Autoimmune hepatitis and primary sclerosing cholangitis after direct-acting antiviral treatment for hepatitis C virus:A case report

BACKGROUND Chronic hepatitis C virus(HCV)infection is a major global health concern that leads to liver fibrosis,cirrhosis,and cancer.Regimens containing direct-acting antivirals(DAAs)have become the mainstay of HCV treatment,achieving a high sustained virological response(SVR)with minimal adverse events.CASE SUMMARY A 74-year-old woman with chronic HCV infection was treated with the DAAs ledipasvir,and sofosbuvir for 12 wk and achieved SVR.Twenty-four weeks after treatment completion,the liver enzyme and serum IgG levels increased,and antinuclear antibody became positive without HCV viremia,suggesting the development of autoimmune hepatitis(AIH).After liver biopsy indicated AIH,a definite AIH diagnosis was made and prednisolone was initiated.The treatment was effective,and the liver enzyme and serum IgG levels normalized.However,multiple strictures of the intrahepatic and extrahepatic bile ducts with dilatation of the peripheral bile ducts appeared on magnetic resonance cholangiopancreatography after 3 years of achieving SVR,which were consistent with primary sclerosing cholangitis.CONCLUSION The potential risk of developing autoimmune liver diseases after DAA treatment should be considered.

Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis progression.The assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWE).Liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with DAAs.AIM To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus(HCV).METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV clearance.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(LS)in those who go on to develop HCC compared to those who do not[baseline LS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;LS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source data.There was a statist-ically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONCLUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with DAAs.Further studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

Ensemble for evaluating diagnostic efficacy of non-invasive indices in predicting liver fibrosis in untreated hepatitis C virus population

BACKGROUND Hepatitis C virus(HCV)infection progresses through various phases,starting with inflammation and ending with hepatocellular carcinoma.There are several invasive and non-invasive methods to diagnose chronic HCV infection.The invasive methods have their benefits but are linked to morbidity and complications.Thus,it is important to analyze the potential of non-invasive methods as an alternative.Shear wave elastography(SWE)is a non-invasive imaging tool widely validated in clinical and research studies as a surrogate marker of liver fibrosis.Liver fibrosis determination by invasive liver biopsy and non-invasive SWE agree closely in clinical studies and therefore both are gold standards.AIM To analyzed the diagnostic efficacy of non-invasive indices[serum fibronectin,aspartate aminotransferase to platelet ratio index(APRI),alanine aminotransferase ratio(AAR),and fibrosis-4(FIB-4)]in relation to SWE.We have used an Artificial Intelligence method to predict the severity of liver fibrosis and uncover the complex relationship between non-invasive indices and fibrosis severity.METHODS We have conducted a hospital-based study considering 100 untreated patients detected as HCV positive using a quantitative Real-Time Polymerase Chain Reaction assay.We performed statistical and probabilistic analyses to determine the relationship between non-invasive indices and the severity of fibrosis.We also used standard diagnostic methods to measure the diagnostic accuracy for all the subjects.RESULTS The results of our study showed that fibronectin is a highly accurate diagnostic tool for predicting fibrosis stages(mild,moderate,and severe).This was based on its sensitivity(100%,92.2%,96.2%),specificity(96%,100%,98.6%),Youden’s index(0.960,0.922,0.948),area under receiver operating characteristic curve(0.999,0.993,0.922),and Likelihood test(LR+>10 and LR-<0.1).Additionally,our Bayesian Network analysis revealed that fibronectin(>200),AAR(>1),APRI(>3),and FIB-4(>4)were all strongly associated with patients who had severe fibrosis,with a 100% probability.CONCLUSION We have found a strong correlation between fibronectin and liver fibrosis progression in HCV patients.Additionally,we observed that the severity of liver fibrosis increases with an increase in the non-invasive indices that we investigated.

