Responsiveness to interferon alpha treatment in patients with chronic hepatitis C coinfected with hepatitis G virus

BACKGROUND/AIMS: Patients with chronic hepatitis C are often coinfected with the new identified Flaviviridae-like agent, termed hepatitis G virus (HGV). The aim of the study was to investigate the responsiveness of hepatitis G virus to interferon alpha and to evaluate whether a hepatitis G virus coinfection negatively influences the outcome of treatment in chronic hepatitis C. METHODS: One hundred and fifteen patients with histologically proven chronic hepatitis C were treated with interferon alpha and investigated for the presence of hepatitis G virus coinfection by nested polymerase chain reaction with primers from the helicase region of hepatitis G virus. All patients received at least 3 MU (range 3-6) interferon alpha thrice weekly for at least 6 months (mean 8, range 6-12). Polymerase chain reaction products of seven pre- and post-treatment hepatitis G virus positive patients were directly sequenced for identification of sequence variability during the follow-up. RESULTS: Eighteen (16%) patients were coinfected with hepatitis G virus. Although nine (50%) of these patients became HGV RNA negative during interferon alpha therapy, only three patients (17%) remained HGV RNA negative at the end of follow-up (mean 24 months). The rate of sustained response of chronic hepatitis C was not significantly different between patients with hepatitis C virus infection and HCV/HGV coinfection (19% vs 28%). Severity of liver disease as determined by alanine aminotransferase levels, histology and hepatitis C virus viremia was not significantly different in patients with hepatitis C virus or HCV/HGV coinfection. Sequence analysis of the helicase region revealed that our isolates all belonged to the hepatitis G virus and not to the GBV-C like genotype. No amino acid exchanges during the observation period of up to 48 months were observed, indicating that this region is highly conserved. CONCLUSIONS: The responsiveness of hepatitis G virus to interferon alpha in chronic HCV/HGV coinfected patients is similar to that observed in chronic hepatitis C. Hepatitis G virus coinfection seems not to interfere with the efficacy of interferon alpha treatment in patients with chronic hepatitis C.     

Hepatitis C and G co-infection: response to interferon therapy and quantitative changes in serum HGV-RNA

Hepatitis G virus (HGV), a positive sense RNA virus, is distantly related to hepatitis C virus (HCV): its genetic organization and identity are consistent with the Flaviviridae family. Coinfection with HGV occurs in 10% to 20% of HCV-infected subjects. These similarities raise two theoretical questions. First, could HGV coinfection play any role in the response of HCV to antiviral therapy and second, would this coinfected population have changes in serum HGV-RNA induced by interferon. To address these questions, 98 patients with documented chronic HCV underwent interferon therapy (3 million units three times a week) for 6 months. Response to therapy was categorized using standard biochemical criteria. Changes in HGV-RNA levels were evaluated before, during, and after interferon therapy by a quantitative branched DNA amplification research-based assay. Eleven of 98 (11%) patients with HCV infection had detectable serum HGV-RNA. There was no difference between the groups (HGV+ vs. HGV-) when baseline alanine aminotransferase (ALT) values, HCV-RNA levels, HCV genotype, histological severity, or other demographic features were analyzed. Interferon response was similar in both groups and HGV was not associated with outcome following therapy. Antiviral therapy appeared to induce a reduction in HGV-RNA load in five of nine patients coinfected with HCV serially tested. In two patients, the fall in serum HGV-RNA correlated with biochemical response, independent of changes in HCV-RNA. These observations indicate that a larger study of an HGV population is required to more clearly define the relationship between HCV and HGV coinfection and their response to antiviral therapy.     

