Hepatitis C virus in patients with cryoglobulinemia type II

Management of hepatitis C virus-related mixed cryoglobulinemia

Mixed cryoglobulinemia is a chronic immune complex-mediated disease strongly associated with hepatitis C virus (HCV) infection. Mixed cryoglobulinemia is a vasculitis of small and medium-sized arteries and veins, due to the deposition of complexes of antigen, cryoglobulin and complement in the vessel walls. The main clinical features of mixed cryoglobulinemia vasculitis include the triad of palpable purpura, arthralgias, and weakness, and other pathological conditions such as glomerulonephritis, peripheral neuropathy, skin ulcers, and widespread vasculitis. The treatment of HCV-related mixed cryoglobulinemia is difficult due to the multifactorial origin and clinical polymorphism of the syndrome. It can be directed to eradicate the HCV infection, suppress the B-cell clonal expansion and cryoglobulin production, or ameliorate symptoms. The choice of the most appropriate treatment is strictly related to the assessment of disease activity, and to the extent and severity of organ involvement.

Cryoglobulin evaluation: best practice?

Cryoglobulins are serum immunoglobulins that precipitate at temperatures below 37 degrees C and re-dissolve on warming. Cryoglobulinaemia leads to variable symptoms including characteristic purpura, ischaemia of extremities, renal failure, peripheral neuropathy, abdominal pain secondary to intestinal ischaemia and arthralgias. Cryoglobulin testing is underutilized in clinical practice. It has been neglected in clinical laboratories and by clinicians due to several factors, such as the length of time it takes for serum cryoglobulin analysis to be performed in the laboratory, the perceived difficulty in getting optimal sampling conditions and a failure to appreciate that even apparently low levels of cryoglobulin can be associated with severe symptoms in some patients. The most important variable confounding standardization of cryoglobulin testing is improper sample handling. A recent report critically appraising the current practice of cryoglobulin evaluation in 137 laboratories in Europe by United Kingdom National External Quality Assurance Scheme (UKNEQAS) illustrated the wide variability in practice. Although many clinical laboratories perform cryoglobulin evaluation, there are widespread differences in the methodology used and the care with which this is carried out and this leads to considerable intralaboratory and interlaboratory variability. The most common sources of error are false-negative results due to loss of cryoprecipitate during transport and storage. Better standardization is needed to avoid missed diagnoses and improve the comparability of results. Laboratories should ensure that sample temperature is maintained at 37 degrees C until the serum is separated. In this article, we briefly review the classification and clinical features of cryoglobulins and suggest best practice guidelines for laboratory detection and identification of cryoglobulins.

Rituximab as a therapeutic tool in severe mixed cryoglobulinemia

Type II mixed cryoglobulinemia (MC) is a systemic vasculitis, associated in most cases with hepatitis C virus (HCV) infection, sustained by proliferation of oligoclonal cells. Systemic B cell depletion and clinical remission can be achieved in non-Hodgkin lymphoma by human/mouse chimeric monoclonal antibody that specifically reacts with the CD20 antigen (rituximab). Similar effects could be expected in type II MC. Twelve patients, mean age 61.9 years (range 37-76), 11 with HCV infection genotype 2a2c (4 cases) or 1b (6 cases) and 3 (1 case) and symptomatic type II MC with systemic manifestations, including renal involvement, marrow clonal restriction, large necrotizing ulcers, and polyneuropathy, were considered eligible for rituximab therapy because of resistance or intolerance to conventional therapy or important bone marrow infiltration. Rituximab was administered intravenously at a dose of 375 mg/m2 on days 1, 8, 15, and 22. Two more doses were administered 1 and 2 months later. No other immunosuppressive drugs were added. Response was evaluated by assessing the changes in clinical signs, symptoms, and laboratory parameters. Levels of proteinuria, hematuria, erythrocyte sedimentation rate, cryocrit, rheumatoid factor, and IgM decreased while C4 values increased and HCV viral load remained stable during short- and medium-term observation. Bone marrow abnormalities were found to reverse to normal. Constitutional symptoms disappeared or ameliorated. No acute or delayed side effects were seen. Based on this experience and a number of reports published in the last 5 years, Rituximab appears to be a safe and effective therapeutic option in symptomatic patients with HCV-associated MC with signs of systemic vasculitis.

Hepatitis C virus infection induced vasculitis

Cryoglobulinemia are immune complexes that may induce systemic cryoglobulinemic vasculitis, a small-vessel vasculitis involving the skin, the joints, the peripheral nerve system, and the kidneys. During the last 15 years, progresses have been done after the discovery of the hepatitis C virus, the main cause of cryoglobulins. Main factors associated with cryoglobulin production are female gender, alcohol intake above 50 g/day, extensive liver fibrosis, and steatosis. Symptomatic cryoglobulins (i.e., vasculitis) are associated with older age, longer duration of infection, and main characteristics of cryoglobulin (type II, IgM kappa, high serum levels). The physiopathology is complex, and it involves humoral immunity, B- and T-cellular immunity but not the virus itself. Peg-Interféron alpha Ribavirine combination leads to a virological and clinical response of the vasculitis in about 70% of patients. In nonresponders, recent open series suggested the efficacy of Rituximab with a good response in up to 80% of patients but a relapse in 42% after 7 months after the last infusion. For future prospects and projects, new therapeutic strategies include a combination of best antiviral treatment with Peg-Interferon plus Ribavirin and Rituximab. Multicenter controlled trials are mandatory.