Peginterferon and ribavirin treatment for hepatitis C virus infection

Pegylated interferon α (IFNα) in combination with ribavirin is currently recommended as a standard-of-care treatment for chronic hepatitis C virus (HCV) infection. This combination therapy has drastically improved the rate of sustained virological response, specifically in difficult-to-treat patients. Recently, individualized treatment, such as response-guided therapy, is being developed based on host-, HCV- and treatment-related factors. Furthermore, modified regimens with currently available medications, novel modified IFNα and ribavirin or combinations with specifically targeted antiviral therapy for HCV agents, are currently being investigated. The purpose of this review is to address some issues and epoch-making topics in the treatment of chronic HCV infection, and to discuss more optimal and highly individualized therapeutic strategies for HCV-infected patients.

Chronic hepatitis C genotype 1 virus:Who should wait for treatment?

Elucidation of the natural history of chronic hepatitis C (CHC) and the identification of risk factors for its progression to advanced liver disease have allowed many physicians to recommend deferral treatment (triple therapy) in favour of waiting for new drug availability for patients who are at low risk of progression to significant liver disease. Newer generation drugs are currently under development, and are expected to feature improved efficacy and safety profiles, as well as less complex and shorter duration delivery regimens, compared to the current standards of care. In addition, patients with cirrhosis and prior null responders have a low rate (around 15%) of achieving sustained virological response (SVR) with triple therapy, and physicians must also consider the decision to wait for new treatments in the future for these patients as well. Na&#x000ef;ve patients are the most likely to achieve a close to 100% SVR rate; therefore, it may be advisable to recommend that patients with mild to moderate CHC should wait for the newer therapy options. In contrast, patients with advanced fibrosis and cirrhosis will be those with the greatest need for expedited therapeutic intervention. There remains a need, however, for establishing definitive clinical management guidelines to maximize the benefit of waiting for new drugs and minimize risk of side effects and non-response to the current triple therapy.

Desperately seeking hepatitis C virus

Spanish investigators described recently the so-called occult hepatitis C virus (HCV) infection, emphasizing the detection of genomic and antigenomic HCV RNA strands in liver and peripheral blood mononuclear cells. Therefore, the persistence of viral replication in occult HCV infection should be considered as a putative source of infection among family members and patients undergoing invasive procedures, transfusion or transplantation. Additionally, the most worrisome finding is that an occult HCV infection may persist in patients with sustained virological response.

Understanding the interaction of hepatitis C virus with host DEAD-box RNA helicases

The current therapeutic regimen to combat chronic hepatitis C is not optimal due to substantial side effects and the failure of a significant proportion of patients to achieve a sustained virological response. Recently developed direct-acting antivirals targeting hepatitis C virus (HCV) enzymes reportedly increase the virologic response to therapy but may lead to a selection of drug-resistant variants. Besides direct-acting antivirals, another promising class of HCV drugs in development include host targeting agents that are responsible for interfering with the host factors crucial for the viral life cycle. A family of host proteins known as DEAD-box RNA helicases, characterized by nine conserved motifs, is known to play an important role in RNA metabolism. Several members of this family such as DDX3, DDX5 and DDX6 have been shown to play a role in HCV replication and this review will summarize our current knowledge on their interaction with HCV. As chronic hepatitis C is one of the leading causes of hepatocellular carcinoma, the involvement of DEAD-box RNA helicases in the development of HCC will also be highlighted. Continuing research on the interaction of host DEAD-box proteins with HCV and the contribution to viral replication and pathogenesis could be the panacea for the development of novel therapeutics against HCV.

