Extrahepatic manifestations associated with hepatitis C virus infection. A prospective multicenter study of 321 patients. The GERMIVIC. Groupe d'Etude et de Recherche en Medecine Interne et Maladies Infectieuses sur le Virus de l'Hepatite C

Thyroid disorders in chronic hepatitis C

PURPOSE

To explore the association of hepatitis C virus (HCV) infection with thyroid disorders.

METHODS

We investigated the prevalence of thyroid disorders in 630 consecutive patients with chronic hepatitis due to HCV infection; all patients were free of cirrhosis and hepatocarcinoma, and were not on interferon treatment. Also included were a control group of 389 subjects from an iodine-deficient area, another control group of 268 persons living in an area of iodine sufficiency, and 86 patients >40 years of age with chronic hepatitis B. Levels of thyroid-stimulating hormone (TSH), free thyroxine (T(4)), and triiodothyronine (T(3)), as well as anti-thyroglobulin and anti-thyroid peroxidase antibodies, were measured.

RESULTS

Mean TSH levels were higher (P = 0.001), and free T(3) and free T(4) levels were lower (P <0.0001), in patients with chronic hepatitis C than in all other groups. Patients with chronic hepatitis C were more likely to have hypothyroidism (13% [n = 82]), anti-thyroglobulin antibodies (17% [n = 108]), and anti-thyroid peroxidase antibodies (21% [n = 132]) than were any of the other groups.

CONCLUSION

Both hypothyroidism and thyroid autoimmunity are more common in patients with chronic hepatitis C-even in the absence of cirrhosis, hepatocellular carcinoma, or interferon treatment-than in normal controls or those with chronic hepatitis B infection.

Influence of antiviral therapy in hepatitis C virus-associated cryoglobulinemic MPGN

BACKGROUND

The influence of hepatitis C virus (HCV) treatment on the course of HCV cryoglobulinemic membranoproliferative glomerulonephritis (MPGN) is controversial.

METHODS

Twenty-five patients with nephrotic-range proteinuria, mixed cryoglobulinemia, MPGN proved by renal biopsy, and HCV infection were studied for their response to antiviral treatment.

RESULTS

After first-line treatment with prednisone, furosemide, or plasmapheresis, antiviral therapy with standard or pegylated interferon alfa and ribavirin was introduced in 18 patients. These patients were compared with 7 patients who did not receive antiviral treatment. Mean duration of antiviral treatment was 18 +/- 10 months, with a follow-up of at least 6 months after treatment withdrawal. HCV RNA clearance (sustained virological response) was achieved in 12 of 18 patients. Compared with values before antiviral therapy, a decrease in proteinuria was observed in sustained virological responders at the end of combination therapy, as well as at the end of follow-up (mean, 2.85 +/- 2.2 [SD] versus 1 +/- 1.4 and 0.4 +/- 0.8 g/d, respectively; P < 0.05). In sustained virological responders, cryoglobulin levels at the end of treatment (0.29 +/- 0.4 g/L) and end of follow-up (0.25 +/- 0.4 g/L) were decreased (P < 0.05) compared with pretreatment values (1.38 +/- 2.2 g/L). Conversely, no changes in serum cryoglobulinemia levels were observed in nonresponders or controls. Serum creatinine levels remained stable in the 18 patients with antiviral therapy, regardless of response to treatment.

CONCLUSION

Anti-HCV treatment improved HCV-associated cryoglobulinemic glomerulonephritis.

Relapsing polychondritis, chronic hepatitis C virus infection, and mixed cryoglobulemia

OBJECTIVE

Review of relapsing polychondritis (RP) and its association to chronic hepatitis C virus (HCV) infection and mixed cryoglobulinemia.

METHODS

A case of RP associated with HCV infection is reported. The English language medical and scientific literature was reviewed for RP, hepatitis C, and its relation to other connective tissue diseases from February 1966 to January 2003 using MEDLINE.

RESULTS

RP is an uncommon, multisystem disease of unknown etiology characterized by recurrent inflammation of cartilaginous and related tissues, being associated with other diseases in 30% to 35% of cases. HCV infection is a systemic illness with a propensity to trigger or exacerbate autoimmune disorders: eg, essential mixed cryoglobulinemia, membranoproliferative glomerulonephritis, and leukocytoclastic and systemic vasculitis. We could find no previous report of an association between RP with HCV and mixed cryoglobulinemia. Treatment with interferon gamma and ribavirin (IR) not only induced an undetectable viral load, but also resolved symptoms of RP.

CONCLUSIONS

We report a patient with RP, HCV, and mixed cryoglobulinemia. It is unknown if there is a cause-effect or chance relationship. Treatment with IR improved the symptoms of RP. It is not known whether the effects of IR were directly on the RP or suppressed RP indirectly through the actions on the viral load or active hepatitis.

The case for hepatitis C arthritis

OBJECTIVE

To present the data available supporting the existence of an arthropathy associated with hepatitis C infection.

METHODS

The MEDLINE database was searched for "arthritis" intersecting with "hepatitis C" in addition to the authors' investigations and experience on this subject.

RESULTS

Arthritis, not otherwise explained, has been noted in 2% to 20% of hepatitis C virus (HCV) patients. This arthritis is rheumatoid-like in two thirds of the cases and a waxing/waning oligoarthritis in the rest. Cryoglobulinemia alone does not explain the arthritis, and there is difficulty in differentiating it from rheumatoid arthritis. The arthropathy is nonerosive/nondeforming. Whereas nonsteroidal anti-inflammatory drugs, low-dose corticosteroids, and hydroxychloroquine may be helpful, conventional treatment of arthritis may be problematic in the context of viral hepatitic arthropathy. Antiviral therapy is most effective, even without viral clearance, but rheumatic complications may ensue.

CONCLUSIONS

HCV arthropathy should be considered in the differential diagnosis of new-onset arthritis.

[A pluridisciplinary point of view of hepatitis C virus infections]

Various complementary actors are implied in the management of HCV infections: virologists, general practitioners, hepato-gastroenterologists and hospital residents, and they should all cooperate together. The role of biologist is crucial in assisting the practitioners in the choice of examinations to be prescribed for the diagnosis of HCV infections (search for RNA HCV), in establishing a prognosis and in deciding on the therapeutic strategy (genotyping, Fibrotest and Actitest). The role of the general practitioner is important at all stages of the management. The practitioner's involvement is also crucial in the recognition and follow-up of the concomitant diseases. THE ROLE OF THE SPECIALIST: The hepatologist, together with the general practitioner, are inseparable partners in the management of a patient suffering from hepatitis C. The specialist should only see patients exhibiting hepatitis C who are participating in a treatment program, since the indication for treatment is usually decided on by the specialist. The hepatologist should be informed of the various concomitant diseases and the treatments (replacement therapy or others) prescribed for them. CRUCIAL QUESTIONS: For the management of an HCV infection, in general 3 questions require an answer: who should be screened for such infections, what explorations should be performed in the case of positive serology and what follow-up is required during and after anti-HCV treatment?

Severe hemolytic anemia due to cold agglutinin complicating untreated chronic hepatitis C: efficacy and safety of anti-CD20 (rituximab) treatment

Autoimmune hemolytic anemia (AIHA) is rare and difficult to treat during chronic hepatitis C. We report herein the case of a hepatitis C patient with severe and resistant AIHA who experienced a good and sustained response with anti-CD20 monoclonal antibody treatment.

Hepatitis C Infection: A Clinical Review

Nearly three million persons in the United States are viremic with hepatitis C (HCV). Despite a decreasing incidence of HCV in this country, the prevalence of HCV-related chronic liver disease is increasing. Most infections in the United States are acquired by intravenous drug use. The chronicity rate of HCV is high, reaching 85% in some populations, and the risk of progression to advanced liver disease is as high as 20% within twenty years of infection. Host factors like alcohol use accelerate the rate of progression. The enzyme immunoassay is the preferred initial test for diagnosis; the third generation assay has greater than a 99% specificity in immunocompetent patients. Barring contraindications, the standard of care for treatment of chronic HCV has become pegylated interferon and ribavirin. With this therapy, the cure rate for treatment-naïve patients is about 55%, but rates are higher in certain groups. Common side effects of therapy include neuropsychiatric symptoms, influenza-like symptoms and hematological abnormalities.

Role of anti-cyclic citrullinated peptide antibodies in discriminating patients with rheumatoid arthritis from patients with chronic hepatitis C infection-associated polyarticular involvement

This study was performed to assess the utility of anti-cyclic citrullinated peptide (anti-CCP) antibodies in distinguishing between patients with rheumatoid arthritis (RA) and patients with polyarticular involvement associated with chronic hepatitis C virus (HCV) infection. Serum anti-CCP antibodies and rheumatoid factor (RF) were evaluated in 30 patients with RA, 8 patients with chronic HCV infection and associated articular involvement and 31 patients with chronic HCV infection without any joint involvement. In addition, we retrospectively analysed sera collected at the time of first visit in 10 patients originally presenting with symmetric polyarthritis and HCV and subsequently developing well-established RA. Anti-CCP antibodies and RF were detected by commercial second-generation anti-CCP2 enzyme-linked immunosorbent assay and immunonephelometry respectively. Anti-CCP antibodies were detected in 23 of 30 (76.6%) patients with RA but not in patients with chronic HCV infection irrespective of the presence of articular involvement. Conversely, RF was detected in 27 of 30 (90%) patients with RA, 3 of 8 (37.5%) patients with HCV-related arthropathy and 3 of 31 (9.7%) patients with HCV infection without joint involvement. Finally, anti-CCP antibodies were retrospectively detected in 6 of 10 (60%) patients with RA and HCV. This indicates that anti-CCP antibodies can be useful in discriminating patients with RA from patients with HCV-associated arthropathy.

Serum anti-cholesterol antibodies in chronic hepatitis-C patients during IFN-alpha-2b treatment

Previously we detected more than 3 times higher anti-cholesterol antibody (ACHA) levels in HIV positive patients compared to healthy individuals, however, this level significantly decreased during highly active anti-retroviral therapy (HAART). In our present study we examined whether these findings could also be detected in patients with chronic hepatitis C (CHC). We calculated the correlation between the ACHA levels and the C5b-9 complement activation product. 39 patients with CHC were treated with IFN-alpha-2b (Schering-Plough) 5 MU daily for 6 weeks, followed by 5 MU TIW. Serum levels of ACHA and complement activation products were measured with ELISA. Serum HCV RNA was measured by a highly sensitive branched DNA technique before and 3, 6 and 12 months after the beginning of IFN-alpha-2b therapy. 52 healthy persons served as controls. At the onset of treatment ACHA level was significantly (p = 0.0062) higher in patients (40 (24-69) AU/ml) (median (interquartile range)) than in control sera (26 (20-35) AU/ml). In the 26 responder patients ACHA levels decreased to the normal level during the therapy, but no change was observed in the 13 non-responders. In patients with a sustained response ACHA levels remained low till the end of the 12 months IFN treatment. ACHA levels were significantly (p = 0.0422) higher in the patients with low (< 4.0 mmol/l) than in those with normal (> or = 4.0 mmol/l) cholesterol concentrations. The ACHA level before the therapy strongly correlated (r = 0.5499, p = 0.0014) with C5b-9 serum levels. ACHA levels are elevated in CHC, but this elevation is not as high as in HIV. Decrease of viral load by IFN-alpha-2b treatment in the responders results in normalization of ACHA concentration. High ACHA levels in patients with low serum cholesterol concentration suggest that high ACHA levels may contribute to the decrease in cholesterol levels. The correlation between the ACHA and C5b-9 levels indicate, that the ACHA may play a role in the complement activation in CHC.

[Extrahepatic manifestations of hepatitis C virus infection]

<zakljucak> Hepatitis C virusna infekcija je zaista povezana sa sirokim spektrom ekstrahepatickih sindroma. Neke bolesti su sigurno povezane sa HCV infekcijom (krioglobulinemija, kasna kozna porfirija, membranoproliferativni glomerulo-nefritis), za neke postoji velika verovatnoca (autoimunske bolesti stitaste zlezde, autoimunska trombocitopenija, limfomi, secerna bolest neuropatije, artritis, lihen planus, nodozni poliarteritis, sijaloedenitis sindrom fibromialgije) dok se za neke bolesti ostavlja mogucnost da se radi o slucajnoj udruzenosti za sto su potrebna nova istrazivanja.

