Extrahepatic manifestations of hepatitis C infection

Hepatitis C Virus-associated Cryoglobulinemic Livedo Reticularis Improved with Direct-acting Antivirals

We herein report a case of hepatitis C virus (HCV)-associated cryoglobulinemic livedo reticularis in a woman in her 60s that improved with direct-acting antivirals (DAAs). Hyperpigmentation was observed in both lower legs, and a skin biopsy confirmed livedo reticularis, suggesting a relationship with cryoglobulinemia and HCV infection. DAAs with an NS5A inhibitor+NS3/4A protease inhibitor (glecaprevir/pibrentasvir) were administered for eight weeks, and a sustained virological response (SVR) was obtained. The disappearance of serum cryoglobulin was confirmed approximately two years after an SVR was obtained and livedo reticularis was improved. DAA therapy can be an effective therapeutic option for extrahepatic complications associated with HCV infection.

Immunoassay Detects Salivary Anti-SSA/Ro-52 Autoantibodies in Seronegative Patients with Primary Sjögren's Syndrome

The diagnostic work-up for Sjögren's syndrome is challenging and complex, including testing for serum autoantibodies to SSA/Ro and a labial salivary gland biopsy. Furthermore, the diagnosis is often delayed. In this study, we tested the hypothesis that anti-SSA/Ro autoantibodies are detectable in the saliva of patients with primary Sjögren's syndrome (pSS) because the disease affects the salivary glands, and these autoantibodies display greater discriminatory performance in saliva than in serum. SSA/Ro-52 Ags were used to develop what is, to our knowledge, a novel quantitative electrochemical-based immunoassay: the electric field-induced release and measurement (EFIRM) platform. The clinical utility was determined by measuring salivary anti-SSA/Ro-52 autoantibodies in patients with pSS and sicca (n = 34), patients without pSS with sicca (n = 35), and healthy subjects (n = 41). The statistical analysis of discrimination included the area under the receiver operating characteristic curve. Salivary anti-SSA/Ro-52 autoantibodies were measured in 94% (32 of 34) of patients with pSS with 85% (29 of 34) seropositivity. Four of the five seronegative patients with pSS had EFIRM-measurable anti-SSA/Ro-52 autoantibodies in saliva. Additionally, 60% (21 of 35) of the seronegative patients without pSS who had sicca had EFIRM-detectable SSA/Ro-52 autoantibodies in saliva, indicating the onset of autoimmune disease. Two of the 41 healthy control subjects had EFIRM-detectable SSA/Ro-52 autoantibodies in their saliva. Salivary SSA/Ro-52 autoantibodies significantly discriminated patients with pSS or patients with the initial stage of autoimmune disease from healthy subjects with an area under the receiver operating characteristic curve of 0.91. Our findings suggest that the proposed saliva SSA/Ro-52 immunoassay improves early and accurate diagnosis of seronegative patients with pSS and patients with early-onset autoimmune disease.

Treating Hepatitis C Prior to Total Hip Arthroplasty is Cost Effective: A Markov Analysis

INTRODUCTION

Patients infected with the hepatitis C virus (HCV) have high complication rates following total hip arthroplasty (THA). Advances in HCV therapy now enable clinicians to eradicate the disease, however, its cost effectiveness from an orthopaedic perspective remains to be demonstrated. We sought to conduct a cost effectiveness analysis comparing no therapy to direct acting antiviral therapy (DAA) prior to THA among HCV positive patients.

METHODS

A Markov model was utilized to evaluate the cost-effectiveness of treating HCV with DAA prior to THA. The model was powered with event probabilities, mortality, cost and quality adjusted life-year values for patients with and without HCV that were obtained from the published literature. This included treatment costs, successes of HCV eradication, incidences of superficial or periprosthetic joint infection (PJI), probabilities of utilizing various PJI treatment modalities, PJI treatment success/failures, and mortality rates. The incremental cost-effectiveness ratio (ICER) was compared to a willingness-to-pay threshold of $50,000/QALY.

RESULTS

Our Markov model indicates that in comparison to no therapy, DAA prior to THA is cost-effective for HCV positive patients. THA in the setting of no therapy and DAA added 8.06 and 14.39 QALYs at a mean cost of $28,800 and $115,800. The ICER associated with HCV DAA in comparison to no therapy was $13,800/QALY, below the willingness-to-pay threshold of $50,000/QALY.

CONCLUSION

Hepatitis-C treatment with DAA prior to THA is cost-effective at all current drug list prices. Given these findings, strong consideration should be given to treating patients for HCV prior to elective THA.

Burden, Outcome, and Comorbidities of Extrahepatic Manifestations in Hepatitis C Virus Infection

Hepatitis C virus (HCV) is a significant cause of chronic liver diseases worldwide and is associated with negative consequences, including cirrhosis, hepatic decompensation, hepatocellular carcinoma, and increased risk of mortality. In addition to liver-related morbidities, HCV is also associated with several extrahepatic manifestations, including mixed cryoglobulinemia, diabetes mellitus, cardiocerebrovascular disease, lymphoma, and autoimmune diseases. These non-liver-related complications of HCV increase the complexity of this disease and can contribute to the economic burden, morbidity, quality of life, and mortality throughout the world. Therefore, understanding how this virus can contribute to each extrahepatic manifestation is worth investigating. Currently, the advancement of HCV treatment with the advent of direct-acting anti-viral agents (DAAs) has led to a high cure rate as a result of sustained virologic response and tremendously reduced the burden of extrahepatic complications. However, HCV-associated extrahepatic manifestations remain a relevant concern, and this review aims to give an updated highlight of the prevalence, risk factors, associated burdens, and treatment options for these conditions.

Viral infections in orthopedics: A systematic review and classification proposal

BACKGROUND

Although the impact of microbial infections on orthopedic clinical outcomes is well recognized, the influence of viral infections on the musculoskeletal system might have been underestimated.

AIM

To systematically review the available evidence on risk factors and musculoskeletal manifestations following viral infections and to propose a pertinent classification scheme.

METHODS

We searched MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), the Reference Citation Analysis (RCA), and Scopus for completed studies published before January 30, 2021, to evaluate risk factors and bone and joint manifestations of viral infection in animal models and patient registries. Quality assessment was performed using SYRCLE's risk of bias tool for animal studies, Moga score for case series, Wylde score for registry studies, and Newcastle-Ottawa Scale for case-control studies.

RESULTS

Six human and four animal studies were eligible for inclusion in the qualitative synthesis. Hepatitis C virus was implicated in several peri- and post-operative complications in patients without cirrhosis after major orthopedic surgery. Herpes virus may affect the integrity of lumbar discs, whereas Ross River and Chikungunya viruses provoke viral arthritis and bone loss.

CONCLUSION

Evidence of moderate strength suggested that viruses can cause moderate to severe arthritis and osteitis. Risk factors such as pre-existing rheumatologic disease contributed to higher disease severity and duration of symptoms. Therefore, based on our literature search, the proposed clinical and pathogenetic classification scheme is as follows: (1) Viral infections of bone or joint; (2) Active bone and joint inflammatory diseases secondary to viral infections in other organs or tissues; and (3) Viral infection as a risk factor for post-surgical bacterial infection.

MicroRNA-122 Regulation of HCV Infections: Insights from Studies of miR-122-Independent Replication

Despite the advancement in antiviral therapy, Hepatitis C remains a global health challenge and one of the leading causes of hepatitis related deaths worldwide. Hepatitis C virus, the causative agent, is a positive strand RNA virus that requires a liver specific microRNA called miR-122 for its replication. Unconventional to the canonical role of miRNAs in translation suppression by binding to 3′Untranslated Region (UTR) of messenger RNAs, miR-122 binds to two sites on the 5′UTR of viral genome and promotes viral propagation. In this review, we describe the unique relationship between the liver specific microRNA and HCV, the current knowledge on the mechanisms by which the virus uses miR-122 to promote the virus life cycle, and how miR-122 impacts viral tropism and pathogenesis. We will also discuss the use of anti-miR-122 therapy and its impact on viral evolution of miR-122-independent replication. This review further provides insight into how viruses manipulate host factors at the initial stage of infection to establish a successful infection.

Perioperative Management of Hepatitis C in Patients Undergoing Total Joint Arthroplasty

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A small yet growing subset of total joint arthroplasty (TJA) candidates are diagnosed with the hepatitis C virus (HCV), which is a known risk factor for periprosthetic joint infections. Given the poor outcomes associated with TJA infection, we recommend that candidates with HCV receive treatment prior to elective TJA.

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Interferon and ribavirin have historically been the standard treatment regimen for the management of HCV; however, adverse events and an inconsistent viral response have limited the efficacy of these therapies. The advent of direct-acting antivirals has resolved many of the issues associated with interferon and ribavirin regimens.

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Despite the success of direct-acting antivirals, there are still barriers to seeking treatment for TJA candidates with HCV. Many patients are faced with financial burdens, as insurance coverage of direct-acting antiviral therapies is inconsistent and varies by the patient's state of residence and specific treatment regimen.

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TJA candidates with HCV present health-care providers with a unique set of challenges, often encompassing economic, psychosocial, and complex medical concerns. Multidisciplinary care teams can be beneficial when caring for and optimizing this patient cohort.

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Management of HCV prior to elective TJA is associated with higher up-front costs but ultimately reduces long-term patient morbidity as well as associated direct and indirect health-care expenditures.

Antibody Responses in Hepatitis C Infection

Antibody responses in hepatitis C virus (HCV) have been a rather mysterious research topic for many investigators working in the field. Chronic HCV infection is often associated with dysregulation of immune functions particularly in B cells, leading to abnormal lymphoproliferation or the production of autoantibodies that exacerbate inflammation and extrahepatic diseases. When considering the antiviral function of antibody, it was difficult to endorse its role in HCV protection, whereas T-cell response has been shown unequivocally critical for natural recovery. Recent breakthroughs in the study of HCV and antigen-specific antibody responses provide important insights into viral vulnerability to antibodies and the immunogenetic and structural properties of the neutralizing antibodies. The new knowledge reinvigorates HCV vaccine research by illuminating a new path for the rational design of vaccine antigens to elicit broadly neutralizing antibodies for protection.

Impact of HCV eradication with direct-acting antiviral agents on serum gamma globulin levels in HCV and HCV/HIV coinfected patients

BACKGROUND

chronic viral infections by both HCV and HIV may lead to polyclonal activation of B cells resulting in hypergammaglobulinemia. This study retrospectively analyzed the effect of HCV eradication with interferon-free direct-acting antiviral agents (DAAs) on the gamma globulin levels in HCV-infected patients with or without HIV coinfection to identify factors potentially associated with gamma globulins decrease.

METHODS

The charts of patients treated with DAAs for HCV chronic infection between January 2015-June 2019 were retrospectively reviewed. Gamma globulin levels before treatment and 12 weeks after the end of anti-HCV therapy were evaluated along with liver tests, liver fibrosis stage by elastography, SVR achievement, HIV-coinfection. Multivariate analyses were carried out to assess the factors and the potential confounders related to the changes in gamma globulin levels.

RESULTS

A significant decrease of gamma globulin concentration was found in both cirrhotic and non-cirrhotic HCV-infected patients after treatment (from mean ± SD of 1.5 ± 0.44 g/dL to 1.31 ± 0.37 g/dL; p = 0.0001). Adjusted linear regression analyses of serum gamma globulin changes from baseline to SVR12 showed a positive significant association with pre-treatment gamma-globulin levels (β-coefficient -0.23; p = 0.0001), Metavir fibrosis score (β-coefficient -0.74; p = 0.008), ALT values and baseline HCV-RNA levels > 800,000. No difference was found between HIV-infected and HIV-uninfected patients.

CONCLUSIONS

Our study confirms previous preliminary observation of the decrease of serum gamma globulins after HCV eradication either achieved with interferon-based therapy or with DAAs, suggesting a leading role of the virus on the activation of B cell compartment and gamma globulins production.

Undetectable Hepatitis C Viral Load Is Associated With Improved Outcomes Following Total Joint Arthroplasty

BACKGROUND

Previous reports establish that infection with hepatitis C virus (HCV) predisposes total joint arthroplasty (TJA) recipients to poor postoperative outcomes. The purpose of the present study is to assess whether variation in HCV VL influences perioperative outcomes following TJA.

METHODS

A multicenter retrospective review of all patients diagnosed with HCV who underwent primary TJA between January 2005 and April 2018 was conducted. Patients were stratified into 2 cohorts: (1) patients with an undetectable VL (U-VL) and (2) patients with a detectable VL (D-VL). Kaplan-Meier survivorship analysis was calculated with revision TJA as the end point. Subanalysis on the VL profile was done.

RESULTS

A total of 289 TJAs were included (U-VL:118 TJAs; D-VL:171 TJAs). Patients in the D-VL cohort had longer operative times (133.9 vs 109.2 minutes), higher intraoperative blood loss (298.4 vs 219.5 mL), longer inpatient hospital stays (4.0 vs 2.9 days), more postoperative infections (11.7% vs 4.2%), and an increased risk for revision TJA (12.9% vs 5.1%). Kaplan-Meier demonstrated that the U-VL cohort trended toward better survivorship (P = .17). On subanalysis of low and high VL, no difference in outcomes was appreciated.

CONCLUSION

TJA recipients with a detectable HCV VL have longer operative times, experience more intraoperative blood loss, have longer hospital length of stay, and are more likely to experience infection and require revision TJA. The blood loss, hospital length of stay, and revision rate findings should be interpreted with caution, however, as there are confounding factors. Our findings suggest that HCV VL is a modifiable risk factor that, can reduce the risk of infection and revision surgery. Additionally, serum HCV VL was not correlated with outcomes.

APASL clinical practice recommendation: how to treat HCV-infected patients with renal impairment?

Chronic hepatitis C virus (HCV) infection is common among patients with chronic kidney disease (CKD) and those on hemodialysis due to nosocomial infections and past blood transfusions. While a majority of HCV-infected patients with end-stage renal disease are asymptomatic, some may ultimately experience decompensated liver diseases and hepatocellular carcinoma. Administration of a combination of elbasvir/grazoprevir for 12 weeks leads to high sustained virologic response (SVR) rates in patients with HCV genotypes (GTs) 1a, 1b or 4 and stage 4 or 5 CKD. Furthermore, a combination of glecaprevir/pibrentasvir for 8-16 weeks also results in high SVR rates in patients with all HCV GTs and stage 4 or 5 CKD. However, these regimens are contraindicated in the presence of advanced decompensated cirrhosis. Although sofosbuvir and/or ribavirin are not generally recommended for HCV-infected patients with severe renal impairment, sofosbuvir-based regimens may be appropriate for those with mild renal impairment. To eliminate HCV worldwide, HCV-infected patients with renal impairment should be treated with interferon-free therapies.

Hepatitis C virus infection and development of type 2 diabetes mellitus: Systematic review and meta-analysis of the literature

Type 2 diabetes mellitus (T2DM) is an endocrine disorder encompassing multifactorial mechanisms, and chronic hepatitis C virus infection (CHC) is a multifaceted disorder, associated with extrahepatic manifestations, including endocrinological disorders. CHC and T2DM are associated, but the subject remains controversial. We performed a systematic review and meta-analysis evaluating such association, searching on PubMed until February 29, 2016. Inclusion criteria were: 1) presence of at least one internal control group age- and gender-matched (non-hepatopathic controls; and/or hepatopathic, not HCV-positive, controls); 2) sufficient data to calculate odds ratio and relative risk. Exclusion criteria were: 1) literature reviews on the topic; 2) publications regarding special populations [human immunodeficiency virus and human T-lymphotropic virus-1 coinfections, hepatocellular carcinoma (HCC), post-transplantation DM, gender selection]; 3) no clear differentiation among HCV patients with CHC, cirrhosis or HCC. Data from each study were independently extracted by two reviewers and cross-checked by AA. Our systematic review returned 544 records, and 33 were included in our meta-analysis. HCV infection is associated with an increased risk of T2DM independently from the severity of the associated liver disease, in CHC and cirrhotic HCV patients. As expected T2DM risk is higher in cirrhotic HCV patients, than CHC, and the prevalence of HCV infection in T2DM patients is higher than in non-diabetic controls. Regarding HBV infection prevalence, no difference exists in diabetic and non-diabetic subjects. An unequivocal CHC and T2DM association was shown. A proactive, integrated approach to HCV and T2DM therapies should maximize benefits of both diseases treatment.

Hepatitis C is an Independent Risk Factor for Perioperative Complications and Nonroutine Discharge in Patients Treated Surgically for Hip Fractures

OBJECTIVE

To evaluate the relationship between noncirrhotic hepatitis C virus (HCV) infection, perioperative complications, and discharge status in patients undergoing surgical procedures for hip fractures.

METHODS

A retrospective epidemiological study was performed, querying the National Hospital Discharge Survey. Patients were selected using the International Classification of Diseases-9 diagnostic codes for hip fracture and primary procedural codes for open reduction internal fixation, hemiarthroplasty, total hip arthroplasty, or internal fixation. Patients with concurrent cirrhosis, HIV, hepatitis A, B, D, or E were excluded. Pearson χ tests, independent-samples t test, and multivariable binary logistic regression were used for data analysis.

RESULTS

Two cohorts surgically treated for a hip fracture were identified and compared. The first cohort included 5377 patients with a concurrent diagnosis of noncirrhotic HCV infection (HCV+) and the second included 4,712,159 patients without a diagnosis of HCV (HCV-). The HCV+ cohort was younger and had fewer medical comorbidities, yet was found to have a longer length of hospital stay, higher rates of nonroutine discharge, and higher rates of complications than the HCV- cohort. Multivariate regression analysis demonstrated that HCV+ is an independent risk factor for perioperative complications and nonroutine discharge.

CONCLUSIONS

In conclusion, our study demonstrates a negative association between noncirrhotic HCV infection and hip fracture surgery outcomes. Caution and appropriate preparation should be taken when surgically treating hip fractures in HCV+ patients because of higher risk of perioperative complications and nonroutine discharge.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Uncommon immune-mediated extrahepatic manifestations of HCV infection

INTRODUCTION

Chronic hepatitis C virus (HCV) infection has been associated with myriad extrahepatic manifestations, often resulting from aberrant immune responses. Among the most common immune-mediated manifestations of HCV infection, mixed cryoglobulinemia is the best known extra-hepatic complication. Areas covered: Here we review less common extrahepatic manifestations of HCV infection, with ascertained or presumed immune pathogenesis and the role of the new all oral direct-acting antiviral agents. Rheumatologic, dermatologic, ophthalmologic, renal, pulmonary, hematologic, cardiovascular, and neuropsychiatric manifestations of HCV infection have been considered. Expert commentary: Pathogenesis of HCV-induced aberrant immune responses resulting in peculiar clinical manifestations is not restricted to a single mechanism. A sound approach would therefore consider implementation of an etiologic treatment, through use of antiviral medications, to stop upstream in the pathogenic process all the immune mechanisms leading to hepatic and extrahepatic abnormalities. With the recent introduction of interferon-free, direct antiviral agents, capable of warranting cure for nearly all HCV-infected patients subjected to therapy, both common and uncommon extrahepatic manifestations of chronic hepatitis C are expected to no longer constitute a matter of comorbidity in the course of HCV infection.

Innate and Adaptive Immune Responses in Chronic HCV Infection

Hepatitis C virus (HCV) remains a public health problem of global importance, even in the era of potent directly-acting antiviral drugs. In this chapter, I discuss immune responses to acute and chronic HCV infection. The outcome of HCV infection is influenced by viral strategies that limit or delay the initiation of innate antiviral responses. This delay may enable HCV to establish widespread infection long before the host mounts effective T and B cell responses. HCV's genetic agility, resulting from its high rate of replication and its error prone replication mechanism, enables it to evade immune recognition. Adaptive immune responses fail to keep up with changing viral epitopes. Neutralizing antibody epitopes may be hidden by decoy structures, glycans, and lipoproteins. T cell responses fail due to changing epitope sequences and due to exhaustion, a phenomenon that may have evolved to limit immune-mediated pathology. Despite these difficulties, innate and adaptive immune mechanisms do impact HCV replication. Immune-mediated clearance of infection is possible, occurring in 20-50% of people who contract the disease. New developments raise hopes for effective immunological interventions to prevent or treat HCV infection.