Hepatic steatosis as a possible risk factor for the development of hepatocellular carcinoma after eradication of hepatitis C virus with antiviral therapy in patients with chronic hepatitis C

AIM: To elucidate risk factors contributing to the development of hepatocellular carcinoma (HCC) among patients with sustained viral response (SVR) after interferon (IFN) treatment and to examine whether HCV-RNA still remained in the liver of SVR patients who developed HCC. METHODS: Two-hundred and sixty-six patients, who achieved SVR, were enrolled in this study. We retrospectively reviewed clinical, viral and histological features of the patients, and examined whether the development of HCC depends on several clinical variables using Kaplan-Meier Method. RT-PCR was used to seek HCV-RNA in 3 out of 7 patients in whom liver tissue was available for molecular analysis. RESULTS: Among the enrolled 266 patients with SVR, HCC developed in 7 patients (7/266; 2.6%). We failed to detect HCV-RNA both in cancer and non-cancerous liver tissue in all three patients. The cumulative incidence for HCC was significantly different depending on hepatic fibrosis (F3-4) (P = 0.0028), hepatic steatosis (Grade 2-3) (P = 0.0002) and age (≥ 55) (P = 0.021) at the pre-interferon treatment. CONCLUSION: The current study demonstrated that age, hepatic fibrosis, and hepatic steatosis at pre- interferon treatment might be risk factors for developing HCC after SVR.

Distribution of different hepatitis C virus genotypes in patients with hepatitis C virus infection

AIM:To investigate the presence of mixed infection and discrepancy between hepatitis C virus(HCV) genotypes in plasma,peripheral blood mononuclear cells(PBMCs),and liver biopsy specimens.METHODS:From September 2008 up to April 2009,133 patients with chronic hepatitis C referred to Firouzgar Hospital for initiation of an antiviral therapy were recruited in the study.Five milliliters of peripheral blood was collected from each patient and liver biopsy was performed in those who gave consent or had indications.HCV genotyping was done using INNO-LiPATM HCV in serum,PBMCs,and liver biopsy specimens and then conf irmed by sequencing of 5'-UTR fragments.RESULTS:The mean age of patients was 30.3 ± 17.1 years.Multiple transfusion was seen in 124(93.2%) of patients.Multiple HCV genotypes were found in 3(2.3%) of 133 plasma samples,9(6.8%) of 133 PBMC samples,and 8(18.2%) of 44 liver biopsy specimens.It is notable that the different genotypes found in PBMCs were not the same as those found in plasma and liver biopsy specimens.CONCLUSION:Our study shows that a signif icant proportion of patients with chronic hepatitis C are affected by multiple HCV genotypes which may not be detectable only in serum of patients.

Hepatic flares in chronic hepatitis C: Spontaneous exacerbation vs hepatotropic viruses superinfection

The hepatitis C virus(HCV)causes an acute infection that is frequently asymptomatic,but a spontaneous eradication of HCV infection occurs only in one-third of patients.The remaining two-thirds develop a chronic infection that,in most cases,shows an indolent course and a slow progression to the more advanced stagesof the illness.Nearly a quarter of cases with chronic hepatitis C(CHC)develop liver cirrhosis with or without hepatocellular carcinoma.The indolent course of the illness may be troubled by the occurrence of a hepatic flare,i.e.,a spontaneous acute exacerbation of CHC due to changes in the immune response,immunosuppression and subsequent restoration,and is characterized by an increase in serum aminotransferase values,a frequent deterioration in liver fibrosis and necroinflammation but also a high frequency of sustained viral response to pegylated interferon plus ribavirin treatment.A substantial increase in serum aminotransferase values during the clinical course of CHC may also be a consequence of a superinfection by other hepatotropic viruses,namely hepatitis B virus(HBV),HBV plus hepatitis D virus,hepatitis E virus,cytomegalovirus,particularly in geographical areas with high endemicity levels.The etiology of a hepatic flare in patients with CHC should always be defined to optimize follow-up procedures and clinical and therapeutic decisions.

New perspectives in occult hepatitis C virus infection

Occult hepatitis C virus (HCV) infection, defined as the presence of HCV RNA in liver and in peripheral blood mononuclear cells (PBMCs) in the absence of detectable viral RNA in serum by standard assays, can be found in anti-HCV positive patients with normal serum levels of liver enzymes and in anti-HCV negative patients with persistently elevated liver enzymes of unknown etiology. Occult HCV infection is distributed worldwide and all HCV genotypes seem to be involved in this infection. Occult hepatitis C has been found not only in anti-HCV positive subjects with normal values of liver enzymes or in chronic hepatitis of unknown origin but also in several groups at risk for HCV infection such as hemodialysis patients or family members of patients with occult HCV. This occult infection has been reported also in healthy populations without evidence of liver disease. Occult HCV infection seems to be less aggressive than chronic hepatitis C although patients affected by occult HCV may develop liver cirrhosis and even hepatocellular carcinoma. Thus, anti-HCV negative patients with occult HCV may benefit from antiviral therapy with pegylated-interferon plus ribavirin. The persistence of very low levels of HCV RNA in serum and in PBMCs, along with the maintenance of specific T-cell responses against HCV-antigens observed during a long-term follow-up of patients with occult hepatitis C, indicate that occult HCV is a persistent infection that is not spontaneously eradicated. This is an updated report on diagnosis, epidemiology and clinical implications of occult HCV with special emphasis on anti-HCV negative cases.

Impact of virus genotype on interferon treatment of patients with chronic hepatitis C: a multicenter controlled study

BACKGROUND: Some factors have been reported to besassociated with a greater likelihood of sustained viral re-sponse ( SVR) in the interferon (IFN) treatment of chronichepatitis C. The factors include HCV genotype, HCVRNA level in serum, state of liver disease, baseline bodyweight, age, sex, and race. The aim of this trial was to in-vestigate the influence of HCV genotype on the IFN treat-ment of patients with chronic hepatitis C.METHODS: The genotypes of HCV virus were determinedin the patients with chronic hepatitis C from several hospi-tals of China enrolled into the randomized, opened andcontrolled trial of Peg-IFN alpha-2a (pegasys) treatment,controlled with IFN-α-2a (roferon-A). The serum ALTlevels and HCV RNA concentrations of the patients weredetected before and at the end of treatment and during thefollow-up. The influence of HCV genotype on the IFNtreatment of patients with chronic hepatitis C was analyzedin intention-to-treat (ITT) population.RESULTS: The HCV genotypes of 202 patients were deter-mined. Of these patients, 158(78.22%) were infected withgenotype 1 HCV and 44(21.78%) with genotype non-1.The viral response at the end of treatment (ETVR) andsustained viral response (SVR) rates were 53.80% and25.32% respectively in patients with genotype 1 HCV, butthey were 61.36% and 43.18% in patients with genotypenon-1. The difference of SVR between patients with geno-type 1 HCV and those with genotype non-1 was significant(P =0.021). After being grouped by the used drugs, theETVR rates of patients infected with genotype 1 and non-1HCV were 76.83% and 80.95% in the patients treated withpegasys (P =0.686); but their SVR rates were 35.37% and66.67% (P =0. 01). The viral relapse rate of genotype 1HCV (55.56%) was significantly higher than that of geno-type non-1 HCV (23.53%) (P=0.02). In roferon-A group,the ETVR and SVR rates of patients with genotype 1 HCVwere 28.95% and 14.47% respectively, which were lowerbut not more significant than those of patients with geno-type non-1 HCV (43.48% and 21.74%). Moreover, the vi-ral relapse rate of genotype 1 HCV (72.73%) was higherbut not more significant than that of genotype non-1 HCV(50.00%) (P=0.21).CONCLUSION: HCV genotype could affect the efficacies,mainly sustained responses, of IFN treatment in patientswith chronic hepatitis C, and the effects of IFN are relatedto drugs and therapeutic course.

