Hepatitis C virus infection and vasculitis: implications of antiviral and immunosuppressive therapies

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.

Central nervous system vasculitis in children

PURPOSE OF THE REVIEW

To summarize the current literature on central nervous system vasculitis in childhood because this condition remains a diagnostic and therapeutic challenge.

RECENT FINDINGS

Central nervous system vasculitis in childhood may be primary or secondary to a variety of conditions including infections, collagen vascular diseases, systemic vasculitides, and malignancies. Conditions that result in vasospasm or are associated with noninflammatory vasculopathies may mimic the features of central nervous system vasculitis. Recent studies have described the clinical spectrum of CNS vasculitis in childhood. The most common presenting features are headaches and focal neurologic deficits. The diagnosis of central nervous system vasculitis remains particularly difficult because the available investigative modalities have limited sensitivities and specificities. The most helpful diagnostic tests include cerebrospinal fluid analysis, MRI of the brain, and angiography. However, brain biopsy may be required to diagnose small vessel vasculitis.

SUMMARY

This review summarizes recent data on primary central nervous system vasculitis and some of the secondary CNS vasculitides in children. Awareness of the presenting clinical features of CNS vasculitis should lead to consideration of the diagnosis. Awareness of the sensitivity and specificity of the various diagnostic tests should lead to the more prudent use of invasive diagnostic tests including angiography and brain biopsy.

The peripheral nerve complications of human immunodeficiency virus (HIV) infection

Peripheral nerve complications occurring in patients with human immunodeficiency virus (HIV) infection are frequent and challenging. This review discusses these various complications according to the degree of advancement of HIV disease. Particular emphasis is placed upon emerging causes of neuropathy found in the context of HIV disease, such as infection with hepatitis C and human T-lymphotropic virus type I, as well as neuropathies related to antiretroviral medications.

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.

Hepatitis C virus-related cryoglobulinemic glomerulonephritis: long-term remission after antiviral therapy

BACKGROUND

Renal involvement in patients with hepatitis C virus (HCV) infection commonly manifests as cryoglobulinemic glomerulonephritis (CGN). The combination of interferon-alpha (IFN-alpha) and ribavirin, which is currently considered the standard antiviral therapy in chronic hepatitis C, could be difficult to carry out in cryoglobulinemic patients who are frequently anemic, even in the absence of renal failure. Clinical and histologic long-term results of this therapeutic regimen have not been so far reported in patients with CGN.

METHODS

Three patients with HCV-related CGN and slightly impaired kidney function were treated with IFN-alpha and ribavirin for 12 months, and subsequently were followed up for 24 to 36 months. Two of these patients who were anemic were pretreated with erythropoietin (EPO). In each patient renal biopsy was performed before starting therapy and repeated 14 to 26 months after the end of treatment.

RESULTS

In all three patients, antiviral therapy induced sustained virologic response, which was followed by clear improvement in clinical, biochemical, immunologic, and histologic features. Clinical and biochemical improvement steadily progressed in all three patients, achieving normal or nearly normal results at the end of follow-up. In contrast, some immunologic features, such as serum levels of C4 and rheumatoid factor activity, did not normalize in two and three patients, respectively. Posttreatment renal biopsies showed mildly active histologic lesions.

CONCLUSION

Antiviral therapy with IFN-alpha and ribavirin may be considerably beneficial in patients with HCV-related CGN who obtain sustained virologic response.

Upcoming biologic agents for the treatment of rheumatic diseases

The development of biologic agents has provided rheumatologists with a variety of new and effective treatment options. The success of early biologics, especially etanercept and infliximab for the treatment of rheumatoid arthritis, has spurred research into novel targets for the management of systemic inflammatory and autoimmune diseases. In addition, existing biologics approved for use in other diseases, such as rituximab, are now under study for the treatment of new indications. This article reviews ongoing research on the treatment of rheumatic diseases with new and existing biologic agents.

Infectious etiology of vasculitis: diagnosis and management

Vasculitides are a heterogeneous group of syndromes characterized by inflammation of the vessel wall. Several microbial pathogens have been known or suspected to cause vasculitis, and the development of molecular biology has promoted the search and confirmation of infectious agents in idiopathic vasculitis. Though several agents present primarily as an infectious process with vasculitis as an occasional manifestation, vasculitis may be the major manifestation of disease. Less definitive, and more controversial, is the role of infection and inflammation of the vessel wall in the pathogenesis of atherosclerotic disease. Clinical features can be nonspecific, and a high index of suspicion is required in order to make a diagnosis of vasculitis. Infection should always be excluded based on appropriate cultures and serologic assays, and, if confirmed, early and aggressive treatment should be instituted. However, in many instances, especially if there is a delay in the diagnosis, surgical intervention becomes necessary to treat the associated anatomic and physiologic sequelae.

Hepatitis C virus and arthritis

Arthritis is one of the several autoimmune disorders induced by HCV infection. There is not a specific clinical pattern of HCV-related arthritis, but two nonerosive subsets have more frequently been described: a RA-like polyarthritis and a less common mono-oligoarthritis involving medium-sized and large joints, often showing an intermittent course. This latter form is associated with the presence of serum cryoglobulins. Because of its variable characteristics, HCV-related arthritis must be considered in the differential diagnosis of many patients having inflammatory joint involvement. Antikeratin antibodies and possibly IgA RF can be useful in distinguishing between RA and HCV-related RA-like polyarthritis. In fact, these tests are highly specific in RA patients. In any case, the search for HCV antibodies should be more widely performed in the diagnostic approach to rheumatic diseases. An association between PsA and HCV infection has been described in the literature, but the authors were unable to confirm these data. Nonsteroidal anti-inflammatory drugs, hydroxychloroquine, and low doses of corticosteroids are the cornerstones of the treatment of HCV-related arthritis. An etiologic therapy with alpha-interferon and ribavirin is useful when required by hepatic or systemic involvement; such therapy could also be considered in selected cases of isolated arthritis that are unresponsive to other drugs. Few case reports described the onset of polyarthritis after the administration of alpha-interferon for HCV-related chronic hepatitis. This topic should be more accurately studied in the future to exclude a spurious association between the two events.

15. Vasculitis

Vasculitis is histologically defined by the presence of blood vessel inflammation. It can be observed in a wide variety of settings, either occurring secondarily to another process or as the pathologic foundation of a primary vasculitic disease. The primary systemic vasculitides comprise a broad group of disease entities that are uniquely identified by the nature of their clinical, histopathologic, or therapeutic characteristics. Individual diseases often predominantly affect blood vessels of a particular size, the pattern of which influences their clinical manifestations and has been used in their classification. The vasculitides span a wide range of disease severity, extending from illnesses that rarely produce death to those almost universally fatal before the introduction of effective therapy. Immunosuppressive and cytotoxic agents are used to treat many vasculitic diseases. Although such approaches can be effective, long-term treatment may be complicated by chronic sequelae from organ damage, disease relapses, and medication side effects. Recent investigations have focused on understanding the pathophysiology of these diseases, which may lead to more efficacious and less toxic therapeutic options.

Biologic therapies in the vasculitides

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

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.