Complication Rates After Total Hip and Knee Arthroplasty in Patients With Hepatitis C Compared With Matched Control Patients

BACKGROUND

A paucity of data exists regarding long-term outcomes among patients with hepatitis C who undergo total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

We queried a database for patients with hepatitis C who underwent THA and TKA. We then identified their rates of several postoperative complications and compared them with the same rates among mutually exclusive matched control cohorts.

RESULTS

Patients with hepatitis C who underwent THA and TKA had higher rates of infection, aseptic revision surgery, medical complications, and blood transfusion compared with matched control patients.

DISCUSSION

Our findings suggest that patients with hepatitis C who undergo THA and TKA are at increased risk of experiencing several postoperative complications, which could mean a substantial increase in the cost of care.

CONCLUSIONS

Further research is needed to establish quantifiable associations between hepatitis C and postoperative complications among patients with the disease who undergo total joint arthroplasty.

Dermatologic Manifestations of Chronic Hepatitis C Infection

Chronic hepatitis C virus (HCV) infection is associated with various extrahepatic manifestations, including dermatologic involvement mostly caused by immune complexes. Mixed cryoglobulinemia has a strong relationship with HCV with 95% of these patients being infected with HCV. Lichen planus is a disease of the squamous epithelium and may affect any part of the skin, with 4% to 24% of patients with lichen planus reported to have chronic HCV infection. Porphyria cutanea tarda is the most common form of porphyria, and it is thought that HCV interferes with iron stores, which can promote porphyria cutanea tarda. Finally, necrolytic acral erythema is a rare, psoriasis-like disease closely associated with HCV.

Type-I Interferon Responses: From Friend to Foe in the Battle against Chronic Viral Infection

Type I interferons (IFN-I) have long been heralded as key contributors to effective antiviral responses. More widely understood in the context of acute viral infection, the role of this pleiotropic cytokine has been characterized as triggering antiviral states in cells and potentiating adaptive immune responses. Upon induction in the innate immune response, IFN-I triggers the expression of interferon-stimulated genes (ISGs), which upregulate the effector function of immune cells (e.g., dendritic cells, B cells, and T cells) toward successful resolution of infections. However, emerging lines of evidence reveal that viral persistence in the course of chronic infections could be driven by deleterious immunomodulatory effects upon sustained IFN-I expression. In this setting, elevation of IFN-I and ISGs is directly correlated to viral persistence and elevated viral loads. It is important to note that the correlation among IFN-I expression, ISGs, and viral persistence may be a cause or effect of chronic infection and this is an important distinction to make toward establishing the dichotomous nature of IFN-I responses. The aim of this mini review is to (i) summarize the interaction between IFN-I and downstream effector responses and therefore (ii) delineate the function of this cytokine on positive and negative immunoregulation in chronic infection. This is a significant consideration given the current therapeutic administration of IFN-I in chronic viral infections whose therapeutic significance is projected to continue despite emergence of increasingly efficacious antiviral regimens. Furthermore, elucidation of the interplay between virus and the antiviral response in the context of IFN-I will elucidate avenues toward more effective therapeutic and prophylactic measures against chronic viral infections.

Is Hepatitis C Infection Associated With a Higher Risk of Complications After Total Shoulder Arthroplasty?

BACKGROUND

Despite recent advances in the treatment of hepatitis C, it is estimated that nearly 4 million Americans have a chronic form of the disease. Although research in lower-extremity arthroplasty suggests patients with hepatitis C are at risk for increased complications, including postoperative bleeding, acute postoperative infection, and general medical complications, no similar studies have investigated this question in patients undergoing total shoulder arthroplasty (TSA).

QUESTIONS/PURPOSES

We asked whether there is an increased risk of postoperative complications after TSA among patients who have hepatitis C, and if so, what complications in particular seem more likely to occur in this population?

METHODS

Patients who underwent TSA, including anatomic or reverse TSA, were identified in the PearlDiver database using ICD-9 procedure codes. This is a for-fee insurance patient-records database that contains more than 100 million individual patient records from 2005 to 2012. The Medicare data in the database are the complete 100% Medicare Standard Analytical File indexed to allow for patient tracking with time. Patients with hepatitis C who underwent shoulder arthroplasty then were identified using ICD-9 codes. Patients with hepatitis B coinfection or HIV were excluded. A control cohort of patients without hepatitis C who underwent TSA was created and matched to the study cohort based on age, sex, obesity, and diabetes mellitus. A total of 1466 patients with hepatitis C and 21,502 control patients were included. The two cohorts were statistically similar in terms of sex (53% females in study and control groups), age (nearly ½ of each cohort younger than 65 years), obesity (approximately 17% of each cohort were obese), diabetes (approximately 40% of each cohort had diabetes), and followup of each cohort occurred throughout the length of the database from 2005 to 2012. Postoperative complications were assessed using ICD-9 and Current Procedural Terminology codes and compared between cohorts.

RESULTS

Patients with hepatitis C, when compared with matched control subjects, had greater odds of infection within 3 months (odds ratio [OR], 1.7; 95% CI, 1.1-2.6; p = 0.015), 6 months (OR, 1.7; CI, 1.3-2.4; p = 0.001), and 1 year (OR, 2.1; CI, 1.7-2.7; p < 0.001); revision TSA within 1 year (OR, 1.5; CI, 1.1-2.9; p = 0.008) and 2 years (OR, 1.6; CI, 1.2-2.0; p = 0.001), dislocation within 1 year (OR, 1.6; CI, 1.2-2.2; p < 0.001); postoperative fracture within 1 year (OR, 1.8; CI, 1.2-2.6; p = 0.002); systemic or medical complications within 3 months (OR, 1.3; CI, 1.0-1.6; p = 0.022); and blood transfusion within 3 months (OR, 1.7; CI, 1.4-1.9; p < 0.001).

CONCLUSIONS

Hepatitis C is associated with an increased risk for complications after TSA, including infection, dislocation, fracture, revision TSA, systemic complications, and blood transfusion compared with matched control subjects. Although this study is able to identify increased odds of complications in patients with hepatitis C, the mechanism by which these occur is likely not solely related to the virus, and is more likely related to a higher degree of case complexity in addition to other postoperative socioeconomic factors.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Extra-hepatic infection of hepatitis C virus in the colon tissue and its relationship with hepatitis C virus pathogenesis

Extra-hepatic compartments might contribute to hepatitis C virus (HCV) persistence and extra-hepatic manifestations. Therefore, we investigated HCV infection in colonic tissue in patients with chronic hepatitis C (CHC) and its relationship with HCV pathogenesis. Colonic biopsies were collected from three groups with CHC infection: treatment naïve (TN; n=12), non-responders (NR; n=10) to anti-HCV therapy (pegylated interferon-α and ribavirin) and sustained virologic response (SVR; n=10) and from a fourth healthy control group (n=10). Liver biopsies were examined to assess inflammation and fibrosis. HCV infection and colonic T regulatory (Treg) frequency were detected by immunohistochemistry. HCV core and NS3 proteins were detected in B cells and macrophage/monocytes of 42 % and 25 % of TN and 50 % and 30 % of NR, respectively, but not in SVR or control group. The numbers of cells expressing HCV proteins were positively correlated with both HCV viral load and colonic Treg frequency. A significant negative correlation between HCV-expressing cells with both liver inflammation and fibrosis was identified. Our study provides evidence that HCV can infect B cells and macrophages of the colon. The correlations between HCV infection in colonic tissue and HCV viral load and liver pathology underline the significance of this extra-hepatic infection in HCV pathogenesis and response to therapy.