Mixed cryoglobulinemia

Mixed cryoglobulinemia (MC), type II and type III, refers to the presence of circulating cryoprecipitable immune complexes in the serum and manifests clinically by a classical triad of purpura, weakness and arthralgias. It is considered to be a rare disorder, but its true prevalence remains unknown. The disease is more common in Southern Europe than in Northern Europe or Northern America. The prevalence of 'essential' MC is reported as approximately 1:100,000 (with a female-to-male ratio 3:1), but this term is now used to refer to a minority of MC patients only. MC is characterized by variable organ involvement including skin lesions (orthostatic purpura, ulcers), chronic hepatitis, membranoproliferative glomerulonephritis, peripheral neuropathy, diffuse vasculitis, and, less frequently, interstitial lung involvement and endocrine disorders. Some patients may develop lymphatic and hepatic malignancies, usually as a late complication. MC may be associated with numerous infectious or immunological diseases. When isolated, MC may represent a distinct disease, the so-called 'essential' MC. The etiopathogenesis of MC is not completely understood. Hepatitis C virus (HCV) infection is suggested to play a causative role, with the contribution of genetic and/or environmental factors. Moreover, MC may be associated with other infectious agents or immunological disorders, such as human immunodeficiency virus (HIV) infection or primary Sjögren's syndrome. Diagnosis is based on clinical and laboratory findings. Circulating mixed cryoglobulins, low C4 levels and orthostatic skin purpura are the hallmarks of the disease. Leukocytoclastic vasculitis involving medium- and, more often, small-sized blood vessels is the typical pathological finding, easily detectable by means of skin biopsy of recent vasculitic lesions. Differential diagnoses include a wide range of systemic, infectious and neoplastic disorders, mainly autoimmune hepatitis, Sjögren's syndrome, polyarthritis, and B-cell lymphomas. The first-line treatment of MC should focus on eradication of HCV by combined interferon-ribavirin treatment. Pathogenetic treatments (immunosuppressors, corticosteroids, and/or plasmapheresis) should be tailored to each patient according to the progression and severity of the clinical manifestations. Long-term monitoring is recommended in all MC patients to assure timely diagnosis and treatment of the life-threatening complications. The overall prognosis is poorer in patients with renal disease, liver failure, lymphoproliferative disease and malignancies.

Chronic hepatitis C virus infection: Prevalence of extrahepatic manifestations and association with cryoglobulinemia in Bulgarian patients

AIM: To assess the prevalence of extrahepatic manifestations in Bulgarian patients with chronic hepatitis C virus (HCV) infection and identify the clinical and biological manifestations associated with cryoglobulinemia.

METHODS: The medical records of 136 chronically infected HCV patients were reviewed to assess the prevalence of extrahepatic manifestations. Association between cryoglobulin-positivity and other manifestations were identified using χ² and Fisher’s exact test. Risk factors for the presence of extrahepatic manifestations were assessed by logistic regression analysis.

RESULTS: Seventy six percent (104/136) of the patients had at least one extrahepatic manifestation. Clinical manifestations included fatigue (59.6%), kidney impairment (25.0%), type 2 diabetes (22.8%), paresthesia (19.9%), arthralgia (18.4%), palpable purpura (17.6%), lymphadenopathy (16.2%), pulmonary fibrosis (15.4%), thyroid dysfunction (14.7%), Raynaud’s phenomenon (11.8%), B-cell lymphoma (8.8%), sicca syndrome (6.6%), and lichen planus (5.9%). The biological manifestations included cryoglobulin production (37.5%), thrombocytopenia (31.6%), and autoantibodies: anti-nuclear (18.4%), anti-smooth muscle (16.9%), anti-neutrophil cytoplasm (13.2%) and anti-cardiolipin (8.8%). All extrahepatic manifestations showed an association with cryoglobulin-positivity, with the exception of thyroid dysfunction, sicca syndrome, and lichen planus. Risks factors for the presence of extrahepatic manifestations (univariate analysis) were: age ≥ 60 years, female gender, virus transmission by blood transfusions, longstanding infection (≥ 20 years), and extensive liver fibrosis. The most significant risks factors (multivariate analysis) were longstanding infection and extensive liver fibrosis.

CONCLUSION: We observed a high prevalence of extrahepatic manifestations in patients with chronic HCV infection. Most of these manifestations were associated with impaired lymphoproliferation and cryoglobulin production. Longstanding infection and extensive liver fibrosis were significant risk factors for the presence of extrahepatic manifestations in HCV patients.

Mixed cryoglobulinemia: a model of virus-related disease in internal medicine

Like other hepatotropic viruses, hepatitis C virus (HCV) exhibits the property of inducing hepatocellular damage, possibly through induction of immune mechanisms that lead to hepatocellular necrosis. The early activated mechanisms include production of non-specific and specific antibodies, which represent the first line of defence against invading foreign pathogens. As a consequence, circulating immune complexes are promptly formed and antigen uptake and processing by specialized cells are enhanced. A major fraction of circulating immunoglobulins (Igs) are part of the spectrum of so-called "natural" antibodies, which include anti-idiotypic antibodies and molecules with rheumatoid factor (RF) activity. They mainly belong to the IgM class, are polyclonal and have no intrinsic pathogenetic potential. In 20-30% of HCV-infected patients, RFs share characteristics of high affinity molecules, are monoclonal in nature, and result in the production of cold-precipitating immune complexes and mixed cryoglobulinemia (MC). The persistent production of monoclonal RF molecules implies the existence of a further mechanism capable of restricting the reactivity and reflects a distinct selection of a cell population that can be maintained throughout life because it is continuously exposed to antigen pressure. Either polyclonal or monoclonal profiles of B-cell expansion are demonstrable in the liver of the majority of HCV-infected patients. The frequent detection of oligoclonal B cell expansion may, indeed, represent a key pathobiologic feature which sustains non-malignant B-cell lymphoproliferation. The preferential expansion of one clone would in turn lead to a monoclonal pattern, which could favor stochastic oncogenic events. Thus, it can be postulated that HCV is the stimulus not only for the apparent benign lymphoproliferative process underlying a wide spectrum of clinical features, but also for the progression to frank lymphoid malignancy in a subgroup of patients.