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 of hepatitis C virus infection in porphyria cutanea tarda: systematic review and meta-analysis

BACKGROUND/AIMS

To conduct a systematic review and meta-analysis on the prevalence of hepatitis C virus (HCV) infection in porphyria cutanea tarda (PCT).

METHODS

Studies evaluating prevalence of HCV infection in patients with PCT were considered. Bibliographical searches were conducted in several electronic databases. Studies comparing HCV prevalence in PCT (cases) and in a reference group (controls) were included in the meta-analysis, combining the Odds Ratios (OR) of the individual studies.

RESULTS

Fifty studies including 2,167 patients were identified. Mean HCV prevalence by serology was 47%, and 50% with polymerase chain reaction (PCR). HCV prevalence markedly varied depending on the country and the type of PCT (57% in the sporadic and 26% in the familial form). Eight case-control studies were identified. Seven studies compared HCV prevalence in PCT vs. healthy controls: 40% vs. 0.24%, respectively (OR=275; 95% confidence interval=104-725). Heterogeneity disappeared when only studies evaluating HCV infection by PCR were included.

CONCLUSIONS

HCV prevalence in patients with PCT is approximately 50%, much higher than that reported in general population, suggesting a possible etiopathogenic role of HCV in PCT. The striking geographical variation in this association suggests that genetic and/or environmental factors may also be involved in the pathogenesis of this disorder.

Peripheral neuropathy in hepatitis C virus infection with and without cryoglobulinaemia

OBJECTIVES

Hepatitis C virus (HCV) infection is often associated with cryoglobulinaemia (CG). Peripheral neuropathy (PN) is a comparatively common complication of CG associated with HCV infection and it is thought to be attributable to nerve ischaemia. Only few HCV CG patients with PN have been reported. The recent finding of HCV RNA in nerve biopsy specimens has suggested a possible direct role of HCV in the pathogenesis of PN. The authors studied 51 HCV patients to determine the prevalence of CG and to clarify the possible mechanism by which HCV determines the PN.

METHODS

All the patients were studied clinically, by laboratory tests and electrophysiologically. Twenty eight patients underwent sural nerve biopsy where both morphological and morphometric evaluation of the biopsy specimen was performed, as well as statistical analysis.

RESULTS

CG was found in 40 of 51 cases (78%). Polyneuropathy was significantly prevalent in CG+ patients compared with CG- (18 of 40 compared with 1 of 11 patients; p=0.01). HCV CG- patients more frequently developed well defined mononeuropathy or multiple neuropathy when compared with HCV CG+ (10 of 11 compared with 22 of 40; p<0.03). HCV CG+ patients showed significantly higher proportion of rheumatoid factor positivity (p<0.001) and low C4 levels (p=0.001). Nerve biopsy was performed in 25 of 40 HCV CG+ patients and in 3 of 11 HCV CG- patients: epineurial vasculitis was present in 8 of 25 HCV CG+ (32%) and in 2 of 3 HCV CG-. Differential fascicular loss of axons was found in 10 of 25 CG+ (40%) and 1 of 3 CG-, signs of both demyelination and axonal degeneration were present in 7 of 25 CG+ (28%). No significant difference was found in neuropathological features, while histometrical analysis disclosed more severe involvement in CG+ patients.

CONCLUSIONS

These findings suggest that the presence of CG is a negative predictive factor for the associated PN. Morphological findings in the sural nerve from HCV CG- and CG+ are consistent with an ischaemic mechanism of nerve damage and are against a direct role of the virus in causing the associated PN.

Oral diseases possibly associated with hepatitis C virus

Morbidity associated with hepatitis C virus (HCV) infection can involve a variety of extrahepatic conditions, including lichen planus (LP) and sialadenitis, predominantly or exclusively involving the oral region, conditions which have been largely neglected in reviews. The literature suggests that HCV-infected patients may frequently have Sjögren-like sialadenitis with mild clinical symptoms, whereas oral LP may be significantly associated with HCV infections in Southern Europe and Japan but not in Northern Europe. These geographical differences could be related to immunogenetic factors such as the HLA-DR6 allele, significantly expressed in Italian patients with OLP and HCV. Analysis of experimental data suggests that HCV could be involved in the pathogenesis of both these diseases. Moreover, parotid lymphoma may arise in patients with sialadenitis, mainly with type II cryoglobulinemia. Little attention has been paid to oral health needs in HCV-infected patients and the variable effect of interferon-alpha therapy on oral tissues. Further research is needed, because of the potentially great influence of oral diseases possibly linked to HCV on the quality of life of millions of patients.

Rheumatic manifestations of hepatitis C infection

Among chronic viral infections, hepatitis C virus (HCV) infection is uniquely associated with an array of rheumatic manifestations and autoimmune laboratory findings. These include, among others, arthralgias, arthritis, fatigue, fibromyalgia, vasculitis, and sialadenitis (Sjögren-like). The mechanisms that are involved in the pathogenesis of these diverse manifestations have not yet been clarified. Regardless of the direct or indirect pathogenetic role of HCV in these clinical entities, the concomitant presence of a chronic viral infection creates a number of diagnostic and therapeutic problems. This is particularly true when immunosuppressive therapy is needed for control of disease activity (eg, HCV-associated cryoglobulinemic vasculitis). The emerging treatment options for chronic HCV offer a major chance for viral eradication and conceivably for cure of these HCV-associated conditions. In this review, the recent advances in the epidemiology, pathogenesis, clinical findings, and treatment of HCV-associated rheumatic conditions are presented.

Antiphospholipid antibodies and infections

Many infections have been found to be associated with antiphospholipid antibodies (aPL), although a pathogenic role for these antibodies has not usually been obvious except in a few isolated cases. Two types of aPL have been referred to as "autoimmune" and "infectious" types. This distinction, however, has subsequently been found not to be absolute.

Autoantibodies to CD69 in patients with chronic hepatitis type C: a candidate marker for predicting the response to interferon therapy

OBJECTIVE

To understand the autoimmunity associated with chronic hepatitis C (CHC), we investigated autoantibodies (autoAbs) to CD69.