The pathophysiology of thrombocytopenia in chronic liver disease

Thrombocytopenia is the most common hematological abnormality encountered in patients with chronic liver disease (CLD). In addition to being an indicator of advanced disease and poor prognosis, it frequently prevents crucial interventions. Historically, thrombocytopenia has been attributed to hypersplenism, which is the increased pooling of platelets in a spleen enlarged by congestive splenomegaly secondary to portal hypertension. Over the past decade, however, there have been significant advances in the understanding of thrombopoiesis, which, in turn, has led to an improved understanding of thrombocytopenia in cirrhosis. Multiple factors contribute to the development of thrombocytopenia and these can broadly be divided into those that cause decreased production, splenic sequestration, and increased destruction. Depressed thrombopoietin levels in CLD, together with direct bone marrow suppression, result in a reduced rate of platelet production. Thrombopoietin regulates both platelet production and maturation and is impaired in CLD. Bone marrow suppression can be caused by viruses, alcohol, iron overload, and medications. Splenic sequestration results from hypersplenism. The increased rate of platelet destruction in cirrhosis also occurs through a number of pathways: increased shear stress, increased fibrinolysis, bacterial translocation, and infection result in an increased rate of platelet aggregation, while autoimmune disease and raised titers of antiplatelet immunoglobulin result in the immunologic destruction of platelets. An in-depth understanding of the complex pathophysiology of the thrombocytopenia of CLD is crucial when considering treatment strategies. This review outlines the recent advances in our understanding of thrombocytopenia in cirrhosis and CLD.

Total joint arthroplasty in patients with chronic infectious liver disease

The opportunity for total joint arthroplasty (TJA) in patients with chronic infectious liver disease is rapidly expanding. This is the product of both superior survival of chronic hepatitis patients, evolving implant technologies, and improvement of techniques in TJA. Unfortunately, treating this group of patients is not without significant challenges that can stem from both intrahepatic and extrahepatic clinical manifestations. Moreover, many subclinical changes occur in this cohort that can alter hemostasis, wound healing, and infection risk even in the asymptomatic patient. In this review, we discuss the various clinical presentations of chronic infectious liver disease and summarize the relevant literature involving total joint arthroplasty for this population. Hopefully, through appropriate patient selection and perioperative optimization, treating surgeons should see continued improvement in outcomes for patients with chronic infectious liver disease.

Evolution of the Humoral Response during HCV Infection: Theories on the Origin of Broadly Neutralizing Antibodies and Implications for Vaccine Design

Similar to human immunodeficiency virus (HIV)-1, vaccine-induced elicitation of broadly neutralizing (bNt) antibodies (Abs) is gaining traction as a key goal toward the eradication of the hepatitis C virus (HCV) pandemic. Previously, the significance of the Ab response against HCV was underappreciated given the prevailing evidence advancing the role of the cellular immune response in clearance and overall control of the infection. However, recent findings have driven growing interest in the humoral arm of the immune response and in particular the role of bNt responses due to their ability to confer protective immunity upon passive transfer in animal models. Nevertheless, the origin and development of bNt Abs is poorly understood and their occurrence is rare as well as delayed with emergence only observed in the chronic phase of infection. In this review, we characterize the interplay between the host immune response and HCV as it progresses from the acute to chronic phase of infection. In addition, we place these events in the context of current hypotheses on the origin of bNt Abs against the HIV-1, whose humoral immune response is better characterized. Based on the increasing significance of the humoral immune response against HCV, characterization of these events may be critical in understanding the development of the bNt responses and, thus, provide strategies toward effective vaccine design.

Clinical outcomes of cryptogenic compared with non-cryptogenic cirrhosis: A retrospective cohort study

BACKGROUND AND AIM

The consequences of the association between the metabolic syndrome and cryptogenic cirrhosis are uncertain. We aimed to compare the differences in clinical outcomes between cryptogenic and non-cryptogenic cirrhosis.

METHODS

A retrospective cohort study was conducted in a large, single academic center, over a 5-year duration.

RESULTS

Complete data were available in 301 patients with cirrhosis (cryptogenic n = 94, non-cryptogenic n = 207). Compared with non-cryptogenic cirrhosis, patients with cryptogenic cirrhosis were older (mean age 66.4 ± 12.5 vs 60.7 ± 11.3 years, P < 0.0001), had more females (43.6% vs 26.6%, P = 0.003), had less disease severity (Child-Pugh C 8.5% vs 15.9%, P = 0.042), and had a higher prevalence of the metabolic syndrome (83% vs 51.2%, P < 0.0001). During the 5-year period, adults with cryptogenic Child-Pugh A cirrhosis had a longer total hospital admission duration compared with non-cryptogenic cirrhosis (median 7.0 vs 3.0 days, P = 0.035), but this was less evident in patients with more advanced disease. This difference was due to a longer duration of hospitalization for non-liver-related morbidity (median 14.0 days vs 8.0 days, P = 0.04), rather than liver-related morbidity (median 10.5 days vs 8.0 days, P = 0.34), in patients with cryptogenic compared with non-cryptogenic cirrhosis. Kaplan-Meier survival analysis showed no significant differences in survival between both types of cirrhosis for all grades of severity.

CONCLUSIONS

Cryptogenic cirrhosis is associated with a longer duration of hospitalization compared with non-cryptogenic cirrhosis at an early stage of the disease. This difference is due to a greater burden of non-liver-related complications in the former.

