Hepatitis C Virus Serotype Research Articles

CCR5 Promoter Polymorphism Influences the Interferon Response of Patients with Chronic Hepatitis C in Japan

Objective: Chemokines and chemokine receptors play important roles in the pathogenesis of chronic hepatitis C. Here, we explore the influence of genetic polymorphisms of chemokine and chemokine receptors such as regulated upon activation and T cell secreted (RANTES), CC chemokine receptor 5 (CCR5) and CCR2 on the outcome of interferon (IFN) monotherapy. Methods: In a cohort of 105 patients with chronic hepatitis C as well as in 50 sustained responders and 55 nonresponders the presence of polymorphisms such as CCR5-Δ32, CCR5 59029G/A, CCR2 V64I and RANTES –403G/C was determined. Results: Gender, age, liver histological staging, pretreatment ALT levels, total dose of IFN and frequencies of polymorphisms (CCR2 V64I and RANTES –403G/C) did not significantly differ between the two groups. A low viral load, hepatitis C virus (HCV) serotype 2 and CCR5 59029G/G were significantly associated with a higher probability of a sustained response (p < 0.01, p < 0.05, p < 0.05, respectively). Multiple logistic regression analysis showed that a low viral load, HCV serotype 2 and CCR5 59029G/G were independently associated with a sustained response [odds ratio 3.980 (1.647–9.621), p = 0.002; 3.584 (1.439–8.924), p = 0.006; 3.638 (1.163–11.379), p = 0.026, respectively]. Conclusion: These findings indicate that CCR5 59029 is a host genetic factor that is associated with responses to IFN therapy among Japanese patients with chronic hepatitis C.

Hepatic steatosis is a risk factor for hepatocellular carcinoma in patients with chronic hepatitis C virus infection.

Hepatic steatosis is one of the histopathologic features of chronic hepatitis C. It was reported recently that the expression of hepatitis C virus (HCV) core protein in transgenic mice induced hepatocellular carcinoma (HCC) in association with steatosis. The objective of this study was to determine the relation between hepatic steatosis and hepatocarcinogenesis in patients with chronic HCV infection. The authors studied 161 patients with chronic HCV infection who were diagnosed at Nagasaki University Hospital, Nagasaki, Japan, between January 1980 and December 1999. Age, gender, body mass index (BMI), habitual drinking, diabetes mellitus, serum alanine aminotransferase (ALT) level, HCV serotype, serum level of HCV core protein, interferon (IFN) treatment, hepatic fibrosis inflammation, and hepatic steatosis were studied with regard to their significance in the development of HCC using univariate and multivariate analyses. The cumulative incidence rates of HCC were 24%, 51%, and 63% at 5 years, 10 years, and 15 years, respectively. Multivariate analysis identified hepatic steatosis, together with aging, cirrhosis, and no IFN treatment, as independent and significant risk factors for HCC (P = 0.0135, P = 0.0390, P = 0.0068, and P = 0.0142, respectively). In addition, hepatic steatosis was correlated with BMI, serum ALT levels, and triglyceride levels. The findings of the current study indicate that hepatic steatosis is a risk factor for HCC in patients with chronic HCV infection. Patients with chronic HCV and hepatic steatosis should be monitored carefully for HCC.

Serotyping and genotyping of hepatitis C virus in Belgium.

Given that both pathogenicity and the response to treatment are possibly associated with hepatitis C virus (HCV) serotype, it appeared sensible to establish the prevalence of the different HCV types in Belgium. The HCV serotypes were determined in 68 HCV-RNA and anti-HCV-positive samples taken from Belgian patients and compared with the results of the genotyping assay. Possible associations with age and sex were investigated. Antibodies were identified in 55 (80.9%) of the 68 samples, with serotype 1 (58.8%) and serotype 3 (19.1%) showing the highest prevalence. 17 samples contained several serotypes with serotype 1 being detected in 82.4% of cases. Nine of the 11 samples undetermined by serotyping could be determined by genotyping. There was no significant difference in the distribution of HCV types with respect to gender. Compared with genotype 3 (p < 0.01) and genotypes 2 and 4 (p = 0.05), genotype 1 was detected among older patients. Our data showed a 96.0% correlation between the serotyping and genotyping assays. Genotypes 1 and 3 are the most prevalent types among Belgian patients. The data suggest that genotype 1 spread earlier than genotypes 2, 3 and 4. This corroborates previous European studies.

Comparative analysis of viral titers and histologic features of Pakistani patients infected with hepatitis C virus type 3

Background: Serum hepatitis C virus (HCV) RNA levels and genotypes are considered to be important determinants of the response to interferon treatment. Generally, patterns of viral loads have been reported for HCV type 1 infections and categorized as low- or high-level viremia. We studied the distribution of HCV RNA levels in patients predominantly infected with HCV type 3 and correlated it with hepatic damage. Methods: Serum HCV RNA levels and HCV serotypes were determined in 245 anti-HCV-positive patients representing all the major ethnic groups of Pakistan. Patients were grouped according to their HCV RNA levels as: level I (up to 50th percentile); level 11 (50th to 75th percentile); and level III (>75th percentile). Results: Sixty-one patients (25%) had high-level viremia (level 111) of 13.9 mega equivalent per milliliter (MEq/mL) or greater. These were more likely to be males (48 versus 13, P<0.05). A higher viral load correlated with advanced levels of fatty changes in liver. HCV type 3 was found in 68% of the samples, and type 1 in 14%; the rest were undefined. Mean HCV RNA levels were lower in patients infected with HCV type 3 than in patients infected with HCV type 1 (8.63 MEq/mL versus 37 MEq/mL; P < 0.001). Conclusions: Most patients with HCV type 3 infection had viremia that was significantly lower than that in HCV type 1-infected patients. This may be the reason for the better response to treatment usually seen in such cases. The severity of histologic changes was not associated with HCV type 3 viremia levels.

HCV serotypes in Brazilian patients

Objective: To investigate the prevalence of the different types of hepatitis C virus (HCV) in a population of chronic HCV carriers using the Murex HCV serotyping 1–6 assay. Methods: All serum samples from these patients had a positive nested PCR HCV reaction. The sera were submitted to ELISA, modified, for the identification of antibodies against HCV serotypes 1, 2, 3, 4, 5 and 6 (Murex HCV serotyping 1–6 assay). Results: The viral serotype was identified in 166 (75.8%) of the 219 patients, 108 (65.11%) males and 58 (34.9%) females. Patient age ranged from 12 to 73 years, with a mean of 41.1 years. The form of acquisition of the disease most frequently reported was blood transfusion. The results showed a predominance of type 1 (70.0%), followed by type 3 (22.3%) and type 2 (4.2%). Conclusion: Samples presenting low and very close optical density readings may lead to discrepant diagnoses concerning HCV serotypes and should be confirmed by genotyping. The serotyping can be useful in clinical practice and can be of help in establishing the prognosis of the disease, also favoring epidemiologic studies independently of the technology required for genotyping tests.

Kinetics of the hepatitis C virus during interferon therapy as a marker of therapeutic response.

The viral load and subtype of hepatitis C virus (HCV) are predictors of the efficacy of interferon (IFN) therapy. The kinetics of HCV during IFN therapy have been described recently, suggesting that HCV infection is highly dynamic. These observations have raised the issue as to whether early monitoring of the viral load can help guide IFN therapy. We measured HCV-RNA levels at 0, 24 and 48 h after the start of IFN-alpha treatment (10 MU daily for 2 weeks and then three times weekly for 22 weeks) or IFN-beta treatment (6 MU daily for 6 weeks). Then we analyzed the relationship between HCV kinetics and therapeutic response using stepwise multivariate logistic regression analysis. The exponential decay slope of the viral load during the first 24 h, not the first 48 h or the next 24 h, was a predictor of viral eradication at 6 months after completion of the treatment (sustained response; P = 0.0023). This decay slope was not affected by the HCV serotype or the type of IFN used. Initial viral load and HCV serotype were also predictors, as reported previously (P < 0.0001 and P = 0.0347, respectively). We also proposed a model using a prognostic index that predicted a sustained response with more than 80% sensitivity, specificity and efficacy in an independent and external group of patients. This study demonstrated that the exponential decay slope of the viral load during the first 24 h was an important predictor of the response to IFN therapy as well as the initial viral load and HCV serotype. The model may also be useful for the clinical management of IFN therapy.

Hepatitis C virus clearance is prominent in women in an endemic area.

The clinical and virological backgrounds of cases with previous hepatitis C virus (HCV) infection (positive for HCV antibody (anti-HCV) and HCV-RNA negative) in an HCV endemic area were examined to identify factors related to the clearance of HCV. The study population comprised 3117 inhabitants, 1037 male and 2080 female, from an HCV endemic area. Hepatitis C virus antibody was detected by a passive haemagglutination test. The HCV-RNA and the HCV genotype were detected by using the polymerase chain reaction method. The HCV serotype was determined by enzyme immunoassay by using the peptides of the core region. Twenty-two per cent of the inhabitants were positive for anti-HCV, with males and the elderly having a significantly higher antibody titre (P < 0.01) than youths and females. Hepatitis C virus-RNA was detected in 78% of the HCV antibody-positive cases. The rate of HCV-RNA positivity was significantly higher in males than in females (P < 0.01). No relationship was found between HCV-RNA positivity and age. The HCV genotype 1b was the predominant genotype among the HCV-RNA-positive cases. Mixed genotypes (1b + 2a) were observed in 12% of cases, primarily in elderly males and females. In cases with previous HCV infection, serotype 1 was the most common serotype, and there appeared to be no relationship between the distribution of HCV serotypes and age and gender. There was a female predominance with regard to previous HCV infection, but not to being HCV carriers (P < 0.01). Gender, not HCV genotype, is the primary factor influencing HCV clearance.

Hepatitis C prevalence among Australian injecting drug users in the 1970s and profiles of virus genotypes in the 1970s and 1990s.

To examine the seroprevalence of hepatitis C virus (HCV) in the Australian injecting drug-using community in the 1970s, and to compare the profile of HCV genotypes with that seen in the 1990s. Investigation of stored sera that were collected from injecting drug users in the 1970s and comparison with sera collected in the 1990s. Inner Sydney, 1974-1975 and 1994-1996. The 1970s group comprised 141 consecutive injecting drug users who attended the Brisbane Street Methadone Clinic. The 1990s group comprised 88 consecutive, injecting drug users of European origin who were HCV antibody-positive and attended a primary healthcare facility (the Kirketon Road Centre). HCV antibody prevalence (1970s); profile of HCV serotypes (1970s and 1990s); and serological evidence of hepatitis A and B. 84% of the 1970s group were HCV antibody-positive, of whom 92% were infected with HCV serotype 1 and 1% with serotype 3. In contrast, in the 1990s group, 69% were infected with HCV serotype 1 and 25% with serotype 3. The HCV-positive subjects from the early group were more likely than those from the recent group to have serological evidence of previous HBV infection. The high prevalence of HCV among injecting drug users in the 1970s in Australia confirms an epidemic that has been present for at least 25 years. Over this period, the proportion of HCV genotype 1 infections has decreased and genotype 3 infections have emerged.

Serotyping strip immunoblot assay for assessing hepatitis C virus strains in dialysis patients

Recent accumulated evidence shows that dialysis patients are a high-risk group for hepatitis C virus (HCV) infection. Assessment of HCV genotype distribution among dialysis patients may be important because specific viral genotypes are associated with different clinical manifestations, disease progression, and response to antiviral therapy. However, polymerase chain reaction–based methods are cumbersome and unsuitable for analyzing large cohorts of dialysis patients with HCV. Instead, this information can be obtained by using a novel recombinant immunoblot assay (RIBA) recently developed for determining HCV serotype. The RIBA HCV serotyping strip immunoblot assay (SIA; Chiron Corporation, Emeryville, CA), is based on an immunoblot strip with five lanes of immobilized serotype-specific HCV peptides from the nonstructural (NS4) and core regions of the genomes of HCV types 1, 2, and 3. HCV serotype is deduced by determining the greatest intensity of reactivity to the NS4 serotype-specific HCV peptide band in relation to the internal control band (human immunoglobulin G) intensity on each strip. HCV core peptide reactivity is used only in the absence of NS4 reactivity. We compared RIBA HCV serotyping SIA with genotyping using sera from a large (n = 107) cohort of HCV-infected patients undergoing chronic hemodialysis (HD). We successfully serotyped 79 of 107 patients (74%) undergoing HD. We found a remarkable concordance (65 of 70 results; 93%) between RIBA HCV serotyping SIA and genotyping (line probe assay [LiPA]) techniques (Κ = 0.786) with sera from viremic patients infected with a known genotype. Only 5 of 70 patients (7%) had apparently discordant results. In a subset of patients (28 of 107 patients; 26%) not typed by RIBA HCV serotyping SIA, most (24 of 28 patients; 86%) were successfully genotyped by LiPA technology. It was possible to assess serotype reactivity in some patients (9 of 107 patients; 7%) who could not be genotyped. The distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. In conclusion, (1) we found good agreement between serotyping and genotyping methods in our large cohort of dialysis patients infected with HCV; (2) the impaired immunocompetence conferred by uremia may limit serotyping analysis in some HCV-infected patients undergoing HD; (3) RIBA HCV serotyping SIA may be useful in tracking transmission routes for HD patients who cleared the virus and have only anti-HCV antibody; and (4) the distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. Assessment of HCV strains appears to be very useful in the routine clinical activity of nephrologists within HD units because consistent biological differences among HCV strains exist. RIBA serotyping SIA is a simple, inexpensive, and highly reproducible assay to obtain information about HCV types in the HD setting.

Hepatitis C virus serotypes in haemodialysis patients in South-East Italy.

Hepatitis C virus (HCV) infection is highly prevalent in haemodialysis patients. To date, only a few studies involving a small number of subjects have characterized HCV-infected dialysis patients by serotyping. The spread of HCV serotypes in 114 HCV-positive dialysis patients from the same geographical area was evaluated by Murex HCV serotyping assay. Serotypes were detected in 102 subjects (89.5%), with type 1 being the most frequent (37.7%), followed by types 2 (19.3%), 4 (8.8%) and 3 (7.9%). Types 5 and 6 were the least prevalent (3.5%). Ten samples (8.8%) revealed mixed infections: type 1 was detectable in all and the co-infecting HCV types were types 2, 3 and 4 in 3, 4 and 3 cases, respectively. These results suggest that the serotyping assay as an alternative method of distinguishing the major types of HCV, also for particular risk groups and especially in laboratories that lack the specific expertise to perform genotyping methods. Age-related differences in patients with type 5 compared with those with types 3 and 6 may provide evidence of a more recent spread of these latter types.

Correlation of serum hepatitis C virus RNA titre with aminotransferases and liver histopathological findings in HCV-seropositive cases with end-stage chronic liver disease

The quantity of circulating hepatitis C virus (HCV) RNA, aminotransferases and the degree of liver cell injury in relation to HCV serotype have not been fully studied. In this work, we estimated the HCV RNA titre in serum and correlated the findings with levels of aminotransferases, gamma glutamyltransferase (GGT), and liver histopathological changes and with HCV serotype. HCV RNA was found in 22 out of 30 HCV-seropositive cases included in this study (73.3%) and serotype 4 represented 90.9% (20/22). Levels of aminotransferases and GGT correlated with the levels of serum HCV RNA. Noticeably, GGT showed the highest positive correlation with the level of HCV RNA. Liver histopathological findings of 15 patients showed that eight had hepatocellular carcinoma and seven had cirrhosis. There was no significant difference between these two groups regarding levels of enzymes or serum HCV RNA titre.

Presence of multiple genotype-specific antibodies in patients with persistent infection with hepatitis C virus (HCV) of a single genotype: evidence for transient or occult superinfection with HCV of different genotypes.

We investigated the significance of multiple genotype-specific antibodies in patients with persistent infection with hepatitis C virus (HCV) of a single genotype. Titers of genotype-specific antibodies to group 1 and 2 HCV polypeptides in the NS4 region of HCV were measured in 53 hemophiliacs and 58 nonhemophiliacs who were persistently infected with HCV of a single genotype. In addition, sequence variability in hypervariable region 1 (HVR1) of HCV was evaluated in these patients. The presence of antibodies to both group 1 and 2 polypeptides, reflecting a mixture of serotypes, was more frequent in hemophiliacs (11 of 53 patients, 20.8%) than in nonhemophiliacs (two of 58 patients, 3.4%; p = 0.01). HVR1 sequence variability in 13 patients with mixed serotypes was higher than in 87 patients with a single serotype (21.1 +/- 4.3% vs 8.5 +/- 6.3%; p < 0.01). A mixture of HCV serotypes was more common in hemophiliacs with persistent HCV infection of a single genotype who were at high risk of exposure to HCV than in nonhemophiliacs, and the sequence variability of the infecting strains was high in these patients. These data are suggestive of the effects of superinfection with HCV of different genotypes. The presence of multiple genotype-specific antibodies to HCV may be evidence of transient or occult superinfection with HCV of different genotypes in patients with persistent infection by HCV of a single genotype.

Presence of multiple genotype-specific antibodies in patients with persistent infection with hepatitis C virus (HCV) of a single genotype: evidence for transient or occult superinfection with HCV of different genotypes

OBJECTIVE: We investigated the significance of multiple genotype-specific antibodies in patients with persistent infection with hepatitis C virus (HCV) of a single genotype. METHODS: Titers of genotype-specific antibodies to group 1 and 2 HCV polypeptides in the NS4 region of HCV were measured in 53 hemophiliacs and 58 nonhemophiliacs who were persistently infected with HCV of a single genotype. In addition, sequence variability in hypervariable region 1 (HVR1) of HCV was evaluated in these patients. RESULTS: The presence of antibodies to both group 1 and 2 polypeptides, reflecting a mixture of serotypes, was more frequent in hemophiliacs (11 of 53 patients, 20.8%) than in nonhemophiliacs (two of 58 patients, 3.4%; p = 0.01). HVR1 sequence variability in 13 patients with mixed serotypes was higher than in 87 patients with a single serotype (21.1 ± 4.3% vs 8.5 ± 6.3%; p < 0.01). CONCLUSIONS: A mixture of HCV serotypes was more common in hemophiliacs with persistent HCV infection of a single genotype who were at high risk of exposure to HCV than in nonhemophiliacs, and the sequence variability of the infecting strains was high in these patients. These data are suggestive of the effects of superinfection with HCV of different genotypes. The presence of multiple genotype-specific antibodies to HCV may be evidence of transient or occult superinfection with HCV of different genotypes in patients with persistent infection by HCV of a single genotype.

Enzyme-linked immunosorbent assay to detect hepatitis C virus serological groups 1 to 6.

By conventional serological grouping methods, it is possible to determine hepatitis C virus (HCV) serological groups for genotypes 1a, and 1b, and genotypes 2a, and 2b, but not for other genotypes, i.e., 3a, 3b, 4a, 5a, and 6a. In this study, we attempted to serologically group HCV with the Murex HCV serotyping 1 to 6 assay (Murex Diagnostics, Kent, UK), using an enzyme-linked immunosorbent assay (ELISA) based on genotype-specific peptides from the NS4 region. The subjects of this study were 365 patients infected with HCV of genotype 1a, 1b, 2a, 2b, 3a, or 3b. The sensitivity of the assay was 100% in patients with genotype 1a, 82.7% in those with 1b, 68.5% in those with 2a, 84.2% in those with 2b, 50.0% in those with 3a, and 76.5% in those with genotype 3b. The overall sensitivity was 78.4%. The specificity of the assay was 100% in the subjects with genotype 1a, 98.8% in those with 1b, 98.4% in those with 2a, 96.9% in those with 2b, 100% in those with 3a, and 100% in those with genotype 3b. The overall specificity was 98.6%. The concordance of the assay was 100% in subjects with genotype la, 81.7% in those with 1b, 67.4% in those with 2a, 81.6% in those with 2b, 50.0% in those with 3a, and 76.5% in those with genotype 3b. The overall concordance was 77.5%. We believe it would be better to serotype with the Murex HCV serotyping 1 to 6 assay, if other than serological group (Gr) 1 or Gr 2 is suspected in particular ethnic groups or in subjects with an indeterminate result with the Immucheck HCV Gr assay (Kokusai, Kobe, Japan), assuming that the genotype must be other than 1a, 1b, 2a, or 2b.

Large-scale analysis of hepatitis C virus serological typing assay: effectiveness and limits.

The HCV (hepatitis C virus) Serotyping 1-6 Assay (Murex Laboratories) was evaluated on 303 French HCV-infected patients. Serological typing results were compared to the genotypes obtained from sequence analyses of the 5' noncoding regions of the virus genome from 46 HCV-infected patients, and assay specificity was found to be high (97.6%). The serological typing assay, run in 257 consecutive HCV-infected patients, yielded an assay sensitivity lower (70.6%) than that previously reported. This finding was attributed mainly to nonreactive sera from human immunodeficiency virus (HIV)-positive patients (P < 0.001) and perhaps reflected cryoglobulin positivity in others. No anti-type 6 reactivity was detected, and the overall serological type distribution values for types 1 to 5 were 67.3, 7.9, 16.4, 6.6, and 0.9%, respectively. A higher prevalence of type 4 was noted among HIV-infected patients (P < 0.001). In addition, serotype 2 was significantly more frequent in cryoglobulinemia positive than in cryoglobulinemia-negative patients (P < 0.05). Although an initial high level (7%) of mixed serological typing reactivities was found, after predilution of serum only two mixed infections could be confirmed (0.9%). It is suggested, therefore, that mixed reactivities have to be interpreted carefully and retested with prediluted serum, particularly when the optical density of the reactivity is > 2.5 or remains > 0.4 after competition with all type-specific peptides. The high specificity and relatively good sensitivity even in immunocompromised patients obtained with this assay indicate that it can be used routinely. Because response to treatment is linked to HCV type, this assay could be used to identify HCV serotype to guide therapeutic decisions.

Genes of the major histocompatibility complex class II influence the outcome of hepatitis C virus infection

BACKGROUND & AIMS: The host's immune response may influence the course of hepatitis C virus (HCV) infection. The aim of this study was to investigate the distribution of HLA class II alleles in white subjects who spontaneously recovered from HCV infection compared with that in patients with persistent infection.METHODS: HLA-DRB1 and -DQB1 typing were performed in 103 consecutive patients with persistent HCV infection (HCV antibody positive, HCV RNA positive) and in 25 subjects with transient HCV infection (HCV antibody positive, persistently negative HCV RNA).RESULTS: No significant differences between subjects with transient or persistent infection were observed for age, sex, source of infection, or HCV serotype. The frequency of DQB1*0301 and DRB1*1101 alleles was higher in patients with transient infection than in those with persistent infection (84% vs. 30.8%, 40% vs. 9.8%; P < 0.01 and P < 0.02, respectively [Bonferroni correction]). DRB1 and DQB1 alleles did not influence viral load as an independent factor. Mean Knodell's scores were lower in patients with DQB1*0301 allele (6.12 +/- 0.4) than in those negative for DQB1*0301 (7.37 +/- 0.3; P < 0.05).CONCLUSIONS: Our results suggest that host- rather than virus-related factors are probably involved in the spontaneous clearance of HCV.(Gastroenterology 1997 Nov;113(5):1675-81)

Predictors of the efficacy of interferon therapy in chronic hepatitis C virus infection. Tokyo-Chiba Hepatitis Research Group

BACKGROUND & AIMS: The relative role of virus load and hepatitis C virus (HCV) subtype as predictor of the efficacy of interferon (IFN) therapy is still in dispute. To resolve this issue, a multicenter, randomized, prospective study of 272 patients with chronic hepatitis C but without cirrhosis was conducted.METHODS: The patients were randomly assigned to two different dose groups: 6 million units (MU) or 9 MU IFN three times a week for 6 months. Serum HCV RNA levels and HCV subtypes were determined.RESULTS: HCV RNA negativity rate at the completion of treatment with 9 MU IFN was higher than that with 6 MU (75% vs. 44%; P < 0.05). Virus eradication at 12 months after completion of treatment was higher in the 9 MU group than in the 6 MU group (36% vs. 25%; P < 0.05), especially in patients who had an intermediate virus load (10(4)-10(5) copies/mL by Amplicor monitor assay) (52% vs. 19%; P = 0.029). Virus eradication rate in patients with serotype 2 was higher than in those with serotype 1 for both regimens (6 MU, 53% vs. 15%; 9 MU, 76% vs. 29%; each P < 0.05).CONCLUSIONS: This prospective study showed that virus load, HCV serotype, and IFN dose are important predictors of the virological response to IFN therapy but virus load is the most important factor influencing the efficacy of IFN.(Gastroenterology 1997 Aug;113(2):558-66)

Serological determination of hepatitis C virus genotype: comparison with a standardized genotyping assay

In patients with chronic hepatitis C, determination of hepatitis C virus (HCV) genotