Dual chronic hepatitis B virus and hepatitis C virus infection

Dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are common in HBV or HCV endemic areas. However, several clinical and pathogenetic issues remain unresolved. First, clinical and in vitro studies suggest the interactions between two viruses. The dynamics of the interaction in untreated setting versus treated setting and its influence on the long-term outcomes await further studies. A key issue regarding viral interactions is whether modulation of infection occurs in the same dually infected individual hepatocyte of the liver. Clarifying this issue may help to understand the reciprocal interference between HCV and HBV and provide clues for future immunopathogenetic studies. Second, the prevalence and clinical significance of coexisting occult HBV infection in patients with chronic HCV infection need further investigations. Third, combination therapy of peginterferon alfa-2a and ribavirin appears to be just as effective and safe for the treatment of hepatitis B surface antigen (HBsAg)-positive patients chronically infected with active chronic hepatitis C as it is in patients with HCV monoinfection. Nevertheless, one-third of dually infected patients with nondetectable serum HBV DNA-level pretreatment developed HBV reactivation posttreatment. How to prevent and treat this reactivation should be clarified. Furthermore, about 10% of the dually infected patients lost HBsAg. Underlying mechanisms await further investigations. Finally, the optimal treatment strategies for dually infected patients with hepatitis B e antigen-positive chronic hepatitis B should be identified in future clinical trials.     

Updates on the treatment and outcomes of dual chronic hepatitis C and B virus infection

Dual hepatitis C virus(HCV)/hepatitis B virus(HBV)infection is found in HBV or HCV endemic areas,and in specific populations exhibiting a high risk of parenteral viral transmission.Clinical observations have revealed that HCV/HBV dually infected patients demonstrate a higher risk of liver disease progression compared with HBV or HCV monoinfected patients.The viral activity responsible for liver disease progression can be determined by examining the viral loads of HCV and HBV and by conducting liver biopsy examinations.Recent trials have confirmed that the combination therapy of peginterferon alpha-2a or 2b and ribavirin for dual hepatitis patients with HCV dominance appears to be as effective and safe as it is in patients with HCV monoinfections.Strikingly,approximately 60% of dually infected patients with inactive hepatitis B before treatment develop HBV reactivation after the clearance of the HCV.The clinical significance of this HBV reactivation and the strategy to prevent and treat this event should be determined.Furthermore,approximately 30%of dually infected patients lost hepatitis B surface antigen(HBsAg)within 5 years after the start of peginterferonbased therapy,and 40%of them harbored occult HBV infection.The underlying mechanisms of their accelerating HBsAg seroclearance and the development of occult HBV await further investigations.Moreover,the optimal treatment strategies for dually infected patients who are seropositive for the hepatitis B e antigen must be explored.Finally,the advent of new direct-acting antiviral-based anti-HCV therapy may change the optimal therapies for patients with dual hepatitis in the near future,which warrants further clinical trials.     

Therapeutic effects of pegylated interferon plus ribavirin in chronic hepatitis C patients with occult hepatitis B virus dual infection

Background and Aim: Occult hepatitis B virus (HBV) infection is defined by the detectable serum HBV–DNA in HBV surface antigen‐negative patients. This retrospective study aims to evaluate the therapeutic effects of combined pegylated interferon (PEG–IFN) plus ribavirin (RBV) in patients with concurrent occult HBV/hepatitis C virus (HCV) dual infection. Methods: In total, 126 consecutive chronic hepatitis C (CHC) patients who received combined PEG–IFN and RBV therapy were included. Patients were divided into the occult HBV/HCV dual infection group or the HCV‐monoinfected group according to whether or not they had the detectable serum HBV–DNA. The biochemical and virological responses to combined therapy were compared between these two groups. Serum HCV‐RNA and HBV–DNA were checked before treatment, at the end of treatment as well as at 6‐ and 12‐months' follow up in the occult HBV/HCV group. Result: Six patients were seropositive for HBV–DNA and were included in the occult HBV/HCV dual infection group. There were no statistical differences in the biochemical and virological responses to combined therapy between these two groups. Undetectable serum HBV–DNA was noted at the end of the treatment and the 6‐ and 12‐months' follow up in patients with occult HBV/HCV dual infection. Conclusion: Occult HBV infection in CHC patients is rare. The biochemical and virological responses to combined PEG–IFN and RBV therapy might be similar in CHC patients with or without occult HBV infection. The serum HBV–DNA level was low in patients with occult HBV/HCV dual infection who responded to combined therapy.     