Efficacy of ribavirin plus interferon alpha on viraemia of GB virus-C/hepatitis G virus: comparison with interferon alpha alone

We investigated the efficacy of ribavirin plus interferon (IFN) alpha on GB virus-C (GBV-C)/hepatitis G virus (HGV) viraemia and compared it with that of interferon alpha alone in patients coinfected with hepatitis C virus (HCV) and GBV-C/HGV. Serum HCV and GBV-C/HGV-RNA were studied in eight patients with HCV and GBV-C/HGV coinfection, five received IFN alpha and three received oral ribavirin plus IFN alpha. Mean serum GBV-C/HGV titre at the end of therapy was significantly lower than the titre just before therapy and patients with lower pretreatment titre had a better sustained response rate. Sustained virological response of GBV-C/HGV to IFN alpha alone and ribavirin plus IFN alpha at the end of follow up was observed in one each, respectively. Thus, GBV-C/HGV in patients with HCV and GBV-C/HGV coinfection does respond to IFN alpha and ribavirin plus IFN alpha may not induce a higher sustained response.     

Hepatitis G and C viruses respond to interferon-alpha with different virologic kinetics

The aim of this work was to specify the time course of response to interferon (IFN) of hepatitis G virus (HGV) and hepatitis C virus (HCV) in coinfected individuals. A group of 33 patients, undergoing 12 months of IFN therapy for chronic hepatitis C, was screened for the presence of both HGV and HCV RNAs to select seven coinfected patients. Spontaneous recovery from HGV infection was excluded through the detection of antibodies to the envelope-2 protein of HGV and HCV isolates were genotyped. Within three months of treatment, we found that HGV RNA was transiently cleared in 6/7 patients, but the rate of long-term favorable response was very low (1/7). In addition, considering the same individuals separately, it was shown that HGV and HCV responded to IFN with different kinetics in 5/7 patients. Taken together, these results underscore the importance of the virological basis of the resistance to IFN treatment.     

Quantitation of hepatitis G and C viruses in the liver: evidence that hepatitis G virus is not hepatotropic

Hepatitis G virus (HGV) is prevalent in patients with chronic liver disease and has been previously detected in liver specimens. However, it is unknown whether the virus is replicating in the liver or is simply a contaminant from serum. We sought to determine whether HGV was hepatotropic and to determine whether coinfection with HGV and hepatitis C virus (HCV) influenced the level of either virus. Virus was quantitated using branched DNA (bDNA) assay for both HGV and HCV in the liver explants and pretransplant serum samples from 30 transplant recipients: Group I, HGV/HCV coinfection (n = 10); group II, HCV infection alone, (n = 8); group III, HGV alone (n = 12). In patients with coinfection HCV (RNA) titers in liver were consistently higher than those for HGV RNA (median 1.13 x 10(8) and 360,000 Eq/g respectively, P < .01). The ratio of liver/serum viral RNA was significantly higher for HCV than for HGV (median 129 and 0.3 respectively, P < .01). Levels of HCV RNA were similar in patients with HCV infection alone versus those with HGV/HCV coinfection (median; liver = 1.15 x 10(7) vs. 1.13 x 10(8) Eq/g, serum = 500,000 vs. 200,000 Eq/mL) and levels of HGV RNA in liver and serum were similar in patients with HGV infection alone compared to those with HGV/HCV coinfection (median; liver = 1.2 x 10(6) vs. 4.0 x 10(5) Eq/g, serum = 4.5 x 106 vs. 2.6 x 10(6) Eq/mL). Levels of either virus appeared unaffected by the presence of an additional virus. The high ratio of HCV RNA levels in liver compared to serum is consistent with its known hepatotropism, but this pattern was not observed for HGV. The median liver/serum ratio of HGV RNA was less than unity, a finding consistent with serum contamination of liver tissue. Thus we conclude that the liver is not the main site of HGV replication.     

