Serum Hepatitis C Virus Research Articles

Incidence and risk factors of HCV and HIV infections in a cohort of intravenous drug users in the North and East of France.

In order to evaluate the incidence and risk factors of infection by hepatitis C virus (HCV) among injecting drug users (IDUs), we conducted a prospective cohort study of HCV- and human immunodeficiency virus (HIV)-negative IDUs in the North and East of France. A total of 231 HCV and HIV IDUs who had injected drugs at least once in their lifetime were followed up every 3 months over a 12-month period. Serum anti-HCV and anti-HIV were tested at inclusion in the study and at the end of the follow-up. Data on injecting practices were collected at inclusion and at each visit. Of the 231 participants included, 165 (71.4%) underwent a final HCV and HIV serum test. The incidence was nil for HIV infection and 9/100 person-years (95% CI 4.6-13.4) for HCV infection. In a multivariable analysis, we found that syringe and cotton sharing were the only independent predictive factors of HCV seroconversion.

Simultaneous runs of the Bayer VERSANT HIV-1 version 3.0 and HCV bDNA version 3.0 quantitative assays on the system 340 platform provide reliable quantitation and improved work flow.

Branched DNA (bDNA) assays to quantify human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) consist of three distinct steps, including sample processing, hybridization, and detection, and utilize the System 340 platform for plate incubation and washing. Sample processing differs: HIV-1 from 1 ml of plasma is concentrated by high-speed centrifugation, whereas HCV plasma or serum samples are used without concentration. The first step of hybridization involves viral lysis at 63 degrees C: HIV-1 is performed in a heat block, whereas HCV is performed in System 340. The remaining hybridization and detection steps are similar for HIV-1 and HCV and executed on System 340. In the present study, the HIV-1 bDNA assay was adapted for viral lysis in the System 340 platform. The adaptation, test method 2, includes a 20-s vortex of concentrated viral pellet and lysis working solution, transfer of viral lysate to the 96-well capture plate, and transfer to System 340 programmed for HCV assay specifications. With test method 2, specificity and quantification were within assay specifications. HCV bDNA methodology remains unchanged. Hence, an HIV-1 and an HCV bDNA can be run simultaneously on System 340. With simultaneous testing, laboratories can run full plates, as well as combinations of full and partial plates. Also, simultaneous HIV-1 and HCV bDNA permits labor consolidation and improved workflow while maintaining multitasking and rapid patient result turnaround.

Hepatocyte Growth Factor and Viral Load Variations in HD Session, Comparison with Molecular Absorbent Recirculating System (MARS) Therapy

A decrease in hepatitis C viral load in HD patients along HD sessions has been described. It has also been proposed that hepatocyte growth factor (HGF) stimulation by HD could have some protective effect in hepatitis C virus (HCV) liver disease outcome.Aims: (i) Measurement of HCV viral load variation and quantitation of HGF stimulation in CKD patients (HCV+ and HCV–) on HD, along the HD session. (ii) Study whether albumin HD (MARS) decreases HCV viral load and stimulates HGF, compared to HD sessions.Methods: We performed two MARS and two HD sessions in vitro by using an extracorporeal circuit with blood bag contaminated with HCV serum with a known HCV viral load. (We used only a single blood bag for each testing.) In vivo we performed three MARS sessions. The total number of treatments was 6 in 2 patients (3 treatments each) and one HD session in 2 HCV+ patients and 5 HCV– patients (included in HD program in our center), taking samples at the start of the following HD session, to compare the results with those obtained in vitro. We took samples at the beginning, middle, and at the end of MARS sessions in vivo and in vitro and starting (15 min) and at the end and before starting the following HD session in vivo. (The interval between 2 HD sessions in HCV+ patients was 2 days.) We determined HCV viral load using Amplicor (Roche) and HGF using ELISA (R&D System).Results: We found a decrease of viral load in vitro and in vivo both by MARS and HD. HD in vitro: ×decrease HCV viral load, 54.67%. HD in vitro × decrease viral load 30.6% × HD in vivo. We found a decrease of 30% in viral load, remaining 27.9% lower at the start of the following session. MARS in vitro: ×viral load decrease 3% (1 session in 2 experiments). MARS in vivo: ×viral load decrease of 44.5% (6 sessions in 2 patients). We did not find HCV viral load in ultrafiltrate or albumin from MARS procedure. Analyzing HGF stimulation we found the following: MARS in vitro: start, 1001; 15 min, 1537; final, 1981 HD in vitro: start, 476; 15 min, 677; final, 1236 HD in vivo: start, 2808.57; ×15 min, >8000; final, 2605.28; ×start the following session, 2299.5 MARS in vivo: HGF starting (first session, 4633; second session, 4390; third session, 4775); at 4 h (first session, 5443; second session, 4167; third session, 5178); final (first session, 4477; second session, 6167; third session, 5078). Conclusions: MARS and HD sessions decreased HCV viral load and stimulated HGF both in vitro and in vivo. It is necessary to confirm these results because it could offer protective effect for HCV chronic liver disease outcome. HD seems to be the best option for patients with HCV hepatopathy. On the other hand, patients with liver disease who need to be treated with MARS could obtain not only a good clearance of toxin binding to albumin, but also the positive effects described.

