Rituximab in mixed cryoglobulinemia: increased experience and perspectives

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

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

The dilemma of treating hepatitis C virus-associated cryoglobulinemia

PURPOSE OF REVIEW

The present review focuses on the new therapeutic opportunities offered by the combination of biological drugs, mainly Rituximab, with direct-acting antiviral agents (DAAs).

RECENT FINDINGS

Hepatitis C virus (HCV) is known to be the etiologic agent in the majority of patients with mixed cryoglobulinemia syndrome. Clinical research has been focused on antiviral drugs and, more recently, on the new, highly potent DAAs. New DAAs assure sustained virologic response (SVR) rates greater than 90% with relief of mild-to-moderate symptoms.

SUMMARY

Mixed cryoglobulinemia may present with multiorgan vasculitis involving kidneys, joints, skin, and peripheral nerves. Data on DAAs efficacy in HCV-associated cryoglobulinemic vasculitis are disappointing possibly because of the inability of these drugs to suppress the immune-mediated process once it has been triggered. Immunosuppression has often been employed in the past as a first-line therapy in cryoglobulinemic vasculitis despite the potential risk of the infection exacerbation. However, more manageable Rituximab-based therapeutic approaches have been more recently used without increase of viral load. Rituximab substantially changed the outcome of HCV-associated cryoglobulinemic vasculitis by providing long-term remission. A combination schedule of DAAs and Rituximab may result in eradication of both cryoglobulinemic vasculitis and HCV infection.

Cryoglobulinaemia

Cryoglobulinaemia refers to the serum presence of cryoglobulins, which are defined as immunoglobulins that precipitate at temperatures <37 °C. Type I cryoglobulinaemia consists of only one isotype or subclass of monoclonal immunoglobulin, whereas type II and type III are classified as mixed cryoglobulinaemia because they include immunoglobulin G (IgG) and IgM. Many lymphoproliferative, infectious and autoimmune disorders have been associated with mixed cryoglobulinaemia; however, hepatitis C virus (HCV) is the aetiologic agent in most patients. The underlying mechanism of the disorder is B cell lymphoproliferation and autoantibody production. Mixed cryoglobulinaemia can cause systemic vasculitis, with manifestations ranging from purpura, arthralgia and weakness to more serious lesions with skin ulcers, neurological and renal involvement. This Primer focuses on mixed cryoglobulinaemia, which has a variable course and a prognosis that is primarily influenced by vasculitis-associated multiorgan damage. In addition, the underlying associated disease in itself may cause considerable mortality and morbidity. Treatment of cryoglobulinaemic vasculitis should be modulated according to the underlying associated disease and the severity of organ involvement and relies on antiviral treatment (for HCV infection), immunosuppression and immunotherapy, particularly anti-CD20 B cell depletion therapies.

The challenge of treating hepatitis C virus-associated cryoglobulinemic vasculitis in the era of anti-CD20 monoclonal antibodies and direct antiviral agents

Mixed cryoglobulinemia syndrome (MC) is a systemic vasculitis involving kidneys, joints, skin, and peripheral nerves. While many autoimmune, lymphoproliferative, and neoplastic disorders have been associated with this disorder, hepatitis C virus (HCV) is known to be the etiologic agent in the majority of patients. Therefore, clinical research has focused on anti-viral drugs and, more recently, on the new, highly potent Direct-acting Antiviral Agents (DAAs). These drugs assure sustained virologic response (SVR) rates >90%. Nevertheless, data on their efficacy in patients with HCV-associated cryoglobulinemic vasculitis are disappointing, possibly due to the inability of the drugs to suppress the immune-mediated process once it has been triggered.Despite the potential risk of exacerbation of the infection, immunosuppression has traditionally been regarded as the first-line intervention in cryoglobulinemic vasculitis, especially if renal involvement is severe. Biologic agents have raised hopes for more manageable therapeutic approaches, and Rituximab (RTX), an anti CD20 monoclonal antibody, is the most widely used biologic drug. It has proved to be safer than conventional immunosuppressants, thus substantially changing the natural history of HCV-associated cryoglobulinemic vasculitis by providing long-term remission, especially with intensive regimens.The present review focuses on the new therapeutic opportunities offered by the combination of biological drugs, mainly Rituximab, with DAAs.

