO) activity measured by Latex agglutination method was found to be markedly elevated despite normal activity by Rantz-Randell method. The patient's serum has revealed to react against bovine gamma globulin, which crosslinked streptolysin O to Latex particles, in a nonspecific manner. Phenotypic analysis of the surface markers on abnormal lymphoid cells from peripheral blood and bone marrow showed monoclonal expansion of B-cell lineage by flow cytometry. The patient was treated with interferon-alpha, which resulted in an improvement of liver dysfunction, decreased amounts of cryoglobulin and IgM. It was concluded that the patient has suffered from lymphoproliferative disorder, namely HCV infection-associated primary macroglobulinemia.

Polyarteritis nodosa and mixed cryoglobulinaemia related to hepatitis B and C virus coinfection

OBJECTIVE

To determine the responsibility of hepatitis B virus (HBV) and hepatitis C virus (HCV) and therapeutic implications in a patient who developed systemic vasculitis.

CASE REPORT

The case of a 38 year old woman who had a past history of addiction to intravenous drugs and developed systemic vasculitis after infection by HBV and HCV is described. The clinical and laboratory findings substantiated not only the diagnosis of polyarteritis nodosa (PAN) but also that of mixed cryoglobulinaemia with a monoclonal IgMkappa component.

CONCLUSION

Because cryoglobulins are rarely found in HBV related PAN but often associated with HCV infection, and in light of the histological findings, cryoglobulinaemia was interpreted as being secondary to HCV infection. This example of a highly complex situation emphasises the need to gather all relevant clinical, biological, histological, and complementary data so that the best treatment for overlapping of distinct vasculitides can be selected.

Hepatitis C virus infection in patients with essential mixed cryoglobulinemia, multiple myeloma and chronic lymphocytic leukemia

Increased prevalence of HCV infection in some lymphoproliferative diseases has been recently reported. In the present study, the frequency of anti-HCV antibody (Ab) together with hepatitis B surface (HBs) antigen (Ag) and anti-HBs Ab were determined in 42, 45 and 23 patients with essential mixed cryoglobulinemia (EMC), multiple myeloma (MM) and B-cell chronic lymphocytic leukemia (B-CLL), respectively. Thirty hospitalized patients with chronic rheumatoid arthritis (RA) were also included as a control. Specific antibodies to HCV antigens were detected by enzyme linked immunosorbent assay (ELISA) and positive results were confirmed by a recombinant immunoblot assay (RIBA). Our results demonstrated anti-HCV positivity in 69%, 11% and 4.3% of the EMC, MM and B-CLL samples tested, respectively. None of the RA patients were found to be anti-HCV positive. No significant differences were observed between the patients groups regarding the frequency of HBs Ag and anti-HBs Ab. Considering the low incidence of HCV infection in the control group and the normal population, these results confirm and extend previous reports on the possible role of HCV infection in the etiology of EMC and further suggest involvement of this virus in a subset of MM.

Hepatitis C virus-associated mixed cryoglobulinemia. Clinical manifestations, histopathological changes, mechanisms of cryoprecipitation and options of treatment

Chronic hepatitis C virus (HCV) infection is frequently associated with a variety of autoimmune phenomenons. Mixed cryoglobulinemia (MC) appears in up to 50% of chronic HCV-infected patients. Cryoglobulins consist of immunoglobulin complexes precipitating in vitro when cooled below body temperature. In most cases IgM with rheumatoid factor activity is found in cryoprecipitates which could lead to vasculitis induced by the deposition of immnuocomplexes in small vessels. This vasculitis is thought to cause clinical symptoms called Meltzer's triad. This triad is represented by purpura, arthralgia and weakness. One third of patients suffering from HCV-associated mixed cryoglobulinemia are developing typical symptoms during their course of disease. The striking association between HCV infection and MC has conduced to the hypothesis that HCV is of major importance in the production of MC with followed vasculitis. Both hepatrophism and lymphotrophism have been reported for the hepatitis C virus. Infection of B-cells by HCV could probably lead to a bcl-2 translocation and immunoglobulin gene rearrangement which results in clonal lymphoproliferation and in synthesis of monoclonal IgM with rheumatoid factor activity. These IgM form immunocomplexes with IgG in the cold, which are finally responsible for the described vasculitis. Histopathological changes of the liver are dominated by chronic HCV infection. The majority of times mild activity of hepatitis or mild fibrosis could be found. Nevertheless, cirrhosis is more often found in HCV-infected patients suffering from MC compared to patients without MC. Conventional treatment of MC is aimed to reduce circulating immune complexes by immunosupression and plasmapheresis. With the emerging concept of a viral pathogenesis the therapeutic approach has changed during the last decade. Interferon treatment of MC, particularly of HCV-associated MC is well established nowadays.