Thymic stromal lymphopoietin transgenic mice develop cryoglobulinemia and hepatitis with similarities to human hepatitis C liver disease

Essential mixed cryoglobulinemia in humans is strongly associated with chronic hepatitis C virus infection. It remains controversial whether liver injury in hepatitis C is primarily attributable to direct viral cytopathic effect or to an immune-mediated response. We characterized the role of cryoglobulinemia in the development of liver disease in thymic stromal lymphopoietin (TSLP) transgenic mice that produce mixed cryoglobulinemia and develop hepatitis. The role of immune complexes in this animal model was evaluated using techniques of light, immunofluorescence, and electron microscopy. To assess the role of Fc receptor engagement in mediation of the disease, TSLP transgenic mice were crossbred with mice deficient for immunoglobulin-binding receptor gamma IIb (FcgammaRIIb). Livers from the TSLP transgenic animals showed mild to moderate liver injury, minimal to mild fibrosis, and deposition of immunoglobulin around the portal tracts. TSLP transgenic mice deficient in inhibitory FcgammaRIIb had more severe hepatitis and accelerated mortality. TSLP-associated hepatitis bears strong similarity to hepatitis C virus-related hepatitis as it occurs in humans, making this a valuable model system of chronic hepatitis and fibrosis to study therapies aimed at manipulating immune responses. Periportal immune complex deposition may play an important role in the pathogenesis of hepatitis occurring in the setting of systemic cryoglobulinemia.

Agonistic antibodies to Fas induce a breach in the endothelial lining of the liver and a breakdown in B cell tolerance

Liver disease can be associated with a breakdown in self-tolerance and the production of autoantibodies such as rheumatoid factors (RF), which bind to IgG. Here we investigated whether primary, non-infectious liver damage was sufficient to induce autoantibody production. We established a model of targeted liver damage induced by weekly sublethal injections of pro-apoptotic anti-Fas (CD95) antibodies. Liver damage, monitored by measurements of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, was minimal 1 week after anti-Fas injection. However, the sublethal Fas stimulation was sufficient to trigger significant haemorrhage in the liver, as assessed by Evans Blue dye leakage into the organ 5 h after anti-Fas antibody injection. We observed an induction of RF in response to the weekly injections of sublethal anti-Fas antibodies but not of isotype control antibodies, indicating a breakdown of self-tolerance induced by Fas engagement. RF induction was unlikely to be due to direct activation of B cells, as splenocytes stimulated with anti-Fas antibodies in vitro did not produce RF. These studies show that sublethal damage to the liver by Fas engagement leads to liver haemorrhage and is sufficient to trigger the breakdown of self-tolerance.

Rheumatoid factor induction in murine models of liver injury

Alcoholic liver disease and hepatitis C are associated with the production of autoantibodies such as rheumatoid factors (RF), which bind to IgG and can aid in host defence, but are also associated with pathological conditions such as rheumatoid arthritis. Because little is known about the role of RF in liver disease, we characterized the RF production that either occurred spontaneously in response to alcohol consumption or was induced by injection of an Escherichia coli glycolipoprotein in C57Bl/6 mice. Whereas severe liver damage was induced by carbon tetrachloride (CCl(4)), minimal damage was caused by chronic alcohol consumption. Liver damage was monitored by measurements of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Circulating RF was induced in response to chronic alcohol consumption; the latter probably involved Toll-like receptor ligation. In contrast, CCl(4)-induced damage was not associated with RF induction. However, concurrent treatment with an E. coli glycolipoprotein macromolecule that induced RF, protected against CCL(4)-induced liver damage as measured by a highly significant decrease (P = 0.008) at 4 weeks in AST and ALT. RF induced by E. coli glycolipoprotein correlated with 'protection' from liver damage, indicating that the RF autoimmune response does not necessarily exacerbate liver disease.

Cryoglobulinemia related to hepatitis C virus infection

A causal link among hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia, cryoglobulinemic glomerulonephritis, and vasculitis is strongly supported. HCV triggers autoimmune response in predisposed individuals that manifests as organ-specific and non-organ-specific autoantibodies and as polyclonal/monoclonal rheumatoid factor, which has a central role in causing damaging cryoglobulin and immune complex tissue levels. Immunologic events are mainly induced by HCV infection persistence, with excessive immune stimulation. Humoral immune dysfunction leads to autoantibodies and rheumatoid factor production with cryoglobulinemia, glomerulonephritis, vasculitis, neuropathy, and probably thyroiditis, and arthritis in rare cases. Cellular immune dysfunction leads to lymphocytic infiltration, proliferation, and cytokine production. Pegylated (or not) interferon-alpha in combination with ribavirin appears to be the treatment of choice for patients with symptomatic essential mixed cryoglobulinemia with or without glomerulonephritis. Novel treatment with rituximab is promising.

Multicenter study on hepatitis C virus-related cryoglobulinemic glomerulonephritis

BACKGROUND

Mixed cryoglobulinemia is a multisystem disorder associated strongly with hepatitis C virus (HCV) infection. The kidney frequently is involved, and glomerulonephritis represents the key factor affecting prognosis.

METHODS

Clinical, serological, immunogenetic, and morphological data were collected retrospectively from medical records of 146 patients with cryoglobulinemic glomerulonephritis who underwent biopsies in 25 Italian centers and 34 cryoglobulinemic controls without renal involvement.

RESULTS

Eighty-seven percent of patients were infected with HCV; genotype 1b was more frequent than genotype 2 (55% versus 43%). Diffuse membranoproliferative glomerulonephritis was the most prevalent histological pattern (83%). Type II cryoglobulin (immunoglobulin Mkappa [IgMkappa]/IgG) was detected in 74.4% of cases. The remainder had type III (polyclonal IgM/IgG) cryoglobulins. A multivariate Cox proportional hazard model showed that age, serum creatinine level, and proteinuria at the onset of renal disease were associated independently with risk for developing severe renal failure at follow-up. Overall survival at 10 years was about 80%. Kaplan-Meier survival curves were worsened by a basal creatinine value greater than 1.5 mg/dL (>133 mumol/L), but were unaffected by sex and HCV infection. Cardiovascular disease was the cause of death in more than 60% of patients.

CONCLUSION

Data confirm the close association between mixed cryoglobulinemia and HCV infection and between glomerulonephritis and type II cryoglobulin. Survival profiles are better than previously reported in the literature, probably because of improvement in therapeutic regimens. Causes of death reflect this improvement in survival, with an increased prevalence of cardiovascular events compared with infectious complications and hepatic failure, which were predominant in the past.