Antigenic relevance of F protein in chronic hepatitis C virus infection.

The hepatitis C virus (HCV) F protein is a recently described, frameshift product of HCV core encoding sequence of genotype 1a. Its function and antigenic properties are unknown. Using enzyme-linked immunosorbent assay, we assessed the prevalence of anti-F antibodies in 154 patients chronically infected with HCV, 65 patients with other liver diseases, and 121 healthy controls. For this purpose, we expressed a highly purified HCV F recombinant protein from HCV genotype 1a in Escherichia coli. Because the F protein shares the 10 first amino acids with the core protein, the anti-HCV F response was also assessed by a F recombinant protein deleted of its 10 first amino acids [Delta(1-10)-F]. Ninety-six (62%) of the 154 HCV serum samples reacted with the complete F recombinant protein, whereas 39 (25%) showed a weaker anti-Delta(1-10)F reactivity and 150 (97%) had anti-core antibodies. No reactivity against F, Delta(1-10)F, or core was detected in any of the controls. To exclude a potential cross-reaction of anti-F antibodies with anti-core antibodies, a specific enzyme-linked immunosorbent assay was performed for anti-core antibodies. The specificity of anti-F antibodies was confirmed using an F synthetic peptide. The prevalence of anti-F antibodies did not correlate with HCV RNA serum level, genotype, or stage of liver disease. Sequence analysis from 8 anti-F-positive and 5 anti-F-negative serum samples did not reveal any particular difference potentially accounting for their respective anti-F responses. In conclusion, the F protein elicits specific antibodies in 62% of individuals chronically infected with HCV; such anti-F response does not seem to be affected by the F sequence heterogeneity.

Hepatitis C virus genotypes and hepatic fibrosis regulate 24‐h decline of serum hepatitis C virus RNA during interferon therapy in patients with chronic hepatitis C

Recently, hepatitis C virus (HCV) dynamics during interferon (IFN) therapy have been studied in detail. We examined factors that regulate the viral kinetics and the relationship between the viral kinetics and clinical effect of IFN therapy. Eighty-eight patients with chronic hepatitis C entered this study. All patients had been treated with 3 MU of IFN-beta twice a day for the first 2-4 weeks, then IFN-alpha for the next 20-22 weeks (three injections per week). The levels of serum HCV RNA were determined by Amplicor HCV Monitor version 1.0, before and 24 h after the first injection of IFN; then the decline of HCV was calculated. Liver inflammation and fibrosis were scored as 0 (none), 1 (mild), 2 (moderate) or 3 (severe) using biopsy specimens. The decline of serum HCV RNA was 1.42 +/- 0.65 log copies/mL in genotype 1b and 1.83 +/- 0.72 in genotype 2a or 2b (P < 0.01). By a logistic regression model, genotype (1b, 2a or 2b) and hepatic fibrosis (0 or 1, 2 or 3) associated with 24-h decline of serum HCV RNA, independently. As the predictor of IFN therapy, the decline of serum HCV RNA and serum HCV RNA levels before IFN therapy were the independent significant factors (P < 0.001). The decline of serum HCV RNA during the first 24 h of IFN therapy was regulated by genotypes and hepatic fibrosis. The decline of serum HCV RNA and initial HCV load were independent factors that can be the predictor of the subsequent sustained viral response to IFN therapy.

Detection of hepatitis C virus (HCV) RNA in normal cervical smears of HCV-seropositive patients.