Dermatologic Extrahepatic Manifestations of Hepatitis C

Hepatitis C virus (HCV) affects millions of people worldwide, and an estimated 3.2 million people in the United States. HCV is a hepatotropic and lymphotropic virus that causes not only liver disease, but also a significant number of extrahepatic manifestations (EHMs). Up to 74% of patients affected by HCV will have HCV-related EHMs of some severity in their lifetime. The EHMs vary from simple cutaneous palpable purpura to complex lymphoproliferative disorders, including lymphomas and immune-complex deposit diseases causing local and/or systemic complications. Mixed cryoglobulinemia (MC) is manifested by multiple systemic organ involvement, mainly skin, kidney, peripheral nerves, and salivary glands, and less frequently causes widespread vasculitis and malignant lymphoma. MC affects up to 3% of HCV-infected patients with cryoglobulinemia of clinical significance, i.e. >6%. Severe disease requires immunosuppressive or plasma exchange therapy. HCV prevalence in the United States in patients with porphyria cutanea tarda (PCT) was reported to be 66%, much higher than that in general population. Therefore, all patients with PCT should be screened for HCV. The skin rash of PCT varies from large blisters to small vesicles and/or milia on the hands. Skin manifestations due to PCT usually respond to anti-HCV treatment together with reducing skin sun exposure, avoiding triggers, having routine phlebotomy (especially for people with chronic iron overload states), and using chloroquine. Lichen planus (LP), which typically affects both the skin and oral mucosa is a chronic inflammatory disease of squamous cell origin affecting about 1% of the worldwide population. The prevalence of HCV in patients with LP varies based on geographic location. We review here the basic pathophysiology, clinical features, and management of dermatologic manifestations of HCV.

Skewed B cells in chronic hepatitis C virus infection maintain their ability to respond to virus-induced activation

Chronic hepatitis C virus (HCV) infection is characterized by persistent B-cell activation, with enhanced differentiation and reduced proliferative ability. To assess the possible role of HCV in altering B-cell subset distribution, we examined ex vivo frequencies and B-cell inhibitory receptor expression in 37 chronic HCV-infected patients and 25 healthy donors (HD). In addition, we determined whether short-term exposure to culture-derived HCV (HCVcc) resulted in B-cell subset skewing and/or activation. There was a statistically significant increase in the frequencies of immature transitional, activated memory and tissue-like memory (TLM) B cells in HCV-infected patients compared with HD. We also found that the frequency of memory B cells correlated with serum HCV RNA levels. The proportion of B cells expressing the marker of exhaustion Fc receptor-like 4 (FcRL4) was generally low even though significantly higher in the patients' memory B-cell compartment compared with HD, and a positive correlation was found between the frequencies of the patients' TLM FcRL4+ B cells and serum alanine aminotransferase and histological activity index at liver biopsy. Exposure to cell-free HCVcc in vitro did not result in B-cell skewing but induced significant activation of naïve, TLM and resting memory B cells in HCV-infected patients but not in HD, in whom cell-associated virus was an absolute requirement for activation of memory B cells. These findings provide corroborative evidence in favour of significant B-cell subset skewing in chronic HCV infection and in addition show that expression of exhaustion markers in selected B-cell subsets does not impair virus-induced B-cell activation.

Increase in perioperative complications following primary total hip and knee arthroplasty in patients with hepatitis C without cirrhosis

The effects of hepatitis C on primary total hip (THA) and knee (TKA) arthroplasties are poorly understood. The National Hospital Discharge Survey was used to identify patients who underwent THA or TKA between 1990 and 2007 without a diagnosis of cirrhosis, HIV, or hepatitis A, B, D or E virus infection. Patients were split into two groups: 1) hepatitis C (n=26,444) and 2) non-hepatitis C (n=8,336,882) and analyzed for differences in length of hospital stay, discharge status and perioperative complications. Those with hepatitis C had shorter hospital stays, higher rates of nonroutine discharge and higher odds of in-hospital complications (OR: 1.686, range: 1.645-1.727), surgery related complications (OR: 1.559, range: 1.516-1.603) and general medical complications (OR: 2.012, range: 1.961-2.064) (P<0.001).

Diabetes and Hepatitis C: A Two-Way Association

Diabetes and hepatitis C infection are both prevalent diseases worldwide, and are associated with increased morbidity and mortality. Most studies, but not all, have shown that patients with chronic hepatitis C are more prone to develop type 2 diabetes (T2D) compared to healthy controls, as well as when compared to patients with other liver diseases, including hepatitis B. Furthermore, epidemiological studies have revealed that patients with T2D may also be at higher risk for worse outcomes of their hepatitis C infection, including reduced rate of sustained virological response, progression to fibrosis and cirrhosis, and higher risk for development of hepatocellular carcinoma. Moreover, hepatitis C infection and mainly its treatment, interferon α, can trigger the development of type 1 diabetes. In this review, we discuss the existing data on this two-way association between diabetes and hepatitis C infection with emphasis on possible mechanisms. It remains to be determined whether the new curative therapies for chronic hepatitis C will improve outcomes in diabetic hepatitis C patients, and conversely whether treatment with Metformin will reduce complications from hepatitis C virus infection. We propose an algorithm for diabetes screening and follow-up in hepatitis C patients.

Hepatitis C virus infection and type 1 and type 2 diabetes mellitus

Hepatitis C virus (HCV) infection and diabetes mellitus are two major public health problems that cause devastating health and financial burdens worldwide. Diabetes can be classified into two major types: type 1 diabetes mellitus (T1DM) and T2DM. T2DM is a common endocrine disorder that encompasses multifactorial mechanisms, and T1DM is an immunologically mediated disease. Many epidemiological studies have shown an association between T2DM and chronic hepatitis C (CHC) infection. The processes through which CHC is associated with T2DM seem to involve direct viral effects, insulin resistance, proinflammatory cytokines, chemokines, and other immune-mediated mechanisms. Few data have been reported on the association of CHC and T1DM and reports on the potential association between T1DM and acute HCV infection are even rarer. A small number of studies indicate that interferon-α therapy can stimulate pancreatic autoimmunity and in certain cases lead to the development of T1DM. Diabetes and CHC have important interactions. Diabetic CHC patients have an increased risk of developing cirrhosis and hepatocellular carcinoma compared with non-diabetic CHC subjects. However, clinical trials on HCV-positive patients have reported improvements in glucose metabolism after antiviral treatment. Further studies are needed to improve prevention policies and to foster adequate and cost-effective programmes for the surveillance and treatment of diabetic CHC patients.

Peripheral nervous system manifestations of infectious diseases

Infectious causes of peripheral nervous system (PNS) disease are underrecognized but potentially treatable. Heightened awareness educed by advanced understanding of the presentations and management of these infections can aid diagnosis and facilitate treatment. In this review, we discuss the clinical manifestations, diagnosis, and treatment of common bacterial, viral, and parasitic infections that affect the PNS. We additionally detail PNS side effects of some frequently used antimicrobial agents.

Immune control and failure in HCV infection--tipping the balance

Despite the development of potent antiviral drugs, HCV remains a global health problem; global eradication is a long way off. In this review, we discuss the immune response to HCV infection and particularly, the interplay between viral strategies that delay the onset of antiviral responses and host strategies that limit or even eradicate infected cells but also contribute to pathogenesis. Although HCV can disable some cellular virus-sensing machinery, IFN-stimulated antiviral genes are induced in the infected liver. Whereas epitope evolution contributes to escape from T cell-mediated immunity, chronic high antigen load may also blunt the T cell response by activating exhaustion or tolerance mechanisms. The evasive maneuvers of HCV limit sterilizing humoral immunity through rapid evolution of decoy epitopes, epitope masking, stimulation of interfering antibodies, lipid shielding, and cell-to-cell spread. Whereas the majority of HCV infections progress to chronic hepatitis with persistent viremia, at least 20% of patients spontaneously clear the infection. Most of these are protected from reinfection, suggesting that protective immunity to HCV exists and that a prophylactic vaccine may be an achievable goal. It is therefore important that we understand the correlates of protective immunity and mechanisms of viral persistence.