A multicenter controlled, randomized, open trial of interferon alpha2b treatment of anti-human immunodeficiency virus-negative hemophilic patients with chronic hepatitis C. Hepatitis Study Group of the Association of Italian Hemophilia Centers

There is limited information about the long-term efficacy of prolonged therapy (more than 6 months) with interferon alpha in hemophilic patients with chronic hepatitis C who are not coinfected with the human immunodeficiency virus (HIV-1). One hundred and seven hemophiliacs were randomly assigned to 3 million U of interferon alpha2b three times weekly for 12 months or no therapy. The patients were followed up for at least 12 months posttreatment. Response was assessed by both serial alanine aminotransferase (ALT) levels and hepatitis C virus (HCV)-RNA measured by reverse transcribed polymerase chain reaction (RT-PCR) method. Before treatment, serum levels of HCV-RNA were measured quantitatively by second-generation branched-DNA assay and the HCV genotype was determined by RT-PCR. Serum HGV-RNA, a marker of infection with the hepatitis G virus, was also measured by RT-PCR. Normalization of ALT was sustained and serum HCV-RNA was cleared in 6 of 45 treated patients, compared with none of the 50 untreated controls (13% v 0% P < .01). Low pretreatment viremia was the only feature that was associated with an increased likelihood of sustained response (P < .01). This study shows that multitransfused hemophiliacs with chronic hepatitis C not coinfected with HIV-1 respond at low rates to prolonged interferon therapy.     

Serum hepatitis G virus RNA in patients with chronic viral hepatitis

OBJECTIVES: The hepatitis G virus (HGV) is a newly described flavivirus that affects a high proportion of patients with chronic viral hepatitis: our objective was to determine what role HGV might play in the course of disease. METHODS: We evaluated stored serum samples from 108 patients with chronic hepatitis B and 99 patients with chronic hepatitis C who participated in trials of alpha-interferon or ribavirin for the presence of hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA by branched DNA and for the presence of HGV RNA by polymerase chain reaction (PCR), using primers from the NS5 region of the genome. RESULTS: Initially, 20 (19%) patients with hepatitis B and 11 (11%) with hepatitis C had HGV RNA in their serum. Patients with and without HGV infection were similar with regard to clinical features, laboratory tests, and hepatic histology. HGV RNA levels fell during interferon therapy and became undetectable in those receiving the highest doses; however, HGV RNA levels returned to pretreatment values when therapy was stopped. With ribavirin therapy, HGV RNA levels did not change. Two- to 12-yr follow-up serum samples were available from 17 initially HGV RNA-positive patients, of whom only 10 (59%) were still positive. CONCLUSIONS: HGV infection is common among patients with chronic hepatitis B and C but has little effect on the short-term course of disease or response to therapy. HGV RNA levels are suppressed but not eradicated by alpha-interferon and are unaffected by ribavirin treatment. Spontaneous loss of HGV RNA occurs over time in a proportion of patients.     

Hepatitis G virus infection in hemodialysis patients and the effects of interferon treatment

OBJECTIVE: To characterize the nature of hepatitis G virus (HGV) infections in hemodialysis patients and to determine the responsiveness of HGV to antiviral therapy in these patients. METHODS: HGV, a recently identified flavivirus, is associated with non-A-E viral hepatitis infections. We studied HGV infections in hepatitis C virus (HCV)-infected hemodialysis patients over a 1-yr period, using two independent PCR assays and nucleic acid sequencing. Thirty-four of 63 study patients were treated with interferon. RESULTS: We observed a 27% prevalence (17/63 patients) and a 4% annual incidence of HGV infections in the study population. HGV was not detected in any of the 10 HGV-infected patients immediately after interferon therapy. Although seven of these 10 patients developed HGV relapses, three had long-term responses. The interferon responsiveness of HGV and HCV appeared to be unrelated. In contrast, all seven untreated HGV-infected patients remained viremic. Sequence analyses of the different HGV isolates revealed only very limited genetic variability in the polymerase chain reaction-amplified regions of HGV during 1 yr of observation. CONCLUSIONS: Our data suggest that HCV-infected hemodialysis patients are at substantial risk of acquiring HGV infection and that HGV infections are prevalent in this population. In addition, HGV infections become chronic but are responsive to interferon treatment.     