De novo hepatitis B virus infection in hepatocellular carcinoma following eradication of hepatitis C virus by interferon therapy

Epidemiological studies have revealed that hepatocellular carcinoma (HCC) is still observed in hepatitis C virus (HCV)‐positive patients with a sustained response to interferon (IFN) treatment, although a substantial decrease in the incidence of hepatocellular carcinoma (HCC) has been achieved in those patients. Why HCC develops in patients who have a complete clearance of HCV remains unclear. Here, we provided evidence of latent hepatitis B virus (HBV) infection in an initially HCV‐positive chronic hepatitis patient who developed HCC after the complete eradication of HCV by IFN therapy. Although he was initially negative for anti‐hepatitis B surface antigen (HBsAg) or circulating HBV DNA but positive for anti‐hepatitis B core antigen (anti‐HBc) in his sera, he developed HBsAg and HBV DNA during the course of the management of a series of cancers. HBV DNA was detectable in the liver tissues before HBV reactivation and the viral sequences derived from his anti‐HBc‐positive liver showed 100% homology to that from the serum after HBsAg appearance. These findings indicates that HCV‐positive individuals who are positive for anti‐HBc in the absence of HBsAg could have latent HBV infection in their liver tissues and intrahepatic HBV infection may play a pivotal role in the development of HCC after the IFN‐mediated eradication of HCV.     

Reactivation of hepatitis B virus during interferon‐free therapy with daclatasvir and asunaprevir in patient with hepatitis B virus/hepatitis C virus co‐infection

Direct‐acting antiviral agents (DAA) for hepatitis C virus (HCV) are not effective for hepatitis B virus (HBV), which may be suggestive of reactivation of anti‐HBe hepatitis during interferon (IFN)‐free DAA therapy in HBV/HCV co‐infected patients with inactive HBV. A 69‐year‐old male patient was diagnosed with chronic hepatitis due to HBV/HCV co‐infection with serum levels of alanine aminotransferase (ALT) of 94 U/L, HCV RNA of 4.2 log IU/mL and HBV DNA of 2.5 log copies/mL. HCV was thought to be responsible for the hepatitis activity because of low level of HBV core‐related antigen (3.1 log U/mL). He was treated with combination therapy of daclatasvir and asunaprevir. Serum ALT gradually increased, and reached 237 U/L on day 43 in spite of undetectable HCV RNA. Serum HBV DNA was increasing to 7.0 log copies/mL at that time. The treatment was stopped due to suspicion of drug‐induced liver injury and/or HBV reactivation. Administration of entecavir reduced HBV DNA levels, followed by improvement in ALT levels. This report proposes that close monitoring of HBV DNA during the anti‐HCV DAA therapy and the commencement of anti‐HBV therapy with nucleoside analogs after the increase of HBV DNA should be considered in patients with HBV/HCV co‐infection.     

Combination therapy with interferon-alpha and ribavirin in patients with dual hepatitis B and hepatitis C virus infection

BACKGROUND: Patients with dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection have responded poorly to interferon (IFN) monotherapy. The purpose of the present paper was to assess the effect of combined IFN-alpha and ribavirin therapy in patients infected with both hepatitis B and C. METHODS: Thirty-six patients received 3 or 5 MU IFN-alpha-2b thrice weekly and oral ribavirin (800-1200 mg/day) for 24 weeks. All patients had positive hepatitis B surface antigen, antibody to HCV, and HCV-RNA. Before treatment, one patient had positive hepatitis B e antigen. Eighteen patients had positive HBV-DNA tested by Amplicor (Cobas Amplicor Monitor, Roche Diagnostics, Branchburg, NJ, USA), with a mean HBV-DNA level of 3.1 +/- 0.9 log copies/mL. Another 72 patients with HCV infection alone served as controls. RESULTS: Adverse events led to withdrawal in three patients receiving 5 MU IFN. Based on an intent-to-treat analysis, the biochemical response and serum HCV clearance rate at the end of 48 weeks follow up was similar in patients with dual infection and HCV infection alone (56% vs 72%; and 69% vs 71%, respectively). There was no significant difference in sustained HCV clearance rate between the 3-MU group (n = 13) and the 5-MU group (n = 23; 85% vs 61%). At the end of 48 weeks follow up, two (11%) of 18 pretreatment viremic patients had negative serum HBV-DNA (<200 copies/mL), while eight of those without pretreatment viremia had re-occurrence of HBV-DNA. CONCLUSIONS: Combination therapy with IFN-alpha and ribavirin was effective in achieving sustained HCV clearance in patients with dual HBV and HCV infection, comparable to those with hepatitis C infection alone. Combination therapy using 3 MU IFN-alpha seemed as effective as 5 MU, and was well tolerated in the study population. However, large-scale control trials are necessary to clarify these findings.     