Dangerous small B-cell clones

The detection of a monoclonal immunoglobulin in serum or urine usually raises concerns about the size of the underlying B-cell-derived clone and possible systemic effects caused by its expansion. However, a small clone can synthesize a very toxic protein, producing devastating systemic damage and protean clinical presentations. The resulting "monoclonal component-related diseases," although difficult to diagnose, may be progressive and even fatal. The monoclonal protein can aggregate and deposit systemically as occurs in light-chain amyloidosis, monoclonal immunoglobulin deposition disease, crystal-storing histiocytosis, and monoclonal cryoglobulinemia. Alternatively, some monoclonal proteins possess antibody activity toward autogenous antigens and cause chronic cold agglutinin disease, mixed cryoglobulinemia, and peripheral neuropathies. Other humoral mediators may contribute to neuropathy in variant disorders such as the POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes) syndrome. The clone synthesizing the noxious monoclonal proteins is often small, and sensitive techniques may be required to detect these immunoglobulins. A delay in diagnosis can allow irreversible organ damage and dramatically shorten survival. Prompt recognition of suggestive signs and symptoms should trigger a thorough diagnostic approach to reach the correct diagnosis quickly, because this is the key to effective therapy. Although the treatment of these conditions is not optimal, significant advances have been made, improving the duration and quality of life.

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.

Positive Serum Cryoglobulin Is Associated with Worse Outcome after Liver Transplantation for Chronic Hepatitis C

BACKGROUND

Recurrent hepatitis C virus (HCV) infection in patients after liver transplantation is an important clinical problem. Because serum cryoglobulins (CG) are known to be associated with an increased incidence of cirrhosis in nontransplant patients, the authors tested the hypothesis that CG would also predict aggressive recurrent HCV in patients after liver transplantation.

METHODS

Using a longitudinal database, the outcomes of 105 allografts transplanted into 97 HCV-positive patients from 1991 through 2002 were analyzed on the basis of CG status using a retrospective cohort design. Fifty-nine CG-negative and 38 CG-positive patients were identified. Histologic outcomes and graft survival were analyzed using Kaplan-Meier estimates and Cox univariate and multivariate analyses. Both overall survival and HCV-specific survival (non-HVC-related deaths and graft losses censored) were analyzed.

RESULTS

By Kaplan-Meier estimates, CG-positive patients showed earlier graft failure with decreased time to severe histologic activity and fibrosis as compared with CG-negative patients (P<0.05 for all outcomes). By univariate analysis, CG-positive patients had significantly higher risk ratios for shortened HCV-specific graft survival, severe activity-free survival, and severe fibrosis-free survival as compared with CG-negative patients (P<0.05 for all outcomes). In the multivariate model, CG was an independent predictor for severe activity-free, severe fibrosis-free, and HCV-specific graft survival (P<0.05 for all outcomes).

CONCLUSIONS

CG-positivity is associated with severe recurrent HCV disease in liver transplant recipients.

Hepatitis C virus, cryoglobulinaemia, and vasculitis: immune complex relations

Several viruses are involved in the development of systemic vasculitides. Hepatitis C virus (HCV) has been shown to be closely related to mixed cryoglobulinaemia, an immune complex-mediated vasculitis. HCV particles and non-enveloped nucleocapsid protein participate in the formation of immune complexes. Once formed, immune complexes precipitate in many organs, including the skin, kidneys, and peripheral nerve fibres. Viral proteins confer peculiar physical and chemical properties on cryoimmunoglobulins. Since expansion of rheumatoid factor-synthesising B cells is the biological hallmark of mixed cryoglobulinaemia, it may be that the combination of rheumatoid factor activity and cryoprecipitability is responsible for the vasculitis. B-cell clonal expansion occurs primarily in the liver and correlates with a high intrahepatic viral load, pointing to a major role for HCV in the emergence and maintenance of B-cell clonalities. Recognition of HCV as an aetiological factor in most cryoglobulinaemic vasculitides has dramatically changed the approach to their treatment. Emphasis, in fact, is now placed on abatement of the viral load and deletion of B-cell clonalities.

Review article: hepatitis C virus infection and type-2 diabetes mellitus in renal diseases and transplantation

A link between hepatitis C virus infection and development of diabetes mellitus has been suggested by many investigators; however, this remains controversial. The mechanisms underlying the association between hepatitis C virus and diabetes mellitus are unclear but a great majority of clinical surveys have found a significant and independent relationship between hepatitis C virus and diabetes mellitus after renal transplantation and orthotopic liver transplantation. We have systematically reviewed the scientific literature to explore the association between hepatitis C virus and diabetes mellitus in end-stage renal disease; in addition, data on patients undergoing orthotopic liver transplantation were also analysed. The unadjusted odds ratio for developing post-transplant diabetes mellitus in hepatitis C virus-infected renal transplant recipients ranged between 1.58 and 16.5 across the published studies. The rate of anti-hepatitis C virus antibody in serum was higher among dialysis patients having diabetes mellitus (odds ratio 9.9; 95% confidence interval 2.663-32.924). Patients with type-2 diabetes-related glomerulonephritis had the highest anti-hepatitis C virus prevalence [19.5% (24/123) vs. 3.2% (73/2247); P < 0.001] in a large cohort of Japanese patients who underwent renal biopsy. The link between hepatitis C virus and diabetes mellitus may explain, in part, the detrimental role of hepatitis C virus on patient and graft survival after orthotopic liver transplantation and/or renal transplantation. Preliminary evidence suggests that anti-viral therapies prior to renal transplantation and novel immunosuppressive regimens may lower the occurrence of diabetes mellitus in hepatitis C virus-infected patients after renal transplantation. Clinical trials are under way to assess if the hepatitis C virus-linked predisposition to new onset diabetes mellitus after renal transplantation may be reduced by newer immunosuppressive medications.

[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.

Nail fold videocapillaroscopy in mixed cryoglobulinaemia

BACKGROUND

Nail fold videocapillaroscopy (NVC) has been extensively used to examine morphological and functional changes of microcirculation in connective tissue diseases. The nutritional circulation that depends on tissue capillaries, can be expected to be significantly impacted in mixed cryoglobulinaemia (MC).