Occult persistence and lymphotropism of hepatitis C virus infection

Recent discovery of occult hepatitis C virus (HCV) infection persisting after spontaneous or antiviral therapy-induced resolution of hepatitis C was made possible by the introduction of nucleic acid amplification assays capable of detecting HCV RNA at sensitivities superseding those offered by clinical tests. Although individuals with this seemingly silent HCV infection are usually anti-HCV antibody reactive and have normal liver function tests, occult HCV infection has also been reported in anti-HCV-negative individuals with persistently elevated liver enzymes of unknown etiology. Studies have shown that HCV RNA can persist for years in serum, lymphomononuclear cells and liver in the absence of clinical symptoms, although histological evidence of a mild inflammatory liver injury can be occasionally encountered. Furthermore, while HCV RNA can be detected in circulating lymphoid cells in approximately 30% of cases, a short-term culture under stimulatory conditions augments HCV replication in these cells allowing detection of virus in otherwise HCV-negative cases. HCV infects different immune cell subsets, including CD4+ and CD8+ T lymphocytes, B cells and monocytes. Studies employing clonal sequencing and single-stranded conformational polymorphism analyses have revealed unique HCV variants residing in immune cells, further strengthening the notion of HCV lymphotropism. Overall, the data accumulated suggest that occult HCV infection is a common consequence of resolution of symptomatic hepatitis C and that examination of the cells of the immune system is an effective approach to diagnosis of HCV infection and its long-term persistence. Further work is required to fully realize pathogenic and epidemiological consequences of occult HCV persistence.

Specifically targeted antiviral therapy for hepatitis C virus

Hepatitis C virus （HCV） infection affects 180 million people worldwide with the predominant prevalence being infection with genotype 1, followed by genotypes 2 and 3. Standard anti-HCV therapy currently aims to enhance natural immune responses to the virus, whereas new therapeutic concepts directly target HCV RNA and viral enzymes or influence host-virus interactions. Novel treatment options now in development are focused on inhibitors of HCV- specific enzymes, NS3 protease and NS5B polymerase. These agents acting in concert represent the concept of specifically targeted antiviral therapy for HCV （STAT-C）. STAT-C is an attractive strategy in which the main goal is to increase the effectiveness of antiviral responses across all genotypes, with shorter treatment duration and better tolerability. However, the emergence of resistant mutations that limit the use of these compounds in monotherapy complicates the regimens. Thus, a predictable scenario for HCV treatment in the future will be combinations of drugs with distinct mechanisms of action. For now, it seems that interferon will remain a fundamental component of any new anti-HCV therapeutic regimens in the near future; therefore, there is pressure to develop forms of interferon that are more effective, less toxic, and more convenient than pegylated interferon.

Serum manganese superoxide dismutase and thioredoxin are potential prognostic markers for hepatitis C virus-related hepatocellular carcinoma

AIM:To evaluate the clinical significance of oxidative stress markers in patients with hepatitis C virus(HCV)related hepatocellular carcinoma(HCC).METHODS:Sixty-four consecutive patients who were admitted to Kagoshima University Medical and Dental Hospital were enrolled in this retrospective study.All patients had chronic liver disease(CLD) due to infection with HCV.Thirty patients with HCV-related HCC,34 with HCV-related CLD without HCC(non-HCC),and 20 healthy volunteers(HVs) were enrolled.Possible associations between serum manganese superoxide dismutase(MnSOD) and thioredoxin(TRX) levels and clinical parameters or patient prognosis were analyzed over a mean follow-up period of 31.7 mo.RESULTS:The serum MnSOD levels were significantly higher in patients with HCV-related HCC than in patients without HCC(P = 0.03) or HVs(P < 0.001).Similarly,serum TRX levels were also significantly higher in patients with HCV-related HCC than in patients without HCC(P = 0.04) or HVs(P < 0.01).However,serum levels of MnSOD and TRX were not correlated in patients with HCC.Among patients with HCC,the overall survival rate(OSR) was lower in patients with MnSOD levels ≥ 110 ng/mL than in patients with levels < 110 ng/mL(P = 0.01),and the OSR tended to be lower in patients with TRX levels < 80 ng/mL(P = 0.05).In addition,patient prognosis with HCC was poorest with serum MnSOD levels ≥ 110 ng/mL and serum TRX levels < 80 ng/mL.Furthermore,a multivariate analysis using a Cox proportional hazard model and serum levels of five factors(MnSOD,prothrombin time,serum albumin,serum α-fetoprotein(AFP),and serum des-γ-carboxy prothrombin) revealed that MnSOD levels ≥ 110 ng/mL(risk ratio:4.12,95% confidential interval:1.22-13.88,P = 0.02) and AFP levels ≥ 40 ng/mL(risk ratio:6.75;95% confidential interval:1.70-26.85,P < 0.01) were independent risk factors associated with a poor patient prognosis.CONCLUSION:Serum MnSOD and TRX levels are potential clinical biomarkers that predict patient prognosis in HCV-related HCC.