Comparing the risk of hepatitis B virus reactivation between direct‐acting antiviral therapies and interferon‐based therapies for hepatitis C

Hepatitis B virus (HBV) reactivation has been reported during antihepatitis C treatment in patients with hepatitis C virus (HCV) and HBV co‐infection. We aimed to evaluate the frequency and risk factors of HBV reactivation during anti‐HCV therapy and compared those between interferon (IFN)‐free direct‐acting antiviral (DAA) therapies and IFN‐based therapies. Three hundred and twenty‐two patients with HCV infection receiving anti‐HCV therapy were retrospectively screened. The baseline HBV infection statuses of all eligible patients and the HBV‐DNA level of all patients with current or previous HBV infection were examined at the end of treatment. In patients with baseline anti‐HBs positivity, changes in anti‐HBs titre were evaluated. Of 287 patients who met the inclusion criteria, 157 had current (n=4) or previous (n=153) HBV infection; 85 were treated with IFN‐free DAA therapies and 72 were treated with IFN‐based therapies. Six patients experienced HBV reactivation (n=2) or HBV reappearance (n=4) after IFN‐free DAA therapies, while no patient developed HBV reactivation after IFN‐based therapies. The risk factors of HBV reactivation or reappearance were DAA therapies and a reduction in anti‐HBs titre to <12 mIU mL^?1 by the end of treatment. The decline changes of anti‐HBs titre were significantly higher in patients treated with DAA therapies. Although HBV reactivation hepatitis was not observed, three of four patients with HBV reactivation or reappearance after achieving HCV eradication had viremia 8 weeks after completion of therapy. A significant proportion of patients develop HBV reactivation or reappearance without hepatitis after IFN‐free DAA therapies. Low levels of anti‐HBs and their decrease to <12 mIU mL^?1 after treatment are significant risk factors for HBV reactivation or reappearance.     

Reactivation of hepatitis viruses following immunomodulating systemic chemotherapy

Reactivation of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection following anticancer chemotherapy and immunosuppressive therapy is a well‐known complication. HBV reactivation has been reported to be associated with anti‐CD20 monoclonal antibody rituximab‐containing chemotherapy and tumor necrosis factor‐α inhibitor‐containing immunosuppressive therapy in HBV resolved patients (hepatitis B surface antigen negative and antibodies against hepatitis B core antigen positive and/or antibodies against surface antigen positive). On the other hand, HCV reactivation has been reported to be associated with liver damage or hepatic dysfunction, but fulminant hepatitis due to HCV reactivation is a rare complication. In this review, we describe the pathophysiology of the reactivation of HBV and HCV infection, as well as the clinical evidence and management of HCV reactivation.     

Low incidence of hepatitis B virus reactivation and subsequent hepatitis in patients with chronic hepatitis C receiving direct‐acting antiviral therapy

To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing interferon‐free antihepatitis C virus (HCV) therapy, we examined HBV DNA in 25 HBV co‐infected patients and 765 patients with resolved HBV infection during and after treatment with direct‐acting antiviral agents (DAAs). Among those with HCV genotype 1, asunaprevir plus daclatasvir was administered to 160 patients, sofosbuvir (SOF) plus ledipasvir to 438 patients and paritaprevir plus ombitasvir and ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus ribavirin. Three patients with an HBV DNA level ≥2000 IU/mL were treated with entecavir before anti‐HCV therapy, without reactivation of HBV. In 3 of 22 (12%) HBV surface antigen (HBsAg)‐positive patients with an HBV DNA level <2000 IU/mL, the viral load increased during treatment. However, hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV DNA level spontaneously decreased after DAA therapy. We compared anti‐HBs titres at baseline with those at post‐DAA therapy in 123 patients without HBsAg. There was no significant difference in anti‐HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in HBsAg‐negative patients treated with DAA therapy. Additionally, hepatitis did not occur in HBV‐reactivated patients with a baseline HBV DNA level <2000 IU/mL before DAA therapy.     

Current therapy for hepatitis C or D or immunodeficiency virus concurrent infection with chronic hepatitis B

Concurrent hepatitis C virus (HCV), hepatitis delta virus (HDV), or human immunodeficiency virus (HIV) infection with chronic hepatitis B virus (HBV) appears to increase the risk of progressive liver disease including liver cirrhosis and hepatocellular carcinoma. There is a 10% prevalence of HCV infection in chronic HBV or HDV infection. Serological evidence of previous exposure to HBV is found in more than 80% of HIV-positive patients in the high risk group. Notably, the most recently acquired virus tends to suppress the pre-existing virus. In chronic HBV infection acquired perinatally or in early childhood, usually HCV is dominant and may suppress or even displace HBV and HDV. Less frequently, HBV or HDV suppresses HCV. It is generally agreed that the dominant virus should be identified in order to make appropriate treatment decisions. Studies with standard interferon (IFN) to treat patients with HCV dominantly dual HBV/HCV infection have showed only limited virological response. But high dose of IFN has been demonstrated with better response rate. Combined ribavirin with standard or pegylated IFN therapy could achieve a sustained HCV clearance rate comparable with those infected with HCV alone. On the contrary, patients with HBV dominantly dual viral infection might indicate more appropriate addition of lamivudine to IFN than ribavirin. Additionally, patients with concurrent infection of HBV and HDV, IFN seems to be the only effective agent. However, the efficacy of IFN is related to the dose. High dose of IFN [9 MU tiw (thrice per week)] and longer treatment duration (at least 2 years) have been shown to achieve adequate virological response. In patients with concurrently infected HBV and HIV, anti-HBV therapy should be considered for all patients with evidence of liver disease, irrespective of the CD4 cell count. In patients not requiring antiretroviral therapy, HBV therapy should be preferentially based on IFN, adefovir, or telbivudine. In contrast, in patients with CD4 cell counts <350 cells/μl or those already on antiretroviral therapy, agents with double anti-HBV and anti-HIV activity are preferred. At present, the evidence of therapeutic efficacy is not sufficient to make a recommendation in treating patients with dual HBV/HCV or HBV/HDV or HBV/HIV infection. Further studies of the well-designed, larger scale are needed to elucidate the role of different regimens or combination in the treatment of dual viral infection.     

MiR-122 in hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the most common causes of chronic liver diseases and hepatocelluar carcinomas. Over the past few years, the liver-enriched microRNA-122 (miR-122) has been shown to differentially regulate viral replication of HBV and HCV. It is notable that the level of miR-122 is positively and negatively regulated by HCV and HBV, respectively. Consistent with the well-documented phenomenon that miR-122 promotes HCV accumulation, inhibition of miR-122 has been shown as an effective therapy for the treatment of HCV infection in both chimpanzees and humans. On the other hand, miR-122 is also known to block HBV replication, and HBV has recently been shown to inhibit miR-122 expression; such a reciprocal inhibition between miR-122 and HBV suggests an intriguing possibility that miR-122 replacement may represent a potential therapy for treatment of HBV infection. As HBV and HCV have shared transmission routes, dual infection is not an uncommon scenario, which is associated with more advanced liver disease than either HBV or HCV mono-infection. Thus, there is a clear need to further understand the interaction between HBV and HCV and to delineate the role of miR-122 in HBV/HCV dual infection in order to devise effective therapy. This review summarizes the current understanding of HBV/HCV dual infection, focusing on the pathobiological role and therapeutic potential of miR-122.     