GB virus-C/hepatitis G virus infection in an area endemic for viral hepatitis, chronic liver disease, and liver cancer

BACKGROUND & AIMS: GB virus-C/hepatitis G virus (GBV-C/HGV) is a newly identified flavivirus, and little is known about its clinical significance. GBV-C/HGV was investigated in different populations, and its coinfection was investigated in patients with liver disease in Taiwan where hepatitis B and C are endemic. METHODS: Viral RNA was studied in 70 high-risk individuals, 20 patients with chronic non-B, non-C hepatitis, 13 with non-A-E fulminant hepatitis, 100 with asymptomatic hepatitis B surface antigen carriage, 120 with hepatitis B surface antigen-positive chronic liver disease and hepatocellular carcinoma, 100 patients with chronic hepatitis C, and 100 healthy adults. RESULTS: GBV-C/HGV infection was more frequent in high-risk groups (15%-30%) and hepatitis C virus carriers (10%) than in healthy adults (1%) and hepatitis B virus carriers (3.2%). Eighty-three percent of those infected had undergone blood transfusions previously. The prevalence in hepatitis B virus carriers increased with the severity of liver disease, being 1% in asymptomatic carriers and 10% in hepatocellular carcinoma. In chronic hepatitis C, clinical and virological data were comparable between those with and without coinfection. CONCLUSIONS: In Taiwan, GBV-C/HGV infection is common in high-risk groups, and its coinfection seems to not aggravate the course of chronic hepatitis B or C.     

Clinical implications of GBV-C/HGV infection in patients with "HCV-related" chronic hepatitis

BACKGROUND/AIMS: To evaluate the clinical, biochemical and histological implications of a concomitant HGV infection in "HCV-related" chronic liver disease. METHODS: Eighty-three HCV-RNA positive patients with chronic liver disease were tested for GBV-C/HGV coinfection by heminested PCR. RESULTS: Twenty-two (26.5%) patients were found to be positive for GBV-C/HGV RNA. GBV-C/HGV+ patients differed significantly from GBV-C/HGV- ones for younger age, higher frequency of history of drug addiction, which in turn might favor coinfection with interferon-sensitive HCV genotypes (3a), and increased probability of long-term response to interferon. GBV-C/HGV infection appears to have no responsibility for specific aspects of HCV infection such as biochemical or histological cholestatic features, lymphoid follicles, symptomatic cryoglobulinemia or presence of serum autoantibodies, including LKM1. It does not worsen the HCV-related disease (ALT levels and histological activity) and does not significantly interfere with HCV infection, as explored by the number of hepatocytes positive for HCV antigens. The amount of steatosis (mean score) was shown to be higher in GBV-C/HGV+ patients. A virological follow up was performed in 17 interferon-treated GBV-C/HGV+ patients On the whole, GBV-C/HGV seems to be as sensitive to IFN treatment as HCV, but recurrence after withdrawal is more frequent. In spite of this, ALT levels often remain normal after treatment withdrawal. CONCLUSIONS: The present data suggest that GBV-C/HGV infection, apart from more marked liver steatosis, does not modify the overall picture of chronic hepatitis due to HCV infection.     

Hepatitis G virus co-infection in liver transplantation recipients with chronic hepatitis C and nonviral chronic liver disease

Hepatitis G virus (HGV) is a newly described RNA virus that is parenterally transmitted and has been found frequently in patients with chronic hepatitis C infection. To determine the impact of hepatitis G virus co-infection on morbidity and mortality following liver transplantation, we measured HGV RNA by polymerase chain reaction in pre and posttransplantation sera from a cohort of patients transplanted for chronic hepatitis C and a control group of patients transplanted for nonviral causes who were negative for hepatitis C virus (HCV) RNA in serum. The overall prevalence rate of HGV RNA in transplanted patients with chronic hepatitis C was 20.7%. HGV infection was present before transplantation in 13% while it appeared to have been acquired at the time of transplantation in 7.4%. Mean serum alanine aminotransferase activity, hepatic histological activity, and patient and graft survival were similar between HGV-positive and HGV-negative patients. The prevalence rate of HGV RNA in transplanted controls was 64% (P < .01) with a significantly higher rate of acquisition of HGV infection following transplantation (53%, P < .001) when compared with patients with chronic hepatitis C. Mean serum alanine aminotransferase activity was significantly lower in the control patients with HGV infection alone following transplantation than in patients co-infected with hepatitis C (37 +/- 9 vs. 70 +/- 33 U/L, P < .01). Thus, HGV is frequently found in transplantation patients co-infected with hepatitis C although it appears to have minimal clinical impact. In patients transplanted for nonviral causes of end-stage liver disease, a high rate of hepatitis G acquisition at the time of transplantation may occur but does not appear to predispose to chronic hepatitis.     