METHODS

Using NVC, we evaluated 29 patients with MC (19 women), mean age 66 years (range 40-83). They included 28 hepatitis C virus (HCV) positive patients-14 genotype 1b, 10 genotype 2a 2c, two genotype 4, two with undetermined genotype. Of them, 18 had type II (IgMk-IgG) MC and 11 had type III. All patients were symptomatic, presenting with weakness (24 of 29 patients), arthralgia (24), purpura (16), peripheral neuropathy (20), Raynaud's phenomenon (8), hypertension (19) and membranoproliferative glomerulonephritis (MPGN) (9). The nail fold capillaries of four fingers per hand were examined using a videomicroscope.

RESULTS

Of the 29 patients, 27 had morphological abnormalities (including tortuosity and apical enlargement), 18 had capillaries with deeply altered orientations, 17 had shortened capillaries and 20 neoangiogenetic phenomena. These four types of capillary abnormalities were simultaneously present in 10, suggesting this combination to be a characteristic pattern in MC. Less common alterations included haemorrhages (10 cases), enlarged and giant capillaries (2) and avascular areas (2). The patients with MC-associated MPGN had a significantly greater number of capillary abnormalities (mean 4.5, range 4-6) than non-nephritic patients (mean 3.5, range 1-6, P = 0.01). The number of capillary abnormalities was not related to the presence of Raynaud's phenomenon. Microcirculatory changes did not correlate with other clinical manifestations or serological indices, including cryocrit, cryoglobulin type, HCV genotype, viral load, haemoglobin, ALT, rheumatoid factor, IgM and C4 levels.

CONCLUSIONS

Patients with MC show a variety of microcirculatory changes, often clustered in a characteristic pattern of abnormally oriented, short capillaries and neoangiogenetic phenomena. Capillary changes are more numerous in nephritic patients.

Ig V region restrictions in human chronic lymphocytic leukemia suggest some cases have a common origin

The factors that contribute to the development of B cell chronic lymphocytic leukemia (B-CLL) are unknown, and the groups of individuals at the greatest risk for developing this common leukemia are not well defined. Molecular features are important for classifying cases of B-CLL, and it is now apparent that similarities among Ig rearrangements between patients may give important clues to the origin of this disease.

Heat insoluble cryoglobulin associated with gangrene in multiple myeloma

Cryoglobulins are immunoglobulins that have tendency to precipitate in temperatures below 37 degrees C and dissolve with rewarming. Monoclonal cryoglobulins are usually associated with a distinct hematological disorder and often are asymptomatic. Heat insoluble cryoglobulin has been described with Sjogren's syndrome and glomerulonephritis but, not with multiple myeloma. Severe sensitivity to cold occurs with high thermal insolubility of the cryoprotein, with dramatic symptoms when exposed to minimal lowering of the temperature. We report a case of a 49 year old man with multiple myeloma and an unusual type I cryoglobulin that caused occlusive gangrene. The cryoglobulin appeared as a milky white precipitate that was resistant to re-suspension and did not dissolve at 37 degrees C. Immunoelectrophoresis of the cryoglobulin, which dissolved at 56 degrees C, showed it to be composed of a monoclonal IgG kappa protein (3.5 g/dl). Unlike most high thermal insoluble cryoglobulin, cold associated symptoms were not seen. In addition to steroids, plasmapheresis was initiated thrice a week with albumin fluid replacement. Plasmapheresis caused a marked decline in cryocrit levels from 21% to less than 0.5% in 9 days after 4 procedures with resolution of the gangrene of the feet and after 6 treatments, vasculitic symptoms improved dramatically. The cryoglobulin test was negative 2 weeks after initiation of treatment. The patient was treated for the myeloma and there was no recurrence of occlusive symptoms. Proper laboratory procedure and careful examination and handling of cryoglobulinemic samples facilitate detection of unusual cryoglobulins. This is a unique report of multiple myeloma with gangrene of lower extremities that has a heat insoluble cryoglobulin.

Occult hepatitis C virus infection in type II mixed cryoglobulinaemia

Mixed cryoglobulinaemia, when not secondary to other well-defined immunological disorders, is commonly associated with hepatitis C virus (HCV) infection. However, a minority of cases lack evidence of HCV infection and are, therefore, defined as 'true essential' mixed cryoglobulinaemias. We thoroughly investigated three such patients to determine the aetiology of this disorder. Antibodies to HCV (anti-HCV) and HCV RNA, detected by sensitive enzyme-linked immunosorbent and polymerase chain reaction assays in serum and in concentrated cryoglobulins, were repeatedly negative in the three patients. Despite the lack of evidence for HCV infection, two of them were still treated with interferon alpha-2a assuming unrecognized viral infection. Both patients demonstrated excellent clinical and laboratory responses, but cryoglobulinaemia relapsed after the withdrawal of therapy. At the time of relapse, HCV RNA genomic sequences were detected for the first time in the cryoprecipitates of both patients. In the third case, HCV RNA was demonstrated for the first time during a flare of cryoglobulinaemia coincident with varicella infection. In all three patients anti-HCV antibodies remained negative throughout follow-up. We conclude that some apparently 'essential' forms of mixed cryoglobulinaemia can be caused by occult HCV infection. Interferon therapy can be taken into consideration in such HCV-negative cases.

Prevalence and incidence of cryoglobulins in hepatitis C virus-related chronic hepatitis patients: a prospective study

OBJECTIVE

A high prevalence of cryoglobulins has been reported in patients with hepatitis C virus (HCV)-related liver disease. The aim of this study was to evaluate the prevalence and the incidence of cryoglobulins and their association with clinical symptoms in chronic hepatitis and cirrhosis patients.

METHODS

The prevalence of cryoglobulins and cryoglobulinemic syndrome was investigated at enrollment in 237 patients (213 with chronic hepatitis and 24 with cirrhosis). A 7-yr follow-up was conducted evaluating the occurrence of cryoglobulins and/or cryoglobulinemic syndrome every 6 months. Rheumatoid factor was also tested in all patients.

RESULTS

Prevalence of rheumatoid factor, cryoglobulins, and cryoglobulinemic syndrome in chronic hepatitis patients were 2%, 0.8%, and 0%, respectively. In cirrhosis patients the prevalence was 4%, 8%, and 0%, respectively. No statistically significant differences were found between the two groups. During the follow-up only one patient for each group abruptly developed cryoglobulinemic syndrome, and none of the patients who showed signs of cryoglobulinemia developed the syndrome or showed signs of evolution of the disease.