The presence of hepatitis C virus (HCV) in normal cervical smears (CS) obtained from 22 HCV-seropositive and 50 HCV-seronegative patients was assessed by reverse-transcriptase-polymerase chain reaction (RT-PCR). The presence of HCV in serum was established by use of enzyme-linked immunosorbent assay, Western blot test, and RT-PCR. HCV was detected in 36.4% (n=8) of CS cells recovered from 22 HCV-seropositive patients, but not in CS samples obtained from 50 HCV-seronegative patients. Furthermore, cells from the CS of 2 seropositive/smear-positive patients and 1 seropositive/smear-negative patient were isolated; HCV RNA was detectable in the cervical lymphocytes of the 2 smear-positive patients, but not in epithelial cells or granulocytes. HCV RNA is detectable in the CS of some HCV-seropositive women. The clinical importance of these data requires further study.

Factors related to the chronicity and evolution of hepatitis C infection in patients co-infected by the human immunodeficiency virus

Objectives This work analyses the influence of immune status, serum human immunodeficiency virus (HIV) load and hepatitis C virus (HCV) genotypes on the probability of resolution of HCV infection in HIV-co-infected patients, as well as the evolution of HCV viremia after antiretroviral therapy.Patients and methods Forty-five patients with anti-HIV and anti-HCV antibodies were classified into two groups as a function of the positivity or persistent negativity of HCV RNA detection (active or recovered HCV infection, respectively). They were treated with highly active antiretroviral therapy (HAART). Serum HCV RNA was quantified by the reverse transcription-polymerase chain reaction. HCV genotypes were detected by line probe assay or by detection of type-specific antibodies.Results HCV RNA was detectable in 30 (66.6%) out of 45 HIV-infected patients. CD4+ T-cell counts, HIV viremia, or HCV genotypes were similar in patients with active or recovered HCV infection. Patients with active HCV infection had a non-significant decrease of HCV viremia during a follow-up of 12 months (from 6.15 ± 6.32 to 5.96 ± 6.05 log copies/mL). This was not influenced by baseline HCV or HIV viral load, HCV genotype, or CD4+ T-cell count. The non-significant decrease was present in patients with or without an immunological response to HAART.Conclusion HCV genotypes, immune status, or serum HIV load did not influence the resolution or chronicity of HCV infection in HIV-co-infected individuals. A non-significant decrease of HCV viremia in these patients treated with combinations including antiproteases could be expected.

Lack of Association Between Hepatitis C Viral RNA in Serum and Liver and Histologic Gradings: A Study on Irish Anti-D-Treated Patients

In this study the authors applied a reverse transcription-polymerase chain reaction (RT-PCR) assay to detect hepatitis C virus (HCV) RNA in 15 frozen liver biopsy samples from anti-D-treated patients. They also correlated the presence or absence of HCV RNA in the serum and liver of each patient with their histologic gradings. RNA was extracted from 36 frozen liver biopsy samples. These included 15 liver biopsy samples from patients infected with HCV through contamination of anti-D blood products. Three of these 15 anti-D-treated patients were receiving alpha-interferon treatment at the time of liver biopsy. Nine frozen liver biopsy samples from patients with a history of intravenous drug abuse were included as positive controls. HCV-negative frozen liver biopsy samples from 12 noninfected patients were used as negative controls. RNA was also extracted from six frozen skin biopsy specimens to check for cross-contamination of samples. Eleven of 15 anti-D-treated patients were HCV RNA positive by RT-PCR, with 100% correlation between HCV RNA in the serum and liver. The nine frozen liver biopsy samples from the intravenous drug abuse patients (positive controls) were also RT-PCR positive for HCV RNA. The 12 noninfected samples and the negative control biopsy samples were negative for HCV. Twenty-seven percent of the recombinant immunoblot assay-positive patients were serum and liver HCV RNA negative. HCV-positive patients receiving alpha-interferon therapy at the time of biopsy had cleared the virus from the serum and the liver. There was no correlation between the presence or absence of serum and liver HCV RNA with the histologic grading. This lack of correlation shows clearly the importance of histopathologic evaluation of liver biopsy samples in monitoring HCV-associated liver disease progression. In addition, this finding indicates that one cannot rely only on the presence or absence of HCV RNA in either serum or liver tissue as a parameter in monitoring HCV-associated liver disease progression in this unique cohort of anti-D-treated patients.

Factors predictive of response to interferon-alpha therapy in hepatitis C virus type 1b infection.

Interferon-alpha (IFN-alpha) has been used to treat hepatitis C Virus (HCV)-induced infection but has been effective in only about half of all patients. It is suggested that the different responses to IFN-alpha treatment in HCV infection may be influenced by HCV genotypes, HCV RNA titer at the beginning of IFN-alpha therapy, and the sequences of the interferon sensitivity determining region (ISDR). However, there have also been reports showing that these have no relation to an IFN-alpha effect. In a previous study, it was found that the nucleotide sequence variation in the hypervariable region (HVR) 1 of the HCV could predict the effect of IFN-alpha. In the present investigation, an attempt was made to determine the predictive factors of IFN-alpha therapy. Twenty-six patients with HCV infection were treated with IFN-alpha. Among these, 13 patients recovered after 3 to 6 months of IFN-alpha treatment, although the other 13 patients showed no response after 6 months of treatment with IFN-alpha. In order to determine the predictive factors of IFN-alpha therapy, the ALT levels, HCV genotypes, HCV serum titer, and the quasispecies of HVR 1 were compared between responders and non-responders. It is suggested that the variation in the HVR 1 and HCV serum titer can be used to predict the effect of IFN-alpha.

Identification of B cell epitopes of hepatitis C virus RNA dependent RNA polymerase

The aim of this study was to identify the B cell epitopes of hepatitis C virus (HCV) NS5B RNA dependent RNA polymerase (RdRp). The truncated HCV NS5B protein NS5B-dc21 was expressed in Escherichia coli and its antigenicity was confirmed by Enzyme-Linked Immunosorbent Assay (ELISA) using 130 HCV-positive human sera and 15 negative sera. Antibodies specific to NS5B-dc21 protein were purified by affinity chromatography using sepharose-4B coupled with the recombinant protein. A 12-mer phage displayed random peptide library was screened four rounds with the purified antibodies. Three epitopes were identified from the phage library, which correspond to amino acids 2444–2452, 2521–2528, and 2915–2925 of HCV RdRp. These epitopes were then expressed in E. coli as fusion proteins with phage M13 pIII protein. ELISA demonstrated that two of these epitopes (P4 and P34, corresponding to amino acids 2443–2452 and amino acids 2512–2528, respectively) have good reactivity and sensitivity. Mutagenesis study of P4 peptide showed that this epitope, which is derived from a phage displayed library, exhibited higher affinity with HCV serum than the corresponding original HCV sequences.

ADAM-HCV, a new-concept diagnostic assay for antibodies to hepatitis C virus in serum.

We screened phage libraries using sera from noninfected individuals and patients infected by hepatitis C virus (HCV). By applying different selection and maturation strategies, we identified a wide collection of efficient phage-borne ligands for HCV-specific antibodies. The selected ligands retained their antigenic properties when expressed as multimeric synthetic peptides. Peptides that mimic several immunodominant epitopes of the virus were used to develop a novel type of diagnostic assay which efficiently detects antibodies to HCV in serum. This type of analysis provides a conclusive diagnosis for many patients identified as indeterminate according to presently available serological assays.

Assessment of hepatitis C virus RNA and genotype from 6807 patients with chronic hepatitis C in the United States.

Hepatitis C virus (HCV) RNA status and HCV genotype have become important tools in the diagnosis and monitoring of therapy in chronic HCV infection. To establish a database with respect to HCV genotype and serum HCV RNA concentrations in chronic hepatitis C patients in the United States, we analysed 6807 chronic hepatitis C patients who had HCV RNA and HCV genotype tests conducted at a central laboratory. The HCV RNA concentration cut-off for the lower 25th percentile of this population (low titre) was 0.9 x 106 copies ml-1. The median HCV RNA concentration was 3.5 x 106 copies ml-1 and the cut-off for the upper 25th percentile (high titre) was 5 x 106 copies ml-1. Male patients had a median HCV RNA concentration of 3.9 x 106 copies ml-1, which was significantly higher than the median HCV RNA level for females (2.75 x 106 copies ml-1; P < 0.001). HCV genotype 1 was detected in 73% of patients; genotype 2 in 14%; genotype 3 in 8%; mixed genotype in 4%; and genotypes 4, 5 and 6 with a frequency of < 1%. Patients from the Northeast, Southeast and Midwest had significantly (P < 0.001) more infections with genotype 1 than patients from the Western and Southern regions. African-American patients were more likely to be infected with genotype 1 when compared with Caucasian, Hispanic or Asian Pacific Islanders (P < 0.001). Patients infected with HCV genotype 1 and mixed HCV genotypes had significantly higher serum HCV RNA concentrations when compared with HCV genotypes 2 and 3 (P < 0.001 for all comparisons).