Hepatitis G virus in the general population and in patients on hemodialysis

To determine the routes of transmission of hepatitis G virus (HGV) and the relationship between HGV and hepatitis C virus (HCV) infections, we tested for HGV RNA by polymerase chain reaction and antibody to HCV (anti-HCV) in 494 hemodialysis patients, 638 inhabitants of two HCV endemic areas, and in 400 blood donors in Japan. HGV RNA was detected in 6.9% of hemodialysis patients, in 1.4% of inhabitants, and in 0.8% of donors, and anti-HCV was detected in 39.3%, 12.4%, and 1.8%, respectively. Of HGV RNA-positive hemodialysis patients, and HGV RNA-positive inhabitants, 64.7% and 11.1%, respectively, had been given blood transfusions. The prevalences of HGV RNA and anti-HCV significantly increased with the duration of hemodialysis. Of all HGV RNA positives, 74.4% were coinfected with HCV and subjects with HGV RNA alone had normal liver function. In conclusion, HGV is transmitted by blood transfusion and within the hemodialysis unit itself. HGV does not seem to injure hepatocytes.     

Local intralesional therapy with rhGM-CSF for a large genital ulcer in Beh?et''s disease

Infection with the hepatitis G virus (HGV), as indicated by the presence of HGV ribonucleic acid, was sought in 57 children with chronic hepatitis C virus infection. HGV infection was found in 2 children (3.5%), or 14% of the babies whose mothers were former drug abusers. Maternal drug abuse is an important risk factor for hepatitis G and C virus coinfection in children in our area.     

Hepatitis G virus infection in hemodialysis patients

The increased risk of hemodialysis patients for infections sustained by hepatitis viruses is likely to extend to a newly discovered parenterally transmitted virus, HGBV-C/HGV, able to cause acute and chronic hepatitis. The aim of this study was to assess the prevalence and clinical relevance of this infection in Italian hemodialysis patients. Nineteen of 100 patients (19%) on maintenance hemodialysis were viremic for HGBV-C/HGV, and all of them were infected with a HGV-like genotype. Eight of these patients were coinfected by hepatitis B or hepatitis C viruses. A clinical picture of chronic hepatitis was not appreciable in patients with isolated HGV infection and the presence of HGV did not appear to modify the clinical course of hepatitis B and hepatitis C infections.     

Mutations in the nonstructural 5A region of hepatitis C virus and response of chronic hepatitis C to interferon alfa

BACKGROUND & AIMS: Mutations in hepatitis C virus (HCV) nonstructural protein 5A (NS5A) may correlate with response to interferon in Japanese patients with chronic hepatitis C. The aim of this study was to examine whether these findings could be expanded to European patients infected with genotypes associated to low (1b) or high (3a) response rates. METHODS: Pretreatment serum samples of 66 patients with chronic HCV infection, 48 infected with genotype 1b and 18 with 3a, were analyzed. RESULTS: Among patients infected with genotype 3a, 1 of 7 long-term responders and none of 11 nonresponders showed NS5A amino acid mutations. Among patients infected with genotype 1b, all 7 long-term responders, but also 27 of 41 nonresponders, showed NS5A mutations. There was no correlation between number of mutations and response to therapy. In 10 patients, sequences obtained before and after treatment were compared and failed to show any change. Serum HCV RNA levels did not differ between patients with and without mutations in NS5A sequence. CONCLUSIONS: No significant correlation was found in patients infected with genotypes 1b or 3a between NS5A sequence and response to interferon alfa. NS5A mutations do not correlate with viral load. Changes in this region were not found during interferon alfa treatment.