Impact of acute hepatitis C virus superinfection in patients with chronic hepatitis B virus infection

BACKGROUND & AIMS: Superinfection in patients with chronic hepatitis B virus (HBV) infection is not uncommon. Acute hepatitis delta virus (HDV) superinfection is associated with severe and/or progressive liver disease. The natural course following acute hepatitis C virus (HCV) superinfection has not been well studied. The aim of this study was to investigate the impact of acute HCV superinfection. METHODS: The clinical features during acute phase and long-term outcomes of acute HCV superinfection were studied and compared with a cohort of acute HDV superinfection and a matched control group of active chronic hepatitis B. RESULTS: Acute HCV superinfection typically occurs as acute icteric hepatitis. The severity is similar to acute HDV superinfection in that hepatic decompensation developed in 34% of patients, hepatitis failure occurred in 11%, and 10% died. During a follow-up period of 1-21 years, patients with acute HCV superinfection had a significantly higher cumulated incidence of cirrhosis (48% at 10 years) and hepatocellular carcinoma (14% at 10 years, 21% at 15 years, and 32% at 20 years) than acute HDV superinfection or active chronic hepatitis B. Hepatitis B surface antigen (HBsAg) seroclearance occurred earlier in HCV superinfected patients. Continuing hepatitis after HBsAg seroclearance was observed only in HCV superinfected patients. CONCLUSIONS: Acute HCV superinfection in patients with chronic HBV infection is clinically severe during its acute phase. The long-term prognosis following acute HCV superinfection is much worse than that following HDV superinfection or active hepatitis B in terms of continuing hepatitis activity after HBsAg loss and the development of cirrhosis or hepatocellular carcinoma.     

Hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) share common mode of transmission and both are able to induce a chronic infection. Dual HBV/HCV chronic coinfection is a fairly frequent occurrence, especially in high endemic areas and among individuals at high risk of parenterally transmitted infections. The intracellular interplay between HBV and HCV has not yet been sufficiently clarified, also due to the lack of a proper in vitro cellular model. Longitudinal evaluation of serum HBV DNA and HCV RNA amounts has revealed that complex virological profiles may be present in coinfected patients. Dual HBV/HCV infection has been associated to a severe course of the liver disease and to a high risk of developing hepatocellular carcinoma. Despite the clinical importance, solid evidence and clear guidelines for treatment of this special population are still lacking. This review summarizes the available data on the virological and clinical features as well as the therapeutic options of the dual HBV/HCV infection, and highlights the aspects that need to be better clarified.     

Isolated antibodies against the core antigen of hepatitis B virus in HIV-infected patients

The aim of this study was to describe the frequency and significance of isolated antibodies against the hepatitis B virus (HBV) core antigen (HBc) in 2185 HIV-infected patients of the Aquitaine Cohort. Antibodies against HBc were found in 372 subjects (17%). Patients with isolated anti-HBc antibodies were more frequently coinfected with hepatitis C virus (HCV) (58.2%) than those who were anti-HB surface (HBs) antibody positive (22.9%, P<0.001) and those who were dually reactive anti-HBs/anti-HBc antibody positive (27.3%, P<0.001). These results suggest interactions between HBV and HCV. As observed in patients not infected with HIV, the "anti-HBc-alone" serological profile could reflect essentially late immunity with undetectable anti-HBs antibodies. However, an occult HBV infection cannot be ruled out.     

Incidence of hepatitis virus infection and severe liver dysfunction in patients receiving chemotherapy for hematologic malignancies

Hepatitis virus infection through virus reactivation has a high risk of mortality in patients with hematological malignancies receiving chemotherapy. We examined the incidence of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and severe liver dysfunction (alanine aminotransferase >ten times the normal upper limit and total bilirubin >5 mg/dl) during chemotherapy in 268 patients with hematological malignancies. Eight patients (3.0%) were infected with HBV and 22 patients (8.2%) were infected with HCV. One patient (0.4%) was infected with both HBV and HCV. HBV- or HCV-infected patients showed severe liver dysfunction at a significantly higher incidence than non-infected patients (11/31 (35.5%) vs. 0/237 (0%), p<0.0001). Furthermore, the incidence of severe liver dysfunction in HBV-infected patients was significantly higher than in HCV-infected patients (6/8 (75.0%) vs. 4/22 (18.2%), p<0.01). Three of eight HBV-infected patients were initially negative for hepatitis B surface antigen (HBsAg) by latex agglutination and became positive for HBsAg during chemotherapy. Furthermore, all three patients developed severe liver dysfunction and two developed fatal fulminant hepatitis. From an examination of the original stock of serum samples before chemotherapy, two patients were found to be positive for HBV-DNA by polymerase chain reaction (PCR). Although post-transfusion HBV infection was suspected in the one remaining patient, the cause of HBV infection could not be clarified due to the impossibility of examination in blood donors. Since HBV-infected patients develop severe liver dysfunction at a higher incidence than either patients not infected with virus or HCV-infected patients before chemotherapy for hematological malignancies, it is recommended that HBV-DNA should be tested by PCR to detect HBV marker-negative carriers and liver function tests should be carefully monitored.     

Ribavirin and interferon is effective for hepatitis C virus clearance in hepatitis B and C dually infected patients

Ribavirin and interferon (IFN) are an effective treatment in 30% to 60% of patients with chronic hepatitis C. Whether they are also effective in dually infected patients with hepatitis B and C is unknown. Twenty-four patients with chronic hepatitis seropositive for both hepatitis B surface antigen and antibody to HCV received ribavirin 1,200 mg daily for 6 months, together with 6 million units (MU) IFN-alpha 2a thrice weekly for 12 weeks and then 3 MU for another 12 weeks. Serum HCV RNA was positive in 21 patients (group I, serum HBV DNA positive in 17 patients) and negative in 3 patients (group II, all HBV DNA positive) by Amplicor (Cobas Amplicor Monitor, Roche Diagnostics, Branchburg, NJ). Serum alanine aminotransferase (ALT), HCV RNA, and hepatitis B virus (HBV) DNA were monitored regularly for 12 months. Another 30 patients with chronic hepatitis C alone receiving the same regimen, served as controls. The serum HCV clearance rate in group I patients (43%) was comparable with that in controls (60%, P =.63) 24 weeks posttreatment. The serum ALT normalization rate in group I and group II patients was 43% and 0%, respectively, 24 weeks posttreatment. After treatment, resurgence of HBV and HCV was encountered in 4 group I patients and 1 group II patient, respectively. In conclusion, in hepatitis B and C dually infected patients, combination of IFN with ribavirin can achieve a sustained HCV clearance rate comparable with hepatitis C alone. In dually infected patients, the treatment may alter the dominant, ruling hepatitis virus.     

Understanding the pathogenesis and management of hepatitis B/HIV and hepatitis B/hepatitis C virus coinfection

The approach to the hepatitis B virus (HBV)-infected patient who is also infected with HIV or hepatitis C virus (HCV) is very different from the approach to the patient with only one virus infection. HBV/HIV coinfection is common. Agents that have dual activity against HBV and HIV should be considered as treatment of choice in combination regimens in HBV/HIV-coinfected patients beginning antiretroviral therapy. In HBV/HCV coinfection HCV usually tends to predominate over HBV. More investigation is needed into the mechanisms by which viral pathogenesis is altered and the optimal treatment modalities for coinfected patients.     

Clinical and histological impact of previous hepatitis B virus infection in patients with chronic hepatitis C

Background: Recent reports suggest that hepatitis C virus (HCV) carriers with serological markers of prior hepatitis B virus (HBV) infection have more advanced liver fibrosis, irrespective of HBV‐DNA detection. Aims: We sought to assess the prevalence and impact of previous HBV infection in patients with HCV chronic infection. Methods: This cross‐sectional study included hepatitis B surface antigen‐ and human immunodeficiency virus‐negative subjects with positive HCV‐RNA. All patients had prior parenteral exposure as the probable source of HCV infection. Serum samples were tested for HBV‐DNA using a commercial assay. The METAVIR system was used for histological analysis. Results: One‐hundred and eleven patients were evaluated. Thirty‐one out of 111 patients (28%) tested positive for antihepatitis B core antigen (anti‐HBc). HBV‐DNA was not detected in any sample. Anti‐HBc‐positive patients showed higher histological grading, staging and a higher fibrosis progression rate. By multivariate analysis, anti‐HBc‐positivity was predictive of moderate to severe activity [odds ratio (OR)=3.532; P=0.032] and significant hepatic fibrosis (OR=3.364; P=0.017). After approximately 20 years of infection, advanced liver fibrosis (F3/F4) can be expected in 13% of anti‐HBc‐negative subjects who acquired HCV before the age of 30 and in 57% of those anti‐HBc‐positive patients who were infected by HCV after 30 years of age (P<0.001). Conclusion: Previous HBV infection is common among HCV carriers and may exert a negative impact on the natural history of HCV infection, independently of the presence of significant HBV replication.