TT virus infection in patients with chronic hepatitis B or C: influence on clinical, histological and virological features.

Concomitant infection with TT virus and hepatitis B virus (HBV) or hepatitis C virus (HCV) is common. However, the effect of TTV infection on chronic hepatitis B or C is unknown. The prevalence of TTV infection, the effect of TTV infection on the clinical, histological and virological features of patients with chronic hepatitis B or C, and the influence of TTV infection on the HCV response to interferon alfa therapy were studied. A total of 100 asymptomatic hepatitis B surface antigen carriers, 220 patients with HBV-related chronic liver diseases, and 110 patients with chronic hepatitis C treated with interferon alfa (3 million units subcutaneously three times a week for 24 weeks) were enrolled. Serum HCV RNA and serum TTV DNA were detected by the polymerase chain reaction (PCR). Serum HBV DNA and serum HCV RNA level were quantified by branched DNA assays. Infection with TTV was detected in 21.5% of HBV carriers and 37% of HCV carriers. TTV infection had little effect on the clinicopathological course of chronic HBV infection. In chronic hepatitis C, clinical features, histological severity, serum HCV RNA levels, and the response to interferon alfa therapy did not differ between those with and without TTV infection. The loss of serum TTV DNA did not correlate with the biochemical response as did in the loss of serum HCV RNA. In conclusion, TTV infection is found frequently in patients with chronic hepatitis B or C in Taiwan; however, coinfection with TTV does not affect the clinicopathological course of chronic hepatitis B or C and the response to interferon alfa therapy.

Detection of Epstein-Barr Virus DNA in Hepatocellular Carcinoma Tissues from Hepatitis C-positive Patients

Background: We have previously shown that hepatitis C virus (HCV) replication is promoted by the Epstein-Barr virus (EBV) in vitro. The aim of this study was to examine the EBV load in hepatocellular carcinoma (HCC) tissues from HCV antibody-positive patients. Methods: DNA was extracted from paraffin sections from 168 HCC patients. After amplification of a region in the EBV BamHI W sequence by means of the polymerase chain reaction (PCR), it was detected by Southern hybridization and semi-quantified. Ten hyperplastic lesions from HCV-positive patients and 35 non-tumorous samples from hepatitis-negative patients served as controls. The PCR results were analyzed on the basis of the patient's hepatitis status. Univariate and multivariate analyses were performed to identify clinicopathologic factors for predicting EBV infection in HCC tissues. Results: More than one copy of EBV DNA per 100 cells was detected in 56 (33%) of the HCC sections. The detection ratio in HCC tissues from HCV antibody-positive patients was 40% (45 of 113), which was significantly higher than that in tissues from HBV surface antigen-positive patients (14%, 5 of 37; P = 0.0018). The patient's serum HBV surface antigen and HCV antibody independently predicted the EBV positivity of HCC tissues. Conclusions: These results support our hypothesis that EBV could play an important role in the development of HCV-related HCC.

Increased frequency of interferon-gamma-producing peripheral blood CD4+ T cells in chronic hepatitis C virus infection.

To determine the profile of cytokine secretion by CD4+ T helper (Th) cells in chronic hepatitis C virus (HCV) infection, we used flow cytometry to determine the percentage of interferon (IFN)-gamma and interleukin (IL)-4 producing cells from CD4+ T lymphocytes in peripheral blood obtained from patients chronically infected with HCV. Peripheral blood mononuclear cells isolated from 89 HCV infected subjects (22 asymptomatic carriers, 56 patients with chronic hepatitis, and 11 patients with liver cirrhosis) and 24 healthy controls were stained with surface CD4 and intracellular IFN-gamma and IL-4. Serum soluble IL-2 receptor (sIL-2R) levels were analyzed by ELISA. The frequency of IFN-gamma producing CD4+ cells in asymptomatic HCV carriers, patients with chronic hepatitis, and patients with liver cirrhosis were significantly higher than those of healthy controls (p<0.01, respectively). In contrast, the percentages of IL-4-producing CD4+ cells were very low, and there were no significant correlations with disease progression. A significant elevation in serum sIL-2R levels was found in chronic HCV infection compared to healthy controls, and serum sIL-2R levels significantly correlated with the frequency of IFN-gamma-producing cells. In HCV infected subjects, both serum sIL-2R and IFN-gamma are increased in chronic HCV infection no matter the stage of disease, meaning they are no different in asymptomatic carriers, patients with chronic hepatitis, and patients with liver cirrhosis, and that Th1 cytokine or Th1 cells may participate in the pathogenesis of liver damage in chronic HCV infection.