Adaptive immune response during hepatitis C virus infection

Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma.HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control.Liver damage and disease progression during HCV infection are driven by both viral and host factors.Specifically,adaptive immune response carries out an essential task in controllingnon-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery.HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion.To impair HCV-specific T cell reactivity,HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro-and antiapoptotic proteins.In this review,the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.

Beneficial effects of fucoidan in patients with chronic hepatitis C virus infection

AIM:To evaluate the effects of fucoidan,a complex sulfated polysaccharide extract from marine seaweed,on hepatitis C virus(HCV) RNA load both in vitro and in vivo.METHODS:HCV-1b replicon-expressing cells were cultured in the presence of fucoidan obtained from Cladosiphon okamuranus Tokida cultivated in Okinawa,Japan,and quantified the level of HCV replication.In an open-label uncontrolled study,15 patients with chronic hepatitis C,and HCV-related cirrhosis and hepatocellular carcinoma were treated with fucoidan(0.83 g/d) for 12 mo.The clinical symptoms,biochemical tests,and HCV RNA levels were assessed before,during,and after treatment.RESULTS:Fucoidan dose-dependently inhibited the expression of HCV replicon.At 8-10 mo of treatment with fucoidan,HCV RNA levels were significantly lower relative to the baseline.The same treatment also tended to lower serum alanine aminotransferase levels,and the latter correlated with HCV RNA levels.However,the improved laboratory tests did not translate into significant clinical improvement.Fucoidan had no serious adverse effects.CONCLUSION:Our findings suggest that fucoidan is safe and useful in the treatment of patients with HCVrelated chronic liver diseases.Further controlled clinical trials are needed to confirm the present findings.

Current treatment for hepatitis C virus/human immunodeficiency virus coinfection in adults

Hepatitis C virus(HCV)/human immunodeficiency virus(HIV)coinfection is a major problem among HIV-infected patients,resulting in increased morbidity and mortality rates due to the acceleration of liver fibrosis progression by HIV,leading to liver cirrhosis and hepatocellular carcinoma.Although the efficacy of directacting antiviral therapy in patients with HIV/HCV coinfection and HCV monoinfection are similar in terms of sustained virologic response rate,there are some additional complications that arise in the treatment of patients with HIV/HCV coinfection,including drug-drug interactions and HCV reinfection due to the high risk behavior of these patients.This review will summarize the current management of HIV/HCV coinfection.

Sequencing of hepatitis C virus cDNA with polymerase chain reaction directed sequencing *

AIM To explore a rapid and easy sequencing method for hepatitis C virus (HCV) genome, and establish a new sequencing method in China. METHODS Polymerase Chain Reaction (PCR) was combined with DNA sequencing technique. PCR products were purified by agarose gel electrophoresis, polyacrylamide gel electrophoresis (PAGE), Polyethylene glycol (PEG) respectively. Then in the presence of a 5′ labeling PCR primer, purified PCR products were directly sequenced. By this method, HCV NS5b cDNA from two HCV infected individuals (HC 42 and HC 49) were sequenced.

Efficacy and tolerability of low-dose interferon-α in hemodialysis patients with chronic hepatitis C virus infection

AIM: To evaluate the efficacy and tolerability of low-dose standard or pegylated interferon (PEG-IFN) in hepatitis C virus (HCV)-positive hemodialysis patients.