Efficacy of low-dose rituximab for the treatment of mixed cryoglobulinemia vasculitis: Phase II clinical trial and systematic review

OBJECTIVE

To evaluate whether rituximab at a low dose of 250 mg/m(2) × 2 may be as effective as at higher dosages, most commonly 375 mg/m(2)×4, used in previous studies on the treatment of patients with refractory mixed cryoglobulinemia (MC) vasculitis associated with hepatitis C virus (HCV) infection.

METHODS

We conducted a phase 2, single-arm two-stage trial (EUDRACT n. 2008-000086-38) of low-dose rituximab in 52 patients with HCV-associated MC who were ineligible/intolerant or non-responder to antiviral therapy. The primary outcomes were response of vasculitis evaluated by the Birmingham Vasculitis Activity Score (BVAS) at months 3, 6 and 12, rate of relapses and time to relapse, and rate of adverse events. Our data were compared with those reported in 19 published studies selected among 291 reviewed in a literature search.

RESULTS

The cumulative response rate (complete and partial) at month 3 was 81% in our patients, and 86% in 208 patients from studies using high-dose rituximab. The relapse rate and median time to relapse were, respectively, 41% and 6 months in our study, and 32% and 7 months in high-dose studies. Treatment-related adverse events were 11.5% in our study and 19.9% in high-dose studies. None of these differences was statistically significant.

CONCLUSION

Rituximab at a low dosage of 250 mg/m(2) × 2 is as effective as at higher dosages for treating MC vasculitis. This low-dose regimen may improve the cost/benefit profile of rituximab therapy for MC.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Vasculitic neuropathies

The vasculitic neuropathies are a diverse group of disorders characterised by the acute-to-subacute onset of painful sensory and motor deficits that result from inflammatory destruction of nerve blood vessels and subsequent ischaemic injury. They are common in patients with primary systemic vasculitis and are seen in vasculitis secondary to disorders such as rheumatoid arthritis, viral infections, and diabetic inflammatory neuropathies. It is imperative that neurologists recognise these disorders to initiate treatment promptly and thereby prevent morbidity and mortality. To simplify the approach to patients with vasculitis of the peripheral nerves, a straightforward, dichotomous classification scheme can be used in which the vasculitic neuropathies are divided into two groups-nerve large arteriole vasculitis and nerve microvasculitis-on the basis of the size of the involved vessels. The size of the affected blood vessels correlates with the clinical course and prognosis in patients with vasculitic neuropathy.

The vasculitic neuropathies: an update

PURPOSE OF REVIEW

Vasculitic neuropathy is a heterogeneous disorder that usually occurs in systemic diseases, but less commonly appears as nonsystemic vasculitic neuropathy (NSVN). This review is intended to highlight recent developments in the field of vasculitic neuropathies.

RECENT FINDINGS

A Peripheral Nerve Society guideline provides data-driven consensus recommendation on classification of vasculitic neuropathies and diagnosis/treatment of NSVN. NSVN is sometimes accompanied by subclinical inflammation of adjacent skin. Amyotrophic lateral sclerosis with sensory involvement can mimic NSVN. Systemic vasculitides with neuropathy include polyarteritis nodosa, microscopic polyangiitis (MPA), rheumatoid vasculitis, Churg-Strauss syndrome (CSS), and hepatitis C-related mixed cryoglobulinemic vasculitis (MCV). At autopsy, MPA affects limb nerves diffusely, with maximal damage in proximal/middle segments. CSS can be accompanied by antineutrophil cytoplasmic antibodies (ANCAs), but most patients with neuropathy lack ANCAs. Cryoglobulinemic neuropathies are usually caused by vasculitis, irrespective of phenotype. Two randomized trials revealed rituximab to be noninferior to cyclophosphamide for inducing remission in ANCA-associated vasculitis. Many reports also document efficacy of rituximab in MCV.

