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HCV Subtype (hcv + subtype)
Selected AbstractsPredictors of the efficacy of interferon therapy for patients with chronic hepatitis C before and during therapy: how does this modify the treatment course?JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2000Yasushi Shiratori Antiviral therapy for hepatitis C virus (HCV) infection should be based on the natural history of HCV infection; there is a sequential, but slow, progression from chronic hepatitis to cirrhosis, leading to death from either liver failure or hepatocellular carcinoma (HCC). The risk of HCC development increases in association with the advance of fibrosis, and antiviral therapy can reduce this risk. More than 30 indices have been proposed as ,predictors' of favourable response to IFN therapy: host factors (age, gender, duration of HCV-infection, alcohol intake, hepatic iron stores, platelet count, histological staging of the liver disease), viral factors (HCV RNA levels in serum, HCV subtype, diversity of the hypervariable region, mutation of non-structure 5A gene), and IFN factors (dose, duration of treatment, type, treatment regimens i.e. every day vs three times a week, escalating dose regimen). Before starting IFN therapy, HCV subtype and pretreatment HCV RNA load, as well as the fibrotic stage of the liver, should be determined. The response to IFN therapy should be monitored by the HCV RNA status in serum during therapy, and the treatment regimen modified, or discontinued as required. A sustained virological response should be checked at more than 3 months after the completion of therapy. Even though the risk of HCC is markedly reduced in sustained responders, it is possible to develop HCC several years after completion of IFN therapy. [source] Genetic characterization of hepatitis C virus strains in Estonia: Fluctuations in the predominating subtype with timeJOURNAL OF MEDICAL VIROLOGY, Issue 4 2007Tatjana Tallo Abstract During the last decade, there has been a dramatic increase in intravenous drug use in young adults in Estonia with an increased incidence of both hepatitis B and C as a consequence. Since genetic data are limited regarding hepatitis C virus (HCV) strains in Estonia, the aim of the study was to characterize HCV strains in different risk groups to determine their relatedness to strains from other geographical regions. Three hundred fifty-three anti-HCV positive sera collected during 1994,2004 from hospitalized patients, blood donors and health care workers were used as source of HCV RNA. Two hundred nine (59%) of the sera were positive for HCV RNA by PCR directed to the 5,-UTR region. For 174 strains the HCV subtype was determined by analyses of the NS5B and/or the 5,UTR-core regions. 1b (71%) was the most common subtype followed by 3a (24%), 2c (2%), 1a (1%), and 2a (1%). The 1b and 3a strains were similar to strains from other regions of the former USSR. Within genotype 1b there were several HCV lineages. However, for 3a there seemed to be two separate introductions into Estonia. There was a relative shift from subtype 1b to 3a in 1999,2000 with a further replacement of 3a with 1b in intravenous drug users in 2001 and onwards (P,<,0.05). However, both subtypes were found to co-circulate in the community independent of risk factors. One patient was infected with the 2k/1b recombinant presumed to originate from St. Petersburg being the first isolate of this recombinant recovered outside Russia. J. Med. Virol. 79:374,382, 2007. © 2007 Wiley-Liss, Inc. [source] Human immunodeficiency virus type 1 and hepatitis C virus Co-infection and viral subtypes at an HIV testing center in BrazilJOURNAL OF MEDICAL VIROLOGY, Issue 6 2006G.A.S. Pereira Abstract Human immunodeficiency virus (HIV) testing sites have been recognized recently as potential settings for hepatitis C virus (HCV) screening since both viruses share common routes of transmission. HIV and HCV prevalence, predictors, co-infection rates, and viral subtypes were studied in 592 attendants at an anonymous HIV Counseling and Testing Center in central Brazil. Anti-HIV-1 and -HCV antibodies were screened by ELISA, and Western blots were used to confirm HIV infection. Among HIV-seropositive samples, reverse transcriptase-polymerase chain reaction (RT-PCR) and nested-PCR were used to subtype HIV-1 by the Heteroduplex Mobility Analysis (HMA) and HCV by the line probe assay (INNO-LiPA). HIV and HCV seroprevalence was 3.2% (95% CI 2.0,4.9) and 2.5% (95% CI 1.5,4.0), respectively. Intravenous drug use was the risk factor most strongly associated with both HIV and HCV infections, even in a population with few intravenous drug users (n,=,6); incarceration was also associated with HCV. HIV/AIDS-positive sexual partner and homosexual/bisexual behaviors were associated independently with HIV-1. The prevalence of HCV infection among HIV-positive persons was 42% (95% CI 20,66), higher than in HIV-negative persons (1.2%; 95% CI 0.5,2.5). HIV-1 subtype B was identified in the env and gag regions of the genome. HCV subtype 3a predominated among co-infected persons and one HCV subtype 1a was detected. Overall, a similar prevalence of HIV and HCV infections and a higher prevalence of HCV among HIV-positive persons were observed. Integrated HIV and HCV screening at HIV testing sites may represent a unique opportunity to provide diagnosis and prevention strategies at a single visit. J. Med. Virol. 78:719,723, 2006. © 2006 Wiley-Liss, Inc. [source] Epidemiological characteristics and response to peginterferon plus ribavirin treatment of hepatitis C virus genotype 4 infectionJOURNAL OF VIRAL HEPATITIS, Issue 7 2007D. Roulot Summary., Hepatitis C virus genotype 4 (HCV-4) infection is progressing in Europe, where epidemiology and sustained virological response (SVR) seem to be different than in the Middle East. We analysed epidemiological features and SVR rates in a retrospective study of 1532 HCV-4-infected patients, including 1056 patients infected in France, 227 immigrants infected in Egypt and 249 in sub-Saharan Africa. SVR rates were assessed in 242 naive patients of the 1532, who received peginterferon plus ribavirin for 48 weeks. HCV subtype 4a or 4d was the most common among patients infected in France, where the predominant route of transmission was intravenous drug abuse. The 4a subtype was largely predominant (93%) among patients infected in Egypt, where transmission was mostly because of parenteral treatment for schistosomiasis. More than seven different subtypes and no predominant route of infection were found in patients infected in sub-Saharan Africa. Liver fibrosis was significantly less severe in patients infected in France and Africa than in patients infected in Egypt. SVR rates were higher in patients infected in Egypt, compared with those infected in France or Africa (54.9%, 40.3% and 32.4%, respectively, P < 0.05). An overall better response was observed in patients infected with the 4a subtype. In multivariate analysis, two factors were associated independently with SVR: the Egyptian origin of transmission and the absence of severe fibrosis. In conclusion, the distribution of HCV-4 subtypes varies with the geographical origin of transmission and affects the SVR following antiviral treatment. [source] Genotype diversity of hepatitis C virus (HCV) in HCV-associated liver disease patients in IndonesiaLIVER INTERNATIONAL, Issue 8 2010Andi Utama Abstract Background: Hepatitis C virus (HCV) genotype distribution in Indonesia has been reported. However, the identification of HCV genotype was based on 5,-UTR or NS5B sequence. Aims: This study was aimed to observe HCV core sequence variation among HCV-associated liver disease patients in Jakarta, and to analyse the HCV genotype diversity based on the core sequence. Methods: Sixty-eight chronic hepatitis (CH), 48 liver cirrhosis (LC) and 34 hepatocellular carcinoma (HCC) were included in this study. HCV core variation was analysed by direct sequencing. Results: Alignment of HCV core sequences demonstrated that the core sequence was relatively varied among the genotype. Indeed, 237 bases of the core sequence could classify the HCV subtype; however, 236 bases failed to differentiate several subtypes. Based on 237 bases of the core sequences, the HCV strains were classified into genotypes 1 (subtypes 1a, 1b and 1c), 2 (subtypes 2a, 2e and 2f) and 3 (subtypes 3a and 3k). The HCV 1b (47.3%) was the most prevalent, followed by subtypes 1c (18.7%), 3k (10.7%), 2a (10.0%), 1a (6.7%), 2e (5.3%), 2f (0.7%) and 3a (0.7%). HCV 1b was the most common in all patients, and the prevalence increased with the severity of liver disease (36.8% in CH, 54.2% in LC and 58.8% in HCC). These results were similar to a previous report based on NS5B sequence analysis. Conclusion: Hepatitis C virus core sequence (237 bases) could identify the HCV subtype and the prevalence of HCV subtype based on core sequence was similar to those based on the NS5B region. [source] A prospective study of interferon therapy modified by pre-treatment viral load in cirrhotic patientsLIVER INTERNATIONAL, Issue 4 2000Yasushi Shiratori Abstract:Background/Aims: The relative role of hepatitis C virus (HCV) load and subtype as predictors of the efficacy of interferon therapy has been clarified in patients with chronic hepatitis C, but the effectiveness of interferon therapy in cirrhotic patients is still unclear. Methods: To resolve this issue, we undertook a multicenter, randomized, and prospective study of 114 cirrhotic patients with hepatitis C virus infection. The patients were selected to undergo two different periods (6 or 12 months) of IFN therapy according to viral load. Patients with "low" viral load (,105.8 copies/ml serum) were randomly divided into three groups, receiving 6 or 9 million units (MU) interferon three times a week for 6 months (total dose: 468 or 702 MU), or of a modified regimen using 6MU of IFN over 6 months (total dose 564 MU), while patients with "high" viral load (,106.3 copies/ml serum) were also randomly divided into two groups of 6 or 9 MU of IFN three times a week for 12 months (total dose: 936 or 1404 MU). Results: HCV-RNA negativity rate at the completion of treatment with 6 or 9 MU IFN was 65% in patients with "low" viral load, in contrast to 14% in patients with "high" viral load. Sustained virological response was found in 40% of patients with "low" viral load irrespective of the three different regimens, in contrast to only 1 out of 35 patients (3%) with "high" viral load. Viral eradication was found in approximately 50% of patients having a low virus load (,104.3 copies/ml) and with HCV subtype 2a. Univariate and multivariate analysis revealed that pretreatment viral load was a significant factor contributing to efficacy of IFN therapy. Conclusions: Sustained response was scarcely achieved in cirrhotic patients with high viral loads even after a 12-month course of intensive IFN therapy. This result indicates that there is a certain cut-off level of HCV RNA load which can not be eradicated. [source] Transcription-mediated amplification linked to line probe assay as a routine tool for HCV typing in clinical laboratories,JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 5 2007R.S. Ross Abstract Typing of hepatitis C virus (HCV) isolates is currently a prerequisite for adequate tailoring of antiviral combination therapy. In many diagnostic laboratories, there seems to be a tendency toward convenient and time-saving procedures utilizing amplification products, which are already available from preceding qualitative or quantitative HCV ribonucleic acid (RNA) assays. In this context, we evaluated the performance characteristics of a combination of techniques, i.e., transcription-mediated amplification-line probe assay (TMA-LiPA), which links highly sensitive TMA of HCV RNA to the VERSANT HCV Genotype Assay (version 1). A total of 100 clinical samples were genotyped by TMA-LiPA. The obtained results were compared to those recorded by the original, nested reverse transcription (RT)-polymerase chain reaction (PCR)-based VERSANT assay, the core-related GEN-ETI-K DEIA, and phylogenetic analyses of partial sequences from the HCV core and NS5B regions. TMA-LiPA assigned the correct genotype to all 100 HCV isolates. For subtyping of genotype 1 and 2 isolates, TMA-LiPA only showed discriminatory powers of 82% and 53%, respectively. Thus, TMA-LiPA in our hands turned out as a convenient and time-saving routine procedure for HCV typing which currently provides sufficient information for clinical purposes. Like all 5,untranslated region (UTR)-based assays, the technique is limited, however, in its potentials to resolve the complexity of existing HCV subtypes. J. Clin. Lab. Anal. 21:340,347, 2007. © 2007 Wiley-Liss, Inc. [source] Refined analysis of genetic variability parameters in hepatitis C virus and the ability to predict antiviral treatment responseJOURNAL OF VIRAL HEPATITIS, Issue 8 2008J. M. Cuevas Summary., Hepatitis C virus (HCV) infects approximately 3% of the world population. The chronicity of hepatitis C seems to depend on the level of genetic variability. We have recently (Torres-Puente et al., J Viral Hepat, 2008; 15: 188) reported genetic variability estimates from a large-scale sequence analysis of 67 patients infected with HCV subtypes 1a (23 patients) and 1b (44 patients) and related them to response, or lack of, to alpha-interferon plus ribavirin treatment.. Two HCV genome regions were analysed in samples prior to antiviral therapy, one compressing the three hypervariable regions of the E2 glycoprotein and another one including the interferon sensitive determining region and the V3 domain of the NS5A protein. Haplotype and nucleotide diversity measures showed a clear tendency to higher genetic variability levels in nonresponder than in responder patients. Here, we have refined the analysis of genetic variability (haplotype and nucleotide diversity, number of haplotypes and mutations) by considering their distribution in each of the biologically meaningful subregions mentioned above, as well as in their surrounding and intervening regions. Variability levels are very heterogeneous among the different subregions, being higher for nonresponder patients. Interestingly, significant differences were detected in the biologically relevant regions, but also in the surrounding regions, suggesting that the level of variability of the whole HCV genome, rather than exclusively that from the hypervariable regions, is the main indicator of the treatment response. Finally, the number of haplotypes and mutations seem to be better discriminators than haplotype and nucleotide diversity, especially in the NS5A region. [source] | ||||||||||