Oral conditions associated with hepatitis C virus infection

Hepatitis C virus (HCV) infection in more than 170 million chronically infected patients with no developed preventive vaccine is a globally important issue. In addition to expected hepatic manifestations, a number of extrahepatic manifestations, such as mixed cryoglobulinemia, glomerulonephritis, polyarteritis nodosa, rashes, renal disease, neuropathy, and lymphoma, have been reported following HCV infection, which are believed to be influenced by the virus or the host immune response. HCV combination therapy with pegylated interferon and ribavirin might be associated with side effects as well. The association of HCV with special oral conditions has also been reported recurrently; the mechanism of most of which remains unclear. This article reviews the association of HCV infection with some of the oral conditions such as oral health, Sjogren's syndrome, lichen planus and oral cancer.

Primary, post-primary and non-specific immunoglobulin M responses in HCV infection

Delayed and variable antibody responses to HCV make it difficult to diagnose acute HCV infection reliably. Immunoglobulin (Ig)M and IgG anti-HCV may be observed simultaneously as disease persists. IgM plays a key role in mixed cryoglobulinemia (MC), an immune complex disease strongly associated with persistent HCV infection. In MC, clonal or oligoclonal IgM rheumatoid factors facilitate the deposition of immune complexes in small blood vessels and tissue, leading to inflammation, complement activation and tissue damage. Clonally expanded IgM(+)κ(+) B-cells expressing rheumatoid factor-like IgM are abundant in many HCV patients with MC. The observation that identical or similar IgM antibodies are expressed in different patients' clonally expanded B-cells supports the hypothesis that MC is driven by antigen-specific B-cell activation, rather than polyclonal B-cell activation or HCV replication in B-cells. More study is required to identify the antigens that drive the development of MC.

Extrahepatic manifestations and autoantibodies in patients with hepatitis C virus infection

Patients with chronic hepatitis C virus (HCV) infection frequently have many extrahepatic manifestations, as persistent HCV infection often triggers lymphoproliferative disorders and metabolic abnormalities. These manifestations primarily include autoimmune disorders such as cryoglobulinemia, Sjögren's syndrome, and autoimmune thyroid disorders. It has been well established that chronic HCV infection plays important roles in the production of non-organ-specific autoantibodies, including antinuclear antibodies and smooth muscle antibodies, and organ-specific autoantibodies such as thyroid autoantibodies. However, the clinical significance of autoantibodies associated with the extrahepatic manifestations caused by HCV infection has not been fully recognized. In this paper, we mainly focus on the relationship between extrahepatic manifestations and the emergence of autoantibodies in patients with HCV infection and discuss the clinical relevance of the autoantibodies in the extrahepatic disorders.

Extrahepatic manifestations and autoantibodies in patients with hepatitis C virus infection

Patients with chronic hepatitis C virus (HCV) infection frequently have many extrahepatic manifestations, as persistent HCV infection often triggers lymphoproliferative disorders and metabolic abnormalities. These manifestations primarily include autoimmune disorders such as cryoglobulinemia, Sjögren's syndrome, and autoimmune thyroid disorders. It has been well established that chronic HCV infection plays important roles in the production of non-organ-specific autoantibodies, including antinuclear antibodies and smooth muscle antibodies, and organ-specific autoantibodies such as thyroid autoantibodies. However, the clinical significance of autoantibodies associated with the extrahepatic manifestations caused by HCV infection has not been fully recognized. In this paper, we mainly focus on the relationship between extrahepatic manifestations and the emergence of autoantibodies in patients with HCV infection and discuss the clinical relevance of the autoantibodies in the extrahepatic disorders.

Extrahepatic manifestations and autoantibodies in patients with hepatitis C virus infection

Patients with chronic hepatitis C virus (HCV) infection frequently have many extrahepatic manifestations, as persistent HCV infection often triggers lymphoproliferative disorders and metabolic abnormalities. These manifestations primarily include autoimmune disorders such as cryoglobulinemia, Sjögren's syndrome, and autoimmune thyroid disorders. It has been well established that chronic HCV infection plays important roles in the production of non-organ-specific autoantibodies, including antinuclear antibodies and smooth muscle antibodies, and organ-specific autoantibodies such as thyroid autoantibodies. However, the clinical significance of autoantibodies associated with the extrahepatic manifestations caused by HCV infection has not been fully recognized. In this paper, we mainly focus on the relationship between extrahepatic manifestations and the emergence of autoantibodies in patients with HCV infection and discuss the clinical relevance of the autoantibodies in the extrahepatic disorders.

Hepatitis C virus-mediated modulation of cellular immunity

The hepatitis C virus (HCV) is a major cause of chronic liver disease globally. A chronic infection can result in liver fibrosis, liver cirrhosis, hepatocellular carcinoma and liver failure in a significant ratio of the patients. About 170 million people are currently infected with HCV. Since 80 % of the infected patients develop a chronic infection, HCV has evolved sophisticated escape strategies to evade both the innate and the adaptive immune system. Thus, chronic hepatitis C is characterized by perturbations in the number, subset composition and/or functionality of natural killer cells, natural killer T cells, dendritic cells, macrophages and T cells. The balance between HCV-induced immune evasion and the antiviral immune response results in chronic liver inflammation and consequent immune-mediated liver injury. This review summarizes our current understanding of the HCV-mediated interference with cellular immunity and of the factors resulting in HCV persistence. A profound knowledge about the intrinsic properties of HCV and its effects on intrahepatic immunity is essential to be able to design effective immunotherapies against HCV such as therapeutic HCV vaccines.

Immune-mediated myelitis associated with hepatitis virus infections

Virus-induced spinal cord damage results from a cytolytic effect on anterior horn cells or from predominantly cellular immune-mediated damage of long white matter tracts. Infection with the hepatitis virus group, most notably hepatitis C virus, has infrequently been associated with the occurrence of myelitis. The pathogenesis of hepatitis virus-associated myelitis has not been clarified: virus-induced autoimmunity (humoral or cell-mediated, possibly vasculitic) seems the most likely disease mechanism. Limited available information offers no evidence of direct hepatitis virus infection of the spinal cord. Virus neuropenetration may occur after virus-infected mononuclear cells penetrate the blood-brain barrier, but a true neurolytic effect has not been demonstrated. Attacks of acute myelitis usually respond favorably to immunomodulatory therapy. Antiviral therapy plays no confirmed role in the treatment of acute bouts of myelitis, but may limit the relapsing course of HCV-associated myelitis.

Total joint arthroplasty in patients with hepatitis C

BACKGROUND

Hepatitis C is present worldwide. Little is known about the outcome of joint arthroplasty in asymptomatic patients with hepatitis C. We evaluated the surgical complications following hip and knee arthroplasty in patients who were seropositive for hepatitis C in a matched study.

METHODS

Seventy-one patients with hepatitis C underwent forty total hip arthroplasties and thirty-two total knee arthroplasties from 1995 to 2006. The patients had normal preoperative liver function tests. Patients with human immunodeficiency virus infection, hepatitis B, and hemophilia were excluded. A control group was matched in a 2:1 ratio with the hepatitis-C group for age, body-mass index, sex, year of surgery, and medical comorbidities, including diabetes, rheumatoid arthritis, and immunosuppressive conditions.

RESULTS

In the group of patients with hepatitis C who were managed with total hip arthroplasty, six patients (15%) had wound complications requiring oral antibiotics or wound irrigation and debridement and four hips (10%) had mechanical complications, including implant loosening or dislocation. In the control group, three patients (3.8%) had wound complications requiring oral antibiotics or irrigation and debridement and three patients (3.8%) had mechanical complications, including dislocation, periprosthetic femoral fracture, and implant failure. In the group of patients with hepatitis C who underwent total knee arthroplasty, three patients (9.4%) had mechanical complications, including loosening and periprosthetic fracture requiring revision. In the control group, three patients (4.7%) had wound complications, one (1.6%) had a deep infection requiring two-stage revision, and one (1.6%) underwent revision because of a mechanical problem. The combined hepatitis-C group had significantly longer hospital stays and higher rates of surgical and mechanical complications, reoperation, and revision.

CONCLUSIONS

Patients with hepatitis C undergoing joint arthroplasty had a higher rate of surgical complications and a longer hospital stay. The reason for the higher rate of complications in this group of patients is unknown, and further investigation is needed. Patients with hepatitis C should be counseled about the potential for a higher incidence of postoperative complications prior to undergoing joint arthroplasty.

Viral interactions with B-cells contribute to increased regulatory T-cells during chronic HCV infection

Hepatitis C virus (HCV) has a propensity to establish chronic infection that is characterized by attenuated virus-specific T-cell responses. Mechanisms leading to T-cell attenuation are poorly understood and likely involve dysfunctional interactions between antigen-presenting cells (APC) and effector/regulatory T-cells. Reports on dendritic cells (DC) have described only minor dysfunction during HCV infection. However, there is a paucity of reports regarding B-cell function, despite clear associations with B-cell-related secondary sequelae. In this study we evaluated the state of B-cells during chronic HCV infection, and observed a diminished ability to respond to mitogenic stimuli, correlating with increased apoptosis. This was in contrast to their ex vivo phenotype, which indicated ongoing chronic activation in vivo. There was a high association of HCV-positive strand RNA with B-cells in a subset of HCV patients. Interestingly, ex-vivo-derived HCV RNA-positive B-cells induced significantly greater proliferation in allogeneic T-cells than in HCV-negative B-cells, correlating with an increased generation of CD4(+)CD25(+)FOXP3(+) regulatory T-cells (Tregs). In-vitro exposure of healthy peripheral blood mononuclear cells (PBMC) to HCV resulted in robust activation of resting B-cells. These HCV-exposed B-cells also showed an enhanced ability to generate Tregs. Our results provide strong evidence for a novel and paradoxical link between HCV-induced enhanced APC function and the generation of Tregs.

A case of hepatitis C-associated osteosclerosis that was improved with the combination therapy of peginterferon alfa-2b and ribavirin

Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in skeletal mass in patients who are infected with hepatitis C virus (HCV). The clinical presentation is an acquired deep bone pain with increased serum alkaline phosphatase (ALP) activity. We present a case of a patient with HCAO who was treated with antiviral therapy. A 42-year-old Japanese man presented with severe, stabbing pain in his lower limbs. He was diagnosed with hepatitis C secondary to intravenous drug use 20 years earlier. Serum biochemical studies revealed markedly elevated ALP activity and osteocalcin levels. Skeletal radiographs showed diffuse bony sclerosis with marked cortical thickening in the long bones. The bony findings and clinical symptoms were attributed to HCAO. The HCV RNA viral load was high and the genotype was 2a. The patient was treated with peginterferon alfa-2b and ribavirin for 24 weeks. After 24 weeks of the combination therapy, the patient had a sustained virological response and clinical remission of bone pain and a decrease in the level of serum ALP. In conclusion, HCAO was improved by the combination therapy of peginterferon alfa-2b and ribavirin when the patient achieved sustained virological response. It was confirmed that HCAO was one of the extrahepatic manifestations of HCV.

The prevalence of gestational diabetes mellitus and glucose abnormalities in pregnant women with hepatitis C virus infection in British Columbia

OBJECTIVE

There is evidence to support an association between diabetes mellitus (DM) and hepatitis C virus (HCV) infection. The insulin resistant state of pregnancy suggests a predisposition to developing gestational diabetes mellitus (GDM) in women infected with HCV. The aim of this study was to compare the prevalence of GDM and impaired glucose tolerance (IGT) of pregnancy between women infected with HCV and the general population of British Columbia screened for GDM.

METHODS

The HCV cohort was drawn from a population-based prospective cohort of 148 pregnant women infected with HCV in British Columbia. GDM screening tests were completed in 84 women. The prevalence of GDM and IGT of pregnancy in the general population of British Columbia was estimated by acquiring 24 321 GDM screening tests performed by the two major laboratories in the province.

RESULTS

Non-compliance was the primary reason for incomplete screening. The prevalence of GDM was 9.5% in the HCV cohort and 6.8% in the screened general population (chi-square test P = 0.33). Similarly, there was no difference in IGT of pregnancy between the two cohorts (2.4% vs. 3.5%; chi-square test P = 0.57).

CONCLUSION

A difference in the prevalence of either GDM or IGT of pregnancy was not detected between HCV-infected patients who were screened for GDM and those screened in the general population. Further studies are required to assess whether HCV infection is an independent risk factor for GDM.

Hepatitis C: the complications of immune dysfunction

Hepatitis C virus (HCV) infection has been linked to numerous diseases of immune dysfunction, including, but not limited to, essential mixed cryoglobulinemia and non-Hodgkin's lymphoma. Clinical studies support these associations and treatment of the underlying HCV infection has been variably successful. Recent studies, focusing on the role of HCV gene products, have discovered evidence of dysregulated responses in multiple aspects of host immunity that may be contributing to the genesis of these diseases. Novel treatments that target these areas of dysregulation offer hope for improved therapy for the diseases associated with immunodysregulation by HCV.

Management of hepatitis C virus-related mixed cryoglobulinemia

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