METHODS

With this aim, we tested the reactivity of serum samples from patients with CHC and asymptomatic carriers of hepatitis C virus (HCV), as well as from patients with chronic hepatitis B (CHB) and autoimmune hepatitis (AIH), to recombinant CD69 molecules.

RESULTS

Frequencies of anti-CD69 autoAbs were 38.7% in CHC, 15.8% in AIH and 12.3% in CHB. None of the tested asymptomatic HCV carriers had autoAbs to CD69. It is important clinically that the presence of anti-CD69 autoAbs was found to be associated with a poor response to interferon-alpha (IFN-alpha) therapy. In the epitope analysis, multiple epitopes were mapped on CD69, indicating antigen-driven production of the autoAbs.

CONCLUSION

We evidenced existence of anti-CD69 autoAbs in patients with CHC, and found that the anti-CD69 autoAb may have potential for predicting responses to IFN-alpha therapy.

Extrahepatic manifestations of hepatitis C infection

Hepatitis C virus (HCV) affects 1.8% of the American population, and approximately 38% of patients with HCV will manifest symptoms of at least 1 extrahepatic manifestation during the illness. Renal disease, neuropathy, lymphoma, and Sjögren syndrome with or without mixed cryoglobulinemia are all strongly associated with HCV infection. Porphyria cutanea tarda and diabetes have also been linked to HCV. Most extrahepatic manifestations of chronic HCV infection are immunological, and the chronic infection seems to be necessary for their development. The molecular study of the unique way in which the HCV virus interacts with the human immune system is beginning to provide plausible explanations of the pathogenic role of HCV in some of these syndromes, but many pathogenetic links remain completely obscure.

Anti-cardiolipin antibodies in patients with chronic viral hepatitis are independent of beta2-glycoprotein I cofactor or features of antiphospholipid syndrome

BACKGROUND

Although controversial, some authorities have implicated hepatitis C virus (HCV) as a cause of anti-phospholipid syndrome (APLS). Anti-cardiolipin antibodies (anti-CLAbs) in APLS are cofactor-dependent ('pathogenic' antibodies). We conducted a study in order to determine the prevalence of anti-CLAbs in HCV patients, and furthermore to address whether these autoantibodies are cofactor-dependent or not and whether they are associated with features of APLS. Patients with hepatitis B virus (HBV) were also evaluated in order to assess whether there are differences in the prevalence and the clinical significance of anti-CLAbs between these two major types of chronic viral hepatitis.

MATERIALS AND METHODS

One hundred and seventy-four consecutive HCV patients, 50 HBV patients and 267 healthy were investigated for the presence of anti-CLAbs and antibodies against beta2-glycoprotein I (beta2-GPI), which is the most important cofactor of the 'pathogenic' anti-CLAbs in APLS. IgG anti-CLAbs were determined by an in-house quantitative ELISA and anti-beta2-GPIAbs using a commercial ELISA kit.

RESULTS

21.3% of the HCV and 14% of the HBV patients tested positive for IgG anti-CLAbs (P < 0.0001 compared with healthy controls). Neither age, sex, certain epidemiologic and laboratory parameters nor the clinical status and the histologic findings were associated with anti-CLAbs detection in both diseases. 2.3% of the HCV (P < 0.05 compared with healthy controls) and 2% of the HBV patients tested positive for anti-beta2-GPIAbs. Presence of anti-CLAbs was not associated with features of APLS.

CONCLUSIONS

A significant proportion of the HCV and HBV patients had detectable IgG anti-CLAbs. However, the anti-CLAbs titres were relatively low, and in most cases seem to be cofactor-independent ('nonpathogenic'). The latter is further supported by the lack of their association with clinical features of APLS. Furthermore, anti-CLAbs appear to be detected irrespective of the demographic, laboratory, clinical and histologic status in both HCV and HBV. However, prospective studies of longer duration may be required in order to address whether anti-CLAbs in patients with chronic viral hepatitis are or are not of clinical importance.

Lower expression of CD81 B-cell receptor in lymphoproliferative diseases associated with hepatitis C virus infection

Chronic hepatitis C virus (HCV) infection is frequently associated with type II mixed cryoglobulinaemia (MC), a benign lymphoproliferative disease (LPD). More recently, HCV has been implicated as a possible aetiologic factor of B-cell non-Hodgkin lymphoma (B-NHL). CD81, a B-cell surface receptor, has been proposed as a receptor for HCV binding and entry in circulating B cells. The stimulation of CD81 complex enables B cells to respond to lower concentrations of antigen and finally induces B-cell proliferation. We studied the phenotypic expression of CD81, CD19 and CD5 on circulating B cells in HCV patients LPD-positive or LPD-negative. Sixty-two patients were anti-HCV antibody positive. Among HCV positive patients, 44 were HCV RNA positive with an histologically proven chronic active hepatitis of whom 10 had a B-NHL, 14 an MC and 24 no extrahepatic manifestation. Eighteen patients were HCV RNA negative with evidence of resolved infection. A control group included 40 healthy subjects. Peripheral blood mononuclear cells (PBMC) were stained for surface expression of CD81, CD19 and CD5 using monoclonal antibodies, and were analyzed by flow cytometry. The percentage of PBMC expressing CD81, CD19 and CD5 receptors were compared between the groups by univariate analysis. Logistic regression model variables were then evaluated to correlate the presence of an LPD with HCV infection characteristics (i.e. age, gender, genotype, duration of infection, HCV RNA positivity, liver histological lesions), or phenotypic expression of CD81, CD19 and CD5 receptors on PBMC. HCV antibody-positive compared with HCV-negative subjects had a higher expression of CD19 receptor (23 +/- 13 vs 13 +/- 1%, P = 0.003). Among HCV RNA positive-patients, LPD+ compared with LPD- patients had a lower expression of CD81 (58 +/- 28 vs 82 +/- 18%, P = 0.001) and CD5 receptor (66 +/- 16 vs 74 +/- 13%, P = 0.04). In multivariate analysis, the expression of CD81 receptor was a negative (OR = 0.15, 95% CI = 0.04-0.64, P = 0.01) and CD19 receptor a positive (OR = 4.81, 95% CI =1.29-17.88, P = 0.02) predictive factor for an LPD. We found two negative predictive factors for HCV RNA positivity, i.e. age (OR = 0.23, 95% CI. = 0.08-0.62, P = 0.003) and the expression of CD81 receptor (OR = 0.34, 95% CI = 0.13-0.89, P = 0.02). In patients with a chronic active HCV infection, the presence of a lymphoproliferative disease, either MC or B-NHL, is associated with lower expression of CD81 and higher expression of CD19 receptor on peripheral B cells.