SUMMARY

Consensus guidelines on NSVN should be evaluated prospectively. MPA-associated vasculitic neuropathy results from vasculitic lesions distributed diffusely throughout peripheral extremity nerves. Rituximab is effective for ANCA-associated and cryoglobulinemic vasculitis with neuropathy.

Hepatitis C virus infection, mixed cryoglobulinemia, and kidney disease

Hepatitis C virus (HCV) may instigate mixed cryoglobulinemia; the most significant accompanying kidney lesion is type I membranoproliferative glomerulonephritis, usually occurring in the context of type II mixed cryoglobulinemia. Additionally, recent data support a link between HCV infection and proteinuria in population-based studies, raising the possibility that kidney diseases associated with HCV may be more common than previously thought. A number of strategies have been used to treat HCV-related glomerulonephritis, including antiviral agents, immunosuppressive therapies such as corticosteroids and cytotoxic agents, and plasma exchange. Limited but encouraging data about the utility of antiviral treatment in the setting of HCV-associated glomerulonephritis exist, with one pooled analysis noting a sustained viral response of 42%, albeit with significant heterogeneity. Immunosuppressive therapy may be most useful for cryoglobulinemic kidney disease, with individualized approaches considered for the treatment of HCV-associated cryoglobulinemic glomerulonephritis based on the level of proteinuria and kidney failure. Of note, rituximab, a chimeric monoclonal antibody that blocks CD20 receptors on B cells, has been reported to be effective for the treatment of mixed cryoglobulinemia symptoms, including glomerulonephritis.

Treatment of rheumatoid arthritis in patients with concomitant chronic hepatitis C infection

Hepatitis C virus (HCV) infection is present in 1.8% of the general US population and its prevalence worldwide is estimated at 2-3%. HCV infected patients with concomitant rheumatoid arthritis (RA) pose a particular challenge to the rheumatologist because of the risks of treatment with disease-modifying medications in patients with chronic liver infection. In this paper the difficulties of diagnosing RA in HCV patients and the safety of RA treatment in patients with both conditions are discussed.

Hepatitis C virus, cryoglobulinemia, and kidney: novel evidence

Hepatitis C virus infection can lead to chronic active hepatitis, cirrhosis, and liver failure; however, it is also associated with a wide range of extra-hepatic complications. HCV is associated with a large spectrum of histopathological lesions in both native and transplanted kidneys, and it is increasingly recognized as an instigator of B cell lympho-proliferative disorders including mixed cryoglobulinemia. Mixed cyoglobulinemia is a systemic vasculitis primarily mediated by immune complexes; it is characterized by variable organ involvement including skin lesions, chronic hepatitis, glomerulonephritis, peripheral neuropathy, and arthralgias. The most frequent HCV-associated nephropathy is type I membranoproliferative glomerulonephritis, usually in the context of type II mixed cryoglobulinemia. Various approaches have been tried for the treatment of HCV-related glomerulonephritis, including immunosuppressive therapy (corticosteroids and cytotoxic agents), plasma exchange and antiviral agents. Data on the antiviral treatment of HCV-associated glomerulonephritis are not abundant but encouraging results have been provided. Immunosuppressive therapy is particularly recommended for cryoglobulinemic kidney disease. Recent evidence has been accumulated on rituximab therapy for HCV-related cryoglobulinemic glomerulonephritis exists but several questions related to its use remain unclear. Distinct approaches should be considered for the treatment of HCV-associated cryoglobulinemic glomerulonephritis according to the level of proteinuria and kidney failure.

Safety and efficacy of rituximab treatment for vasculitis in hepatitis B virus-associated type II cryoglobulinemia: a case report

Introduction

Systemic B-cell depletion and clinical remission of the systemic effects of cryoglobulins have already been achieved using rituximab in hepatitis C virus-positive immunocompetent patients. Conversely, to the best of our knowledge there are no reports in the literature regarding the use of rituximab in hepatitis B virus-associated cryoglobulinemia.

Case presentation

We report here the case of a 60-year-old Caucasian man who presented with hepatitis B virus-associated type II cryoglobulinemia with severe multisystem disease, including membranoproliferative glomerulonephritis with acute renal failure. The vasculitis was refractory to conventional and antiviral therapy but rituximab use led to a fall in cryoglobulin levels and disease control. The B-cell depletion was safe and efficient to induce a complete remission of the disease.

Conclusion

Our case highlights the benefit and the efficacy of rituximab in association with antiviral therapy in small vessel vasculitis related to hepatitis B virus-associated mixed cryoglobulinemia.

Treatment with rituximab in patients with mixed cryoglobulinemia syndrome: results of multicenter cohort study and review of the literature

OBJECTIVE

Mixed cryoglobulinemia syndrome (MCs) is a systemic vasculitis characterized by multiple organ involvement due to the vascular deposition of immune-complexes, mainly the cryoglobulins. B-lymphocyte expansion represents the underlying pathological alteration frequently triggered by hepatitis C virus (HCV) infection. The treatment of MCs syndrome is generally based on antiviral drugs and/or immunosuppressors, among which rituximab, an anti-CD20 monoclonal antibody, has been usefully employed for both cutaneous and visceral MCs organ involvement. This multicenter study retrospectively evaluated the effects of rituximab in a large series of patients with active MCs. The observed results were compared to those emerging from the updated review of the literature on this topic.

METHODS

The study included 87 patients (male/female 19/68, mean age 62.3±11.4SD years, mean disease duration 9±6.2SD years, HCV infection in 92% of cases) with active cryoglobulinemic vasculitis evaluated before rituximab monotherapy and after 6-month follow-up by means of main clinico-serological parameters. A PubMed search up to May 31, 2011, was done to find published clinical studies, including case reports of MCs treated with rituximab.

RESULTS

A significant clinical improvement was observed in a relevant percentage of cases, regardless the presence/absence of associated HCV infection; namely, complete/partial remission of pre-treatment active manifestations was observed in 74% of skin purpuric lesions, up to 87% of non-healing vasculitic leg ulcers, and 44% of the peripheral neuropathy, mainly paresthesias (patient's visual analogical scale from 62±25 to 37±27; p≤.0001). Moreover, cryoglobulinemic nephropathy, observed in 38 patients, significantly improved in 95% of cases (serum creatinine from 1.8±1.1SD to 1.4±0.8SD mg/dl, p≤.0001; 24-hour proteinuria from 2.2±2.1SD to 0.9±1.7SD g/24h, p≤.0001), with complete remission in the 50%. Among 6 patients with complicating non-Hodgkin's B-cell lymphoma a complete or partial remission was observed in 5/6. A complete remission of abdominal vasculitis was also observed in one patient. These beneficial effects were mirrored by the improvement of cryoglobulinemic serological hallmarks, namely cryocrit and low complement C4, in half cases. The safety of rituximab was confirmed by the small number of side effects recorded during the 6-month follow-up. On the whole, the results of the present study are in keeping with those reported in 39 papers present in world literature, including a total of 279 MCs patients.

CONCLUSIONS

Rituximab may be regarded as useful and safe pathogenetic treatment of cryoglobulinemic vasculitis. The actual role of this drug should be definitely confirmed by randomized controlled trials, as well as its position in the therapeutical strategy, mainly with respect to antiviral treatment in HCV-associated MCs.

Anti-glutamic Acid decarboxylase antibody-associated ataxia as an extrahepatic autoimmune manifestation of hepatitis C infection: a case report

Extrahepatic immunological manifestations of hepatitis C virus (HCV) are well described. In addition, antiglutamic acid decarboxylase (GAD) antibody-associated cerebellar ataxia is well-established entity. However, there have been no reports in the literature of anti-GAD antibody-associated ataxia as an extrahepatic manifestation of HCV infection. We report the case of a young woman with chronic hepatitis C virus and multiple extrahepatic autoimmune diseases including Sjögren syndrome and pernicious anemia who presented with subacute midline cerebellar syndrome and was found to have positive antiglutamic acid decarboxylase (GAD) antibody in the serum and cerebrospinal fluid. An extensive diagnostic workup to rule out neoplastic growths was negative, suggesting the diagnosis of nonparaneoplastic antiglutamic acid decarboxylase antibody-associated cerebellar ataxia as an additional extrahepatic manifestation of hepatitis C virus infection. The patient failed to respond to high-dose steroids and intravenous immunoglobulin. Treatment with the monoclonal antibody rituximab stabilized the disease. We postulate that anti-GAD associated ataxia could be an extrahepatic manifestation of HCV infection.

An approach to the patient with retiform purpura

Retiform purpura consists of branching purpuric lesions caused by a complete blockage of blood flow in the dermal and subcutaneous vasculature. The differential diagnosis for retiform purpura is broad, including vasculitides of the small and medium vessels as well as microvascular occlusion due to thrombotic, infectious, and embolic phenomena. Determining the etiology of this important dermatologic sign can be a diagnostic challenge; however, an organized approach can improve the speed and accuracy of diagnosis and identify an effective treatment. This review focuses on early recognition, evaluation, and treatment of hospitalized patients with retiform purpura. Specifically, vasculitis, protein C and S deficiencies, heparin necrosis, warfarin necrosis, antiphospholipid antibody syndrome, disseminated intravascular coagulation, cryoglobulinemia, calciphylaxis, and cholesterol embolization syndrome will be discussed in detail. These conditions are commonly seen in consultative dermatology and can have multiorgan involvement, complicated laboratory evaluation, and long-term therapeutic implications.

Leukocytoclastic Vasculitis in a Patient with Type 1 Cryoglobulinemia

Cutaneous manifestations of type 1 cryoglobulinemia are usually related to vascular occlusion by noninflammatory thrombosis; rarely is leukocytoclastic vasculitis seen in type 1 cryoglobulinemia. We report the case of a 64-year-old male who presented with isolated cutaneous leukocytoclastic vasculitis that was initially attributed to essential mixed cryoglobulinemia after thorough diagnostic evaluation. A lack of adequate clinical response to therapy prompted further investigation, including cryoprecipitate electrophoresis and immunofixation, which revealed an IgM kappa monoclonal gammopathy consistent with type 1 cryoglobulinemia. A renewed search for an underlying malignancy led to the discovery of early Waldenstrom's macroglobulinemia. Although leukocytoclastic vasculitis is more characteristic of mixed cryoglobulinemia, it can be a presenting manifestation of type 1 cryoglobulinemia.

Serum levels of anti-CCP antibodies, anti-MCV antibodies and RF IgA in the follow-up of patients with rheumatoid arthritis treated with rituximab

Rheumatoid arthritis (RA) is characterized by the presence of circulating rheumatoid factor (RF) and anticitrullinated peptide antibodies (ACPA), which are positive in about 70-80% of patients. APCA have a higher specificity and therefore a higher diagnostic power than RF, but are less informative than RF in monitoring the course of the disease in patients under treatment. Recently, it has been reported that the anticitrullinated vimentin (a-MCV) antibody test can identify a particular subgroup of APCA that may be negative for anticyclic citrullinated peptide (a-CCP) antibodies. Concerning RF, the RF IgA isotype has been described as a more specific marker of erosive joint damage than total RF. The aim of our study was to monitor the levels of a-CCP, a-MCV, total RF and RF IgA in the follow-up of patients with RA treated with B-lymphocytedepletive rituximab (RTX), to detect any differences or peculiarities in patterns of these autoantibodies, especially in relation to their potential use as predictive markers of therapeutic response. We studied 30 patients with RA treated with RTX. All patients were previously unresponsive to at least 6 months of therapy with disease-modifying antirheumatic drugs (DMARDs; methotrexate, leflunomide, cyclosporine, chloroquine) and/or at least 6 months of therapy with anti-TNF biologics. The evaluation of response to RTX was made at month +6 using the EULAR criteria (DAS28). a-CCP, a-MCV, total RF and RF IgA were determined at baseline (before the first infusion of RTX) and after 1, 3 and 6 months. In serum samples obtained before treatment two cytokines essential for Blymphocyte proliferation, interleukin 6 (IL-6) and B-lymphocyte stimulator (BLyS) were also determined. In all patients a significant and consistent reduction in all the tested antibodies was found during follow-up, with no differences in respect of the degree of response to RTX. Of note, at baseline, generally a higher titre of all autoantibodies was seen in patients who then showed a better response to RTX. Finally, there were no differences in serum concentrations of IL-6 and BLyS in patients in relation to the presence or absence of the autoantibodies investigated, nor was there any significant correlation between the serum concentrations of the cytokines and the titres of the autoantibodies. Thus, neither a-MCV compared to a- CCP, nor RF IgA compared to routine total RF, provided any additional predictive information in the follow-up of patients with RA treated with RTX.

The A, B, Cs of viral hepatitis in the biologic era

PURPOSE OF REVIEW

To evaluate the recent published data on the safety of biological agents, mainly anti-TNFalpha and rituximab, and diagnostic difficulties in the setting of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and inflammatory arthritides.

RECENT FINDINGS

There are important differences between HBV and HCV carriers; however, clinical observations suggest that hepatotropic virus infection should not preclude the treatment with biologic agents in rheumatic diseases. Retrospective reports on limited series of HBV-infected patients with concomitant chronic arthritis convey that careful patients' clinico-virological assessment, in collaboration with the hepatologist, is necessary before starting immunosuppressive treatments, especially biological agents. Preemptive or combined antiviral treatment is mandatory, mainly in active and inactive HBV carriers. Occult HBV infection should be also carefully evaluated due to potential virus reactivation. In HCV-infected patients without chronic active hepatitis the treatment with biological agents, anti-TNFalpha or rituximab, is generally useful and well tolerated. Preliminary data suggest the possible synergic effects of combined antivirals (alpha-interferon and ribavirin) and anti-TNFalpha (or rituximab) in patients with chronic arthritis and active hepatitis C.

SUMMARY

In all patients with chronic arthritis requiring immunomodulating treatments both HBV and HCV infection along with liver conditions should be evaluated before any therapeutic decisions, including differential diagnosis among virus-related autoimmune disease and simple comorbidity. Patients with HBV infection should be referred to the hepatologist and correctly classified into active, inactive, and occult carriers. Similarly, rheumatic patients with active chronic hepatitis C must be treated with sequential or combined treatment with antiviral and biological agents.

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.

Hepatitis C-associated rheumatic disorders

Hepatitis C virus (HCV) is an important causative agent of liver diseases. However, HCV infection is also associated with numerous hematologic, renal, dermatologic, rheumatic, and autoimmune disorders. These include arthralgia, arthritis, vasculitis, sicca syndrome, myalgia, and fibromyalgia. The purpose of this article is to review the prevalence and spectrum of rheumatic disorders and autoimmune phenomena in HCV-infected patients. It evaluates and current treatment options including nonsteroidal anti-inflammatory drugs, low-dose corticosteroids, hydroxychloroquine, methotrexate, penicillamine, combined antiviral therapy, cyclosporin A, anti-TNF-a agents, and rituximab. It concludes that larger, controlled studies are needed to establish further the treatment indications, efficacy, and safety of these agents.