Increased frequency of interferon-γ-producing peripheral blood CD4 + T cells in chronic hepatitis C virus infection

OBJECTIVES: To determine the profile of cytokine secretion by CD4 + T helper (Th) cells in chronic hepatitis C virus (HCV) infection, we used flow cytometry to determine the percentage of interferon (IFN)-γ and interleukin (IL)-4 producing cells from CD4 + T lymphocytes in peripheral blood obtained from patients chronically infected with HCV. METHODS: Peripheral blood mononuclear cells isolated from 89 HCV infected subjects (22 asymptomatic carriers, 56 patients with chronic hepatitis, and 11 patients with liver cirrhosis) and 24 healthy controls were stained with surface CD4 and intracellular IFN-γ and IL-4. Serum soluble IL-2 receptor (sIL-2R) levels were analyzed by ELISA. RESULTS: The frequency of IFN-γ producing CD4 + cells in asymptomatic HCV carriers, patients with chronic hepatitis, and patients with liver cirrhosis were significantly higher than those of healthy controls ( p < 0.01, respectively). In contrast, the percentages of IL-4-producing CD4 + cells were very low, and there were no significant correlations with disease progression. A significant elevation in serum sIL-2R levels was found in chronic HCV infection compared to healthy controls, and serum sIL-2R levels significantly correlated with the frequency of IFN-γ-producing cells. CONCLUSIONS: In HCV infected subjects, both serum sIL-2R and IFN-γ are increased in chronic HCV infection no matter the stage of disease, meaning they are no different in asymptomatic carriers, patients with chronic hepatitis, and patients with liver cirrhosis, and that Th1 cytokine or Th1 cells may participate in the pathogenesis of liver damage in chronic HCV infection.

Detection of hepatitis C virus RNA in the hearts of patients with hepatogenic cardiomyopathy.

We examined the Hepatitis C virus (HCV) genome in the myocardium and liver obtained at autopsy from seven patients with HCV-positive liver cirrhosis and hepatocellular carcinoma (HCC) by in situ hybridization and histopathological studies. The HCV virus genome was detected in the myocardium of one patient as well as in the liver in three out of seven patients. However, Epstein-Barr (EB) virus genome could not be detected in liver or myocardium. In the patient who showed positive reaction to HCV in myocardium, both serum HCV and Hepatitis B virus (HBV) antibodies were positive. It is unknown whether this was related to an immunological abnormality of the host or to an interaction between RNA and DNA viruses. In conclusion, we could identify the HCV genome in the myocardium of a patient with hepatogenic myocardosis.

Quantitative Assessment of HCV Load in Chronic Hemodialysis Patients: A Cross-Sectional Survey