Ocular manifestations of hepatitis C virus infection

Approximately 3.6 million persons in the United States are infected with the hepatitis C virus (HCV), a condition with both hepatic and extrahepatic sequelae. Although no pathognomonic manifestation of HCV infection in the eye has been demonstrated, associations between HCV infection and various ocular syndromes have been reported in small case series and individual patients. At this time, the ocular manifestations of HCV infections best supported by the literature include a dry eye syndrome similar to Sjögren syndrome, and ischemic retinopathy caused by either an HCV-induced vasculitis or treatment with interferon. Patients with diabetes seem to be more susceptible to interferon retinopathy and to subsequent permanent visual loss. There have been no cases of HCV transmission via corneal transplantation, suggesting that current cadaveric screening protocols are effective in preventing this route of transmission. Screening for HCV should be considered in patients with risk factors for HCV infection who suffer from unexplained ischemic retinopathy or dry eyes.

Interferon-alpha and ribavirin treatment in patients with hepatitis C virus-related systemic vasculitis

OBJECTIVE

Hepatitis C virus (HCV)-related vasculitis may involve multiple organs, including the skin, kidneys, and nervous system, and may be life-threatening. Although HCV is increasingly recognized as a cause of systemic vasculitis, limited data are available regarding the optimal treatment of this potentially serious condition. Therefore, we retrospectively analyzed the response to treatment in patients with chronic hepatitis C complicated by systemic vasculitis who had received antiviral therapy with interferon-alpha (IFNalpha) and ribavirin.

METHODS

This retrospective study included 27 patients with systemic vasculitis and chronic HCV infection. Each patient had received treatment with IFNalpha and ribavirin for at least 6 months. The response to antiviral treatment was analyzed by comparing clinical, immunologic, and virologic data at the time of entry and during followup. Clinical response was defined according to the evolution of weight, arthralgia, nervous system, renal system, and cutaneous involvement. The virologic and immunologic responses were defined by the absence of HCV RNA and the absence of cryoglobulinemia, respectively, both 6 months after stopping antiviral therapy and at the end of followup.

RESULTS

Patients received IFNalpha for a mean +/- SD of 20 +/- 14 months and ribavirin (at a mean +/- SD dosage of 895 +/- 250 mg/day) for 14 +/- 12 months. Other treatments included low-dose corticosteroids and plasma exchange. After a mean +/- SD followup of 57 +/- 29 months, 25 of 27 patients are alive and are being followed up as outpatients. Because of the heterogeneity of anti-HCV treatments received, the main results were stratified according to patients with 6 months of followup after stopping antiviral treatment (group 1, n = 14) and those who were still undergoing antiviral therapy at the time of analysis (group 2, n = 13). Nine patients in group 1 had a sustained virologic response and were clinical and immunologic complete responders. Four patients in group 1 were virologic nonresponders, and 3 of these patients had partial clinical and immunologic responses. Overall, 10 patients in group 1 had a complete clinical and immunologic response of their vasculitis (all 9 of the sustained virologic responders and 1 of the 5 patients who remained viremic). At the end of followup, 7 patients in group 2 were negative for HCV RNA; 6 were complete clinical responders. Among the other 6 patients in group 2, who had persistent viremia, 4 had a partial clinical response. Among the patients in group 1, HCV RNA was more often undetectable and genotype 1 was less frequent in complete clinical responders compared with partial/nonresponders. Age, sex, clinical vasculitic involvement, mean duration or total cumulative dose of IFNalpha or ribavirin, and use of steroids or plasmapheresis did not differ significantly according to clinical response.

CONCLUSION

Treatment with IFNalpha and ribavirin can achieve a complete clinical response in most patients with HCV-related systemic vasculitis. Complete clinical response correlates with the eradication of HCV.

Course and outcome of hepatitis C

The hepatitis C virus (HCV) is a small enveloped RNA virus belonging to the family flaviviridae and genus hepacivirus. The HCV RNA genome is 9,600 nucleotides in length and encodes a single polyprotein that is post-translationally cleaved into 10 polypeptides including t3 structural (C, E1, and E2) and multiple nonstructural proteins ([NS] NS2 to NS5). The NS proteins include enzymes necessary for protein processing (proteases) and viral replication (RNA polymerase). The virus replicates at a high rate in the liver and has marked sequence heterogeneity. There are 6 genotypes and more than 90 subtypes of HCV, the most common in the United States being 1a and 1b (approximately 75%), 2a and 2b (approximately 15%), and 3 (approximately 7%). Acute hepatitis C is marked by appearance of HCV RNA in serum within 1 to 2 weeks of exposure followed by serum alanine aminotransferase (ALT) elevations, and then symptoms and jaundice. Antibody to HCV (anti-HCV) tends to arise late. In acute resolving hepatitis, HCV RNA is cleared and serum ALT levels fall to normal. However, 55% to 85% of patients do not clear virus, but develop chronic hepatitis C. Chronic hepatitis C is often asymptomatic, but is usually associated with persistent or fluctuating elevations in ALT levels. The chronic sequelae of hepatitis C include progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Extra-hepatic manifestations include sicca syndrome, cryoglobulinemia, glomerulonephritis, and porphyria cutanea tarda. Knowledge of the course and outcome of hepatitis C is important in developing approaches to management and therapy.

Course and outcome of hepatitis C

The hepatitis C virus (HCV) is a small enveloped RNA virus belonging to the family flaviviridae and genus hepacivirus. The HCV RNA genome is 9,600 nucleotides in length and encodes a single polyprotein that is post-translationally cleaved into 10 polypeptides including t3 structural (C, E1, and E2) and multiple nonstructural proteins ([NS] NS2 to NS5). The NS proteins include enzymes necessary for protein processing (proteases) and viral replication (RNA polymerase). The virus replicates at a high rate in the liver and has marked sequence heterogeneity. There are 6 genotypes and more than 90 subtypes of HCV, the most common in the United States being 1a and 1b (approximately 75%), 2a and 2b (approximately 15%), and 3 (approximately 7%). Acute hepatitis C is marked by appearance of HCV RNA in serum within 1 to 2 weeks of exposure followed by serum alanine aminotransferase (ALT) elevations, and then symptoms and jaundice. Antibody to HCV (anti-HCV) tends to arise late. In acute resolving hepatitis, HCV RNA is cleared and serum ALT levels fall to normal. However, 55% to 85% of patients do not clear virus, but develop chronic hepatitis C. Chronic hepatitis C is often asymptomatic, but is usually associated with persistent or fluctuating elevations in ALT levels. The chronic sequelae of hepatitis C include progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Extra-hepatic manifestations include sicca syndrome, cryoglobulinemia, glomerulonephritis, and porphyria cutanea tarda. Knowledge of the course and outcome of hepatitis C is important in developing approaches to management and therapy.

Viral etiopathogenesis of Sjögren's syndrome: role of the hepatitis C virus

Patients with hepatitis C virus (HCV) chronic infection present some extrahepatic manifestations that may mimic the clinical, immunologic and histological manifestations of primary Sjögren's syndrome (SS). Thus, HCV patients with sicca symptomatology and positive autoantibodies could be misdiagnosed as a 'primary' SS. Nevertheless, there are several clinical and immunologic features that could help us differentiate both processes.

Th1/Th2 cytokine imbalance in patients with Sjögren syndrome secondary to hepatitis C virus infection

OBJECTIVE

To investigate if the serum immunologic profile, as delineated by serum circulating levels of Th1/Th2 cytokines and autoantibodies, is different in patients with Sjögren syndrome (SS) with and without hepatitis C virus (HCV) infection.

METHODS

This study included 20 patients with HCV-related SS and 47 consecutive patients with primary SS. All fulfilled 4 or more of the modified 1996 European criteria for SS. Serum levels of interleukin (IL)-2 (pg/mL), srIL-2 (pM), tumor necrosis factor (TNF)-alpha (pg/mL), IL-6 (pg/mL), and IL-10 (pg/mL) were determined using enzyme immunoassay. We also analyzed the following immunologic tests: anti-nuclear antibodies (ANA), anti-mitochondrial antibodies (AMA), anti-parietal cell antibodies (PCA), anti-smooth muscle antibodies (SMA), anti-liver-kidney microsome antibodies type-1 (LKM-1), anti-Ro/SS-A, anti-La/SS-B, rheumatoid factor (RF), complement factors (C3 and C4), and cryoglobulins.

RESULTS

Of the 20 patients with HCV-related SS, 18 were women and 2 men (mean age, 66 years). Patients with HCV-related SS had a different cytokine profile compared with patients with primary SS, with higher circulating levels of IL-6 (73.6 v 33.0 pg/mL, P =.045), IL-10 (6.7 v 3.1 pg/mL, P =.01), srIL-2 (124.6 v 72.7 pM, P =.001), and TNF-alpha (59.8 v 31.7 pg/mL, P =.003). The main immunologic features were ANA, detected in 75% of patients, RF in 63%, cryoglobulinemia in 50%, hypocomplementemia in 40%, SMA in 30%, PCA in 25%, anti-Ro/SS-A in 25%, AMA in 20% and anti-La/SS-B in 16%. When compared with primary SS patients, those with HCV-related SS had a higher prevalence of AMA (20% v 2%, P =.025), hypocomplementemia (40% v 11%, P =.015), and cryoglobulinemia (50% v 12%, P =.003).

CONCLUSION

Although chronic HCV infection may mimic the main clinical, histologic and immunologic features of primary SS, patients with HCV-related SS showed some differentiated characteristics, including a predominant Th2 pattern and a higher frequency of cryoglobulinemia and hypocomplementemia (features closely related to HCV). This suggests that the SS observed in some HCV patients should be interpreted as one of the extrahepatic manifestations of chronic HCV infection.

Prevalence of hepatitis C virus infection in patients with rheumatoid arthritis

BACKGROUND

Various viruses have been implicated in the cause and pathogenesis of rheumatoid arthritis (RA). Hepatitis C virus (HCV) infection, which has been recognised as a cause of some autoimmune diseases, and which has been described as sometimes presenting with rheumatic manifestations indistinguishable from RA, might be a candidate.

OBJECTIVE

To evaluate the prevalence of HCV infection in patients with RA.

METHODS

Consecutive patients with RA admitted to hospital in two departments of rheumatology were prospectively studied. Patients' serum samples were screened for the presence of anti-HCV antibodies. Patients with positive serology were further evaluated for the presence of HCV ribonucleic acid by reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

309 patients (232 women, 77 men, mean age (SD) 54.1 (14.8) years) were studied. Their mean (SD) disease duration was 74.1 (91) months. Tests for rheumatoid factors and antinuclear antibodies were positive in 213 (69%) and 114 (37%) of the patients respectively. Systemic vasculitis was found in 12 (4%) of the patients. Mean erythrocyte sedimentation rate was 36.4 (SD 30.5) mm at the first hour (normal <10 mm) and C reactive protein was 36.8 (SD 45.8) mg/l (normal range <5 mg/l), respectively, with 181(58.6%) of patients considered as having active disease. Aspartate transaminases were increased in 14 (4%) patients, and alkaline phosphatase in 14 (4%). A positive anti-HCV serology was found in two (0.65%) patients, including one with a previously diagnosed HCV infection. HCV RNA was positive by RT-PCR in one of those two patients.

CONCLUSION

A 0.65% prevalence of past or active HCV infection was found in patients with RA, which did not differ from the prevalence of HCV in the general French population. This result does not support the participation of HCV infection in the pathogenesis of RA.

Peripheral blood count abnormalities among patients with hepatitis C in the United States

An estimated 2.7 million people in the United States are infected with the hepatitis C virus (HCV), yet the influence of HCV infection on the peripheral blood count remains unknown. To investigate the prevalence of low peripheral blood counts among HCV-infected adults in the United States general population, we analyzed data collected in the third National Health and Nutrition Examination Survey (NHANES III). The study population consisted of 16,196 individuals age 18 or older who had peripheral blood counts and data on HCV infection. The lowest fifth percentile of each component of the peripheral blood was designated a priori as being low. HCV infection was assessed by antibody reactivity. HCV antibody-positive individuals were 3-fold more likely to have low neutrophil counts (HCV positive, 9% vs. HCV negative, 3%, P <.0001) and 2.6-fold more likely to have low platelet counts (HCV positive, 13% vs. HCV negative, 5%, P <.0001) independent of other evaluated factors. HCV infection was observed in more than 20% of persons with neutrophil counts below 1.0 x 10(9)/L or platelet counts less than 100 x 10(9)/L. No association was detected between anti-HCV status and anemia or other peripheral blood cell components. In conclusion, HCV-infected persons in the general population of the United States are more likely to have low neutrophil and platelet counts, and HCV testing should be considered for persons with unexplained neutrophil counts below 1.0 x 10(9)/L or platelet counts less than 100 x 10(9)/L. Alternate causes of anemia should be considered for HCV-infected persons with low red blood cell counts.

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.

Viral infections and antiphospholipid antibodies

OBJECTIVE

To study the relationship between viral infections and the induction of antiphospholipid (aPL) antibodies.

METHODS

We reviewed the medical literature from 1968 until 2000 using MEDLINE and the key words virus, infection, antiphospholipid, and anticardiolipin.

RESULTS

Anticardiolipin antibodies and/or lupus anticoagulant were associated with a number of viral infections, including hepatitis C virus, human immunodeficiency virus, cytomegalovirus, varicella zoster, Epstein-Barr virus, adenovirus, and parvovirus B. In many instances, the presence of these antibodies was associated with thrombosis.

CONCLUSION

The clinical significance of finding aPL antibodies in patients with viral infections remains unknown. In some patients, these antibodies may be transient and disappear within 2 or 3 months. In other susceptible individuals, they may persist and raise the question of whether infections may trigger the development of aPL antibodies in autoimmune diseases.

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.

Immunopathogenesis of vasculitis

Vasculitis is defined by the presence of leukocytes in the vessel wall with reactive damage to mural structures, leading to tissue ischemia and necrosis. The immunopathologic events that initiate the process of vascular inflammation and blood vessel damage are unclear. Damage of vascular endothelial cells and the recruitment and accumulation of the inflammatory infiltrate are determined by the endothelial cell and the bystanders, including the expression of adhesion molecules, the secretion of peptides and hormones, and the specific interaction with inflammatory cells. In addition to the endothelial cells, which provide costimulatory function, other cellular components and nonendothelial structures of the vessel wall are involved in controlling the inflammatory process, serve as antigen-presenting cells, and contribute with inflammatory mediators.

Whole stimulated salivary flow in patients with chronic hepatitis C virus infection

BACKGROUND

Salivary gland disorders have been included among the extra-hepatic manifestations related to HCV infection.

METHODS

The whole stimulated salivary flow rate (spitting technique) was studied in 74 HCV infected patients to evaluate salivary gland dysfunction.

RESULTS

The salivary flow of the patients with chronic HCV infection was similar to that of the healthy controls. The association between subjective xerostomia salivary flow was seen to be very weak. No significant associations were found between salivary flow and age, sex, risk factor of acquired infection, ALT, AST, GGT, ALP values, time lapsed since the diagnosis or HCV-RNA detection in saliva.

CONCLUSIONS

Although the functional repercussion of hepatitis C related lymphocytic sialoadenitis remains unclear, we did not find a significant reduction in the whole stimulated salivary flow in HCV infected patients.

Increased incidence of anti-LKM autoantibodies in a consecutive cohort of hepatitis C patients from central Greece

OBJECTIVES

In Greece, there are insufficient data regarding the presence of non-organ and liver-related autoantibodies in hepatitis C patients. This study in a consecutive cohort of 39 such patients from central Greece investigates (1) the prevalence of non-organ and liver-related autoantibodies, and (2) the reactivity of anti-liver-kidney microsomal type 1 antibodies (in the case of positivity with at least one of the methods used) against their molecularly defined antigens.

DESIGN

All serum samples were tested by standard and molecular assays for the presence of anti-nuclear antibodies, smooth muscle antibodies, anti-liver-kidney microsomal type 1 antibodies, antibodies against parietal cells, anti-CYP2A6, anti-CYP1A2 and anti-CYP2D6 autoantibodies.

METHODS

Indirect immunofluorescence, competitive enzyme-linked immunosorbent assays, immunoblotting and novel radioligand assays based on immunoprecipitation of [35S]-methionine labelled recombinant CYP2A6, CYP1A2 and CYP2D6 His-taq fusion proteins produced by in vitro transcription/translation were used.

RESULTS

Seven out of 39 patients (17.9%) tested positive for smooth muscle antibodies, 2/39 (5.1%) tested positive for anti-nuclear antibodies, 1/39 (2.5%) tested positive for parietal cell antibodies, and 4/39 (10.3%) were found to be anti-liver-kidney microsomal positive (with at least one of the methods used). All sera were negative for anti-CYP2A6 and anti-CYP1A2 autoantibodies. Three out of four anti-liver-kidney microsomal positive samples had the typical liver-kidney microsomal staining pattern shown by indirect immunofluorescence. However, none tested positive for anti-CYP2D6 autoantibodies using the competitive CYP2D6 enzyme-linked immunosorbent assay, the specific CYP2D6 radioligand assay, and western blot using either human microsomes or recombinant CYP2D6. The fourth patient tested negative for anti-liver-kidney autoantibodies by either indirect immunofluorescence or the competitive enzyme-linked immunosorbent assay, but was repeatedly positive for anti-CYP2D6 autoantibodies by the sensitive and specific radioligand assay. Western blot experiments using human microsomes in this patient serum revealed two bands of 50 kDa and 55 kDa that documented as anti-CYP2D6 and anti-uridine triphosphate glucuronosyltransferase autoantibodies when recombinant CYP2D6 and recombinant uridine triphosphate glucuronosyltransferase autoantigens were used for immunoblot, respectively.

CONCLUSIONS

A relatively high incidence of anti-liver-kidney microsomal autoantibodies (10.3%) was found in a consecutive sample of Greek patients with hepatitis C. The expanded panel of assays, however, failed to document CYP2D6 as the target autoantigen of anti-liver-kidney microsomal autoantibodies in most patients. We report for the first time the detection of parietal cell antibodies and both anti-CYP2D6 (anti-liver-kidney microsomal type 1) and anti-uridine triphosphate glucuronosyltransferase (anti-liver-kidney microsomal type 3) autoantibodies in patients who were hepatitis C positive/hepatitis D negative. Further studies are needed to confirm our findings and to determine whether these preliminary results have a clinical importance or not.