CONCLUSIONS

Our data demonstrate that the presence of cryoglobulins and/or cryoglobulinemic syndrome in HCV-related liver disease is unusual, as is the occurrence of cryoglobulinemia over time in these patients. This leads us to think that HCV-related cryoglobulinemic syndrome and HCV-related liver disease are independent diseases. This supports new and indirect evidence for an independent and direct role of HCV in liver and blood disorders.

Hepatitis C virus-associated tubulointerstitial injury

BACKGROUND

Tubulointerstitial damage is recognized as a determinant of the prognosis of kidney disease. Various types of viral infection have been reported to induce tubulointerstitial lesions; however, that caused by hepatitis C virus (HCV) remains unclear, although glomerular lesions caused by this viral infection have been well documented.

METHODS

To identify any association, we retrospectively investigated 320 patients who underwent renal biopsy and did not have extrarenal diseases causing tubulointerstitial nephritis.

RESULTS

Of these patients, 13 patients had HCV infection and 307 patients did not. In a case-control study, HCV infection showed a significant association with the prevalence of tubulointerstitial injury. To offset the secondary tubulointerstitial change caused by advanced glomerulopathy, we performed a glomerular stage-matched comparison of patients with membranous nephropathy (MN). Nine patients with MN among the 13 HCV-infected patients and 18 HCV-negative patients with electron microscopic glomerular stage-matched MN were randomly selected from the overall pool of patients. Comparing areas of interstitial fibrosis and inflammatory cell infiltration, both were greater in HCV-infected than HCV-negative patients. In biopsy tissues from HCV-infected patients, positive signal for HCV was observed in the perinuclear area of tubular epithelial cells and infiltrating cells on immunohistochemistry and in situ hybridization. By a strand-specific reverse-transcription polymerase chain reaction for HCV, both genomic- and replicative-strand RNA were detected in renal tissues.

CONCLUSION

These results suggest that HCV infection is a potent pathogenic factor of tubulointerstitial injury.

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.

Role of plasma membrane lipid microdomains in respiratory syncytial virus filament formation

The fusion protein (F) of respiratory syncytial virus (RSV) is the envelope glycoprotein responsible for the characteristic cytopathology of syncytium formation. RSV has been shown to bud from selective areas of the plasma membrane as pleomorphic virions, including both filamentous and round particles. With immunofluorescent microscopy, we demonstrated evidence of RSV filaments incorporating the fusion protein F and colocalizing with a lipid microdomain-specific fluorescent dye, 1,1-dihexadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate. Western blot analysis of Triton X-100 cold-extracted membrane fractions confirmed the presence of RSV proteins within the lipid microdomains. RSV proteins also colocalized with cellular proteins associated with lipid microdomains, caveolin-1, and CD44, as well as with RhoA, a small GTPase. ADP-ribosylation of RhoA by Clostridium botulinum exotoxin inactivated RhoA signaling and resulted in the absence of RSV-induced syncytia despite no significant change in viral titer. We demonstrated an overall decrease in both the number and length of the viral filaments and a shift in the localization of F to nonlipid microdomain regions of the membrane in the presence of C3 toxin. This suggests that the selective incorporation of RSV proteins into lipid microdomains during virus assembly may lead to critical interactions of F with cellular proteins, resulting in microvillus projections necessary for the formation of filamentous virus particles and syncytium formation. Thus, manipulation of membrane lipid microdomains may lead to alterations in the production of viral filaments and RSV pathogenesis and provide a new pharmacologic target for RSV therapy.

Glomerular disease in the tropics

Glomerular disease in the tropics differs considerably from that in temperate climates and between the developed and the developing world. The prevalence and pattern of glomerular disease in the tropics in turn varies widely in different geographic regions and is influenced by environmental, nutritional, and socioeconomic factors. Among the infective agents that have been identified as contributing to an increased prevalence of glomerular disease in the tropics are Plasmodium malaria, Schistsomiasis mansoni, Mycobacterium leprosy, and hepatitis B virus (HBV). A decline in the prevalence can only be expected with the eradication of infections. Accurate knowledge of the prevalence, histologic features, and causes is essential to achieve prevention and management of glomerular diseases in the tropics.

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.

Prevalence of seropositivity for hepatitis C virus in cataract patients and the general population

PURPOSE

To investigate the epidemiologic relationship between hepatitis C virus (HCV) infection and cataract.

SETTING

Yoshida Eye Clinic, Fukuoka, Japan.

METHODS

This study included 492 patients with age-related cataract and 2624 controls who had a municipal mass health screening. All subjects were 60 years or older and inhabitants of Chikugo City (population 45000), Fukuoka, Japan. Each subject was serologically tested for HCV using the third-generation enzyme immunoassay. Seropositivity was compared in subgroups consisting of patients by decade; that is 60 to 69 years of age, 70 to 79 years of age, and 80 to 90 years of age.

RESULTS

The prevalence of HCV in the cataract group and health-screening (control) group was 18.3% and 7.1%, respectively, in the 60- to -69 year subgroup; 17.8% and 6.6%, respectively, in the 70- to 79-year subgroup; and 15.1% and 3.7%, respectively, in the 80- to 90-year subgroup. In each subgroup, the prevalence of HCV was significantly higher in the cataract group than in the control group (P <.01, chi-square test). In the cataract group, the HCV seropositive and seronegative groups did not differ significantly in the prevalence of hepatitis B virus (P =.548, Fisher exact probability test).

CONCLUSIONS

Patients with age-related cataract had significantly higher seropositivity for HCV than an age-matched general population. This suggests that HCV infection may play a role in the development and/or progression of cataract.

Advances in therapy for hepatitis C infection

The first approved therapy for chronic hepatitis C virus (HCV) infection was recombinant interferon. Subsequently, controlled studies demonstrated that the combination of interferon-alpha and ribavirin leads to significantly higher virologic sustained responses in patients with chronic hepatitis C. A novel modification of the interferon molecule resulted in the formulation of pegylated interferons, which have a longer half-life than standard interferon. Two recent trials have established the superiority of pegylated interferons compared with interferon-alpha in inducing sustained virologic responses in patients with chronic HCV infection, with or without cirrhosis. Presumably, pegylated interferons will replace standard interferon in treating HCV infection. Phase 3 trials of pegylated interferons in combination with ribavirin are currently under way. Noninterferon-based therapies for the treatment of HCV infection are also in the developmental and experimental phases. Our aims in this review are to present the currently available therapeutic options for HCV infection and the evidence supporting their use in typical patients with chronic hepatitis C or in patients with special circumstances. We also briefly review novel therapeutic approaches, including noninterferon-based therapies.

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.

Influence of age and autoimmunity on liver disease in HCV-associated type II mixed cryoglobulinemia

It has been suggested that hepatitis C virus (HCV) infected patients with type II mixed cryoglobulinemia have less extensive liver damage than patients without cryoglobulinemia. We retrospectively evaluated 35 patients with type II mixed cryoglobulinemia associated with HCV infection, seeking for factors associated with normal alanine aminotransferase (ALT) values. The presence of anti-GOR and of other autoantibodies, including the recently described anti-LAG-3.1, was specifically investigated. Fifty-four percent of patients had anti-GOR, 46% anti-LAG-3.1, 40% anti-smooth muscle, 17% anti-nuclear, and 11% anti-liver-kidney microsome 1 antibodies. Anti-GOR was significantly (p = 0.037) associated with anti-LAG-3.1 but not with other autoantibodies. Persistently abnormal ALT levels were observed in 54% of patients. By univariate analyses, abnormal ALT was significantly associated with anti-GOR positivity (p = 0.018) and younger age (p = 0.03). Multivariate regression analysis confirmed that these variables were independently associated with abnormal ALT. Our data suggest that the presence of autoimmune manifestations as well as unidentified age-related host factor(s) may protect from liver injury in HCV-associated cryoglobulinemia.

Rheumatoid factors: host resistance or autoimmunity?

Rheumatoid factors (RFs), autoantibodies that bind to the Fc portion of IgG, are important in the immune response. RF-committed B-cells exist in the circulating lymphocyte pool in a high frequency (approximately 1-2 %) in normal individuals and in patients with pathological conditions associated with the sustained levels of circulating RF, such as rheumatoid arthritis (RA), Sjogren's syndrome (SS), and mixed cryoglobulinemia, associated with hepatitis C virus infection. RFs are induced by many infectious entities (viruses, bacteria, parasites) as a consequence of a secondary immune response to the pathogen, but usually the response is transient. It is likely that RFs play an important role in the host's defense against infection, both at the cellular level, where the RF B-cell can be an antigen presenting cell which can promote the antipathogen response, and at the humoral level, where RFs can contribute to the mopping up of the IgG antipathogen antibodies by contributing to immune complex formation and clearance. There has been much research on RFs in chronic pathological conditions, and the literature pertaining to their origin, structure, binding specificities, and possible roles in disease are discussed. The importance of the host defense, sometimes at the expense of an autoimmune response, is a balance that needs to be considered in light of a possible outcome of health or disease.

Cryoglobulinemia is a frequent cause of peripheral neuropathy in undiagnosed referral patients

Cryoglobulinemia represents an emerging cause of peripheral neuropathy, especially in Southern Europe, in view of its relationship with hepatitis C virus infection. In a series of 100 consecutive referral patients with uncharacterized peripheral neuropathies, we systematically investigated cryoglobulinemia to assess its diagnostic yield. The most frequent diagnosis was hereditary neuropathy (33%), 29% were acquired neuropathies of different types, and no cause could be identified in 27%. Cryoglobulinemic neuropathy was diagnosed in 11 patients (7 women and 4 men), aged 54-77 (mean = 63.5 years), most presenting with sensory polyneuropathy, often asymmetrical. Cryoglobulin was also detected in 2 additional patients in whom a final diagnosis of non-Hodgkin lymphoma was made. Purpura was absent in 4 patients (and in 2 with lymphoma), or restricted to discrete manifestations in the remaining patients, which did not provide a clue to the diagnosis. Thus, search for cryoglobulin proves useful in a substantial number of undiagnosed peripheral neuropathies (11% to 13% in our series), even in the absence of typical skin lesions, and it is recommended as a first-line investigation in patients with unexplained neuropathy presenting in middle to older age.

Diagnosis of liver nodules observed in chronic liver disease patients during ultrasound screening for early detection of hepatocellular carcinoma

OBJECTIVES

The aim of our study was to evaluate the nature of focal liver lesions detected during the ultrasound follow-up of a population (prevalently anti-hepatitis C virus [anti-HCV] positive) with chronic liver disease.

METHODS

The study population consisted of 1827 consecutive newly diagnosed chronic liver disease cases without liver nodules at enrollment. Patients were screened at 4-month intervals by ultrasound and serum alpha-fetoprotein assessment. All lesions detected on imaging studies (except those accompanied by diagnostic a-fetoprotein levels) were subjected to biopsy (histology and cytology).

RESULTS

During the 7-yr follow-up period (mean = 43.1 months), one or more solid focal lesions were found in 287 patients. a-Fetoprotein was diagnostic for hepatocellular carcinoma in 51 patients. Ultrasound-guided fine-needle biopsy was performed in the remaining 236 patients, yielding a diagnosis in 214: 198 hepatocellular carcinomas, 11 dysplastic nodules, and five B-cell non-Hodgkin's lymphomas (all confined to the liver and all in patients with chronic HCV infection). Twenty-two patients with nondiagnostic biopsies received diagnoses of hepatocellular carcinoma (20) or dysplastic nodules (two) based on arteriography or surgical biopsy.

CONCLUSIONS

Focal lesions arising in patients with HCV-related chronic liver disease can be other than hepatocellular carcinoma, and ultrasound-guided fine-needle biopsy plays an important role in their diagnosis. The prevalence of non-Hodgkin's lymphoma in this selected population was 0.31%. The fact that all five lymphoma patients had cirrhosis related to hepatitis C strengthens the hypothesis of an etiological correlation between the latter infection and B-cell lymphoproliferative disorders.

Cryoglobulinemia vasculitis

Cryoglobulins are immunogloblulins that persist in the serum, precipitate with cold temperature, and resolubilize when rewarmed. Mixed cryoglobulins, composed of different immunoglobulins, with a monoclonal component in type II and only polyclonal immunoglobulins in type III, are associated with connective tissue, malignant hematologic, or obvious infectious diseases. The syndrome of mixed cryoglobulinemia represents the consequence of an immune complex-type vasculitis. It is characterized by the clinical triad of purpura, arthralgia, and asthenia, and may involve numerous organs, particularly the peripheral nervous system and the kidneys. Mixed cryoglobulinemia frequently is associated with clinical and biologic evidence of liver disease. It seems fairly clear that mixed cryoglobulinemia is often a manifestation of underlying chronic active or persistent hepatitis. In the last 10 years, many studies have demonstrated that infection with hepatitis C virus is involved in the pathogenesis of most mixed cryoglobulinemia vasculitis. This review analyzes the main published data of hepatitis C virus-mixed cryoglobulinemia, the role of liver alterations, the predictive factors associated with mixed cryoglobulin production in hepatitis C virus patients and whether its character is symptomatic, and the different types of vasculitis associated with hepatitis C virus chronic infection and their treatments.

Long-term follow-up of a patient with cutaneous vasculitis secondary to mixed cryoglobulinaemia and hepatitis C virus

We describe the clinical course of a patient with mixed cryoglobulinaemia and multisystem disease over a 21-year period. She consistently tested negative for hepatitis C virus (HCV) serology, but active HCV infection (genotype Ia) was confirmed using reverse transcription-polymerase chain reaction. After initial improvement following treatment with interferon-alpha and ribavirin, unfortunately she developed severe neutropenia necessitating discontinuation of both drugs within 4 weeks. She died 1 month later.

Cryoglobulins

Serum cryoglobulins are found in a wide spectrum of disorders but are often transient and without clinical implications. Monoclonal cryoglobulins are usually associated with haematological disorders, whereas mixed cryoglobulins are found in many infectious and systemic disorders. So called essential mixed cryoglobulinaemia shows a striking association with hepatitis C virus (HCV) infection (> 90%). It is a systemic vasculitis (leucocytoclastic vasculitis) with cutaneous and multiple visceral organ involvement. Chronic HCV infection can lead to a constellation of autoimmune and neoplastic disorders. In this review, the aetiology, diagnosis, disease heterogeneity, and treatment of cryoglobulinaemia are discussed.

Interferon-alpha in combination with ribavirin as initial treatment for hepatitis C virus-associated cryoglobulinemic membranoproliferative glomerulonephritis

Mixed cryoglobulinemia (MC) and glomerulonephritis are the most important extrahepatic manifestations of chronic hepatitis C virus (HCV) infection. In HCV-infected patients with MC, renal involvement worsens the overall prognosis because of a high incidence of infection or cardiovascular disease. The relationship between MC and HCV infection has prompted the use of antiviral therapy. Two patients with chronic HCV infection, type-II MC and membranoproliferative glomerulonephritis (MPGN), presenting as nephrotic syndrome were treated with interferon (IFN)-alpha (3 MU 3 times per week) and ribavirin (15 mg/kg daily) for 6 months. Laboratory tests included measurement of anti-HCV antibodies, HCV RNA, and HCV genotyping, and characterization of circulating cryoglobulins. A pretreatment renal biopsy was performed, and the histopathologic lesions were scored according to the index of disease activity. Viremia and cryoglobulinemia were suppressed in both patients. However, a complete remission of proteinuria was observed in 1 patient only. The evaluation of the renal biopsy specimens revealed a mild MPGN (activity score: 5/24) in the patient with remission of proteinuria and a severe MPGN (activity score: 15/24) in the patient who maintained a nephrotic-range proteinuria. Although a fully satisfactory treatment is not yet available, we feel that a reasonable therapeutic strategy for HCV-infected patients with MC nephritis could be as follows: (1) antiviral treatment alone for patients with a low-grade kidney involvement, and (2) a short-term course of steroids and cytotoxic drugs followed by antiviral therapy for acute exacerbations and/or rapidly progressive GN.

Antibodies and vascular involvement in inflammatory joint disease: clinical relevance

The vascular endothelium is a common target of inflammatory joint disease. Autoimmune diseases including rheumatoid arthritis, systemic lupus erythematosus, and Sjögren's syndrome can be responsible for a spectrum of vascular disorders that encompasses vasculitis, thrombosis and/or atheroma associated with the antiphospholipid syndrome, and vascular damage caused by cryoglobulin deposition. These mechanisms can coexist, particularly in lupus patients. Joint disease is sometimes the presenting manifestation in primary vasculitis. Autoantibodies are detectable in most patients with vascular involvement and inflammatory joint disease. They are not merely markers for vascular involvement: in vitro and in vivo data suggest that some autoantibodies may contribute to the genesis of endothelial lesions, together with other factors. For instance, evidence of pathogenic effects has been found for antineutrophil cytoplasmic antibody (ANCA), most notably with antimyeloperoxidase or antiproteinase-3 specificity, in small-vessel vasculitides (Wegener's granulomatosis, Churg-Strauss syndrome, and microscopic polyangiitis); for immune complexes, particularly those containing cryoglobulins, in vasculitides secondary to CTDs; and for circulating anticoagulant and anticardiolipin antibodies, above all anti-beta2-glycoprotein I, in antiphospholipid syndrome. Antibodies to annexin V, modified lipoproteins, and endothelial cells may be of interest; their clinical relevance is unclear, however, and no standardized assays are available, so thatthese antibodies are not looked for in everyday practice. When deciding which antibody tests should be performed in a given patient, the circumstances surrounding the onset of the vasculopathy should be borne in mind. In patients with previous CTD, the tests are selected based on the diagnosis. In contrast, in a patient with no previous diagnosis, a vasculopathy can be either primary or secondary to undiagnosed CTD or to antiphospholipid syndrome: consequently, a broader array of tests is needed in this situation.