Recent evidence has been accumulated showing that chronic hemodialysis (HD) patients have a very high prevalence of antibodies to hepatitis C virus (HCV). In contrast, there is little information addressing the virological characteristics of HCV infection in this population. Aim: To measure HCV viral load and to correlate this with demographic, biochemical, and clinical features of a large cohort of HCV-infected patients on chronic HD. Methods: 394 chronic HD patients were tested by branched-DNA signal amplification assay, anti-HCV enzyme-linked immunosorbent assay 2.0, and on the basis of the aspartate aminotransferase/alanine aminotransferase (AST/ALT) activity. Multivariate analysis by ordinal logistic regression model was performed: age, gender, race, time on HD, allocation of the patients among the HD units, etiology of end-stage renal disease, HBsAg status, anti-HCV positivity, HCV genotype, and AST/ALT levels were independent factors, and viremic levels of HCV in serum were assumed as dependent variables. Results: 88 (22.3%) patients showed serological and/or virological signs of HCV infection. 59 (15%) out of 394 had detectable HCV RNA in serum, the mean HCV load was 19.4 × 10⁵ (95% CI, 6.06 × 10⁷ to 6.2 × 10⁴) Eq/ml. According to the criteria suggested by others [J Infect Dis 1994;169:1219–1225], there were 8 (13.5%) individuals with high-titer viremia (>1 × 10⁷ Eq/ml) in the subset of viremic patients. A small subset (8/394 or 2%) of individuals was seronegative, but viremic; 29 (7%) out of 394 were seropositive without detectable HCV RNA in serum. Univariate analysis showed that the frequency of anti-HCV positivity was significantly higher in viremic patients as compared with individuals with no detectable HCV viremia: 51/59 (86%) vs. 29/335 (8.6%), p = 0.0001. Serum AST and ALT levels were significantly higher in viremic patients than in individuals with no detectable HCV RNA in serum: 23.8 (95% CI 60.8–9.3) vs. 17.1 (95% CI 50.4–5.8) U/l (p = 0.009) and 14.4 (95% CI 48.9–4.3) vs. 9.8 (95% CI, 37.3– 2.5) U/l (p = 0.008). Logistic regression analysis showed an association between HCV viremia and anti-HCV positivity (p = 0.00001) and ALT activity (p = 0.01). Conclusions: Hepatitis C virus infection is highly prevalent in the HD population; the viral load is relatively low, and it was associated with elevated hepatic enzyme levels and anti-HCV positivity. No other clinical characteristics were associated with HCV RNA levels. Seronegative but viremic patients were also found. Longitudinal studies with long follow-up periods are necessary to evaluate the course of HCV load over time in this population.

BRIEF COMMUNICATION: Efficacy of ribavirin plus interferon α on viraemia of GB virus‐C/hepatitis G virus: Comparison with interferon α 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.

Randomised trial of interferon α2b plus ribavirin for 48 weeks or for 24 weeks versus interferon α2b plus placebo for 48 weeks for treatment of chronic infection with hepatitis C virus

Background: Only 15–20% of patients with chronic hepatitis C achieve a sustained virological response with interferon therapy. The aim of this study was to compare the efficacy and safety of interferon α2b in combination with oral ribavirin with interferon alone, for treatment of chronic infection with hepatitis C virus (HCV). Methods: 832 patients aged 18 years or more with chronic HCV who had not been treated with interferon or ribavirin, were enrolled and randomly allocated one of three regimens: 3 mega units (MU) interferon α2b three times a week plus 1000–1200 mg ribavirin per day for 48 weeks; 3 MU interferon α2b three times a week plus 1000–1200 mg ribavirin per day for 24 weeks; or 3 MU interferon α2b three times a week and placebo for 48 weeks. All patients were assessed for safety, tolerance, and efficacy at the end of weeks 1, 2, 4, 6, and 8, and every 4 weeks during treatment. After treatment was completed patients were followed up on weeks 4, 8, 12, and 24. The primary endpoint was loss of detectable HCV*RNA (serum HCV*RNA < 100 copies/mL) at week 24 after treatment. Findings: Sustained virological response at 24 weeks after treatment, was found in 119 (43%) of the 277 patients treated for 48 weeks with the combination regimen, 97 (35%) of the 277 patients treated for 24 weeks with the combination regimen (p < 0.055), and 53 (19%) of the 278 patients treated for 48 weeks with interferon alone (p < 0.001 vs both combination regimens, intention to treat analysis). Logistic regression identified five independent factors significantly associated with response: genotype 2 or 3, viral load less than 2 million copies/mL, age 40 years of less, minimal fibrosis stage, and female sex. Among patients with fewer than three of these factors the odds ratio of sustained response was 2.6 (95% CI; 1.4–4.8; p = 0.002) for the 48 week combination regimen compared with 24 weeks of the combination regimen. Disoon-tinuation of therapy for adverse events was more frequent with combination (19%) and monotherapy (13%) given for 48 weeks than combination therapy given for 24 weeks (8%). Interpretation: An interferon α2b plus ribavirin combination is more effective than 48 weeks of interferon α2b monotherapy and has an acceptable safety profile. Patients with few favourable factors benefit more from extending the duration of combination therapy to 48 weeks.