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.

Cryoglobulinemic glomerulonephritis in thymic stromal lymphopoietin transgenic mice

Mixed cryoglobulins are complexes of immunoglobulins that reversibly precipitate in the cold and lead to a systemic disease in humans. Renal involvement usually manifests as a membranoproliferative glomerulonephritis with marked monocyte infiltration and, at times, intracapillary thrombi. Thymic stromal lymphopoietin (TSLP) is a recently cloned cytokine that supports differentiation and long-term growth of B cells. Here we report that TSLP overexpression in mice results in the development of mixed cryoglobulins, with renal involvement closely resembling cryoglobulinemic glomerulonephritis as it occurs in humans. One hundred twenty-three mice were sacrificed at monthly intervals, with at least five TSLP transgenic mice and five controls in each group. Blood, kidneys, spleen, liver, lung, and ear were collected and studied by routine microscopy, immunofluorescence, immunohistochemistry, and electron microscopy. TSLP transgenic animals developed polyclonal mixed cryoglobulinemia (type III) and a systemic inflammatory disease involving the kidney, spleen, liver, lung, and ears. Renal involvement was of a membranoproliferative type demonstrating thickened capillary walls with cellular interposition and double contours of the basement membrane, expansion of the mesangium because of increased matrix and accumulation of immune-deposits, subendothelial immune-deposits, focal occlusion of capillary loops, and monocyte/macrophage influx. In contrast to the severe glomerular lesions, the tubulointerstitium was not involved in the disease process. The renal lesions and the disease course were more severe in females when compared to males. We describe a mouse strain in which a B-cell-promoting cytokine leads to formation of large amounts of mixed cryoglobulins and a systemic inflammatory injury that resembles important aspects of human cryoglobulinemia. This is the first reproducible mouse model of renal involvement in mixed cryoglobulinemia, which enables detailed studies of a membranoproliferative pattern of glomerular injury.

Vasculitic neuropathies

Vasculitis typically affects the 50- to 400-micron vessels of the vasa nervorum, leading to randomly distributed ischemia along the course of the nerve. This, in turn, leads to a distinctive picture, multiple mononeuropathy, as a frequent but not invariant clinical consequence of vasculitis. The diagnosis of vasculitic neuropathy is usually made by biopsy histologic confirmation. The response to treatment varies among different vasculitides; vasculitis restricted to the peripheral nervous system is often especially responsive.

[Peripheral neuropathy and hepatitis C virus infection: more than cryoglobulinemia]

PURPOSE

To study characteristics of peripheral neuropathies associated with hepatitis C virus infection.

METHODS

A study of two groups of four patients with peripheral neuropathy and infected with hepatitis C virus, and a literature review.

RESULTS

We observed four cases of peripheral neuropathy in patients with hepatitis C virus infection with persistent negativity of mixed cryoglobulinemia, and with no purpura, rheumatoid factor, or low C4 level. Neuropathy improved with treatment in three patients between 8 and 28 months after treatment was begun. We report four other observations of peripheral neuropathy with mixed cryoglobulinemia. Worsening of peripheral neuropathy was observed 2 to 13 weeks after initiation of interferon alpha despite improvement of hepatic parameters. After stopping interferon, peripheral neuropathy worsened (one case), stabilized (one case), or improved (two cases).

DISCUSSION

In patients infected with hepatitis C virus, peripheral neuropathy can be due to mixed cryoglobulinemia, periarteritis nodosa, and perhaps hepatitis C virus itself as suggested by our first observations. Low doses of interferon alpha may worsen peripheral neuropathy in patients with mixed cryoglobulinemia, as suggested in our later observations.

Influence of HLA-DR phenotype on the risk of hepatitis C virus-associated mixed cryoglobulinemia

OBJECTIVE

Circumstances predisposing hepatitis C virus (HCV)-infected patients to develop mixed cryoglobulinemia (MC), which may manifest as a small-vessel systemic vasculitis (MC vasculitis), remain unclear. Previous studies have failed to demonstrate a clear role of either viral factors (genotype, viral load) or host factors (lymphocytes or immunoglobulin subsets). This study was undertaken to examine a possible role of HLA class II alleles in HCV-associated MC.

METHODS

One hundred fifty-eight HCV-infected patients, of whom 76 had MC (56 with type II MC and 20 with type III MC) and 82 did not have MC, were studied prospectively. MC vasculitis was noted in 35 HCV-infected patients with type II IgMkappa-containing cryoglobulins. HLA-DRB1 and HLA-DQB1 polymorphism was analyzed by hybridization using allele-specific oligonucleotides, after gene amplification. The odds ratio (OR) was calculated with Woolf's method. Then, using multivariate analysis, demographic, biologic, immunologic, virologic, and liver histologic factors associated with the presence of MC and MC vasculitis were investigated.

RESULTS

HLA-DR11 was significantly more frequent in patients with type II MC than in those without MC (41.1% versus 17.1%; OR 3.4, corrected P [Pcorr] = 0.017), regardless of the presence of vasculitis accompanying the MC (37.1% of those with MC vasculitis, 34.1% of those with MC but no vasculitis). HLA-DR7 was less frequent in HCV-infected patients with MC than in those without MC (13.2% versus 30.5%; OR 0.34, P = 0.012, Pcorr not significant), with a particularly lower frequency in those with type II MC and those with MC vasculitis (12.5% and 8.6%, respectively). There was no significant difference in HLA-DQB1 distribution between the different patient groups. By univariate and multivariate analysis, HLA-DR11 was the only positive predictive factor, besides female sex and advanced age, for the presence of MC and HCV-associated MC vasculitis (OR 2.58).

CONCLUSION

Our results indicate that the presence of the DR11 phenotype is associated with a significantly increased risk for the development of type II MC in patients with chronic HCV infection. In contrast, HLA-DR7 appears to protect against the production of type II MC. These results suggest that the host's immune response genes may play a role in the pathogenesis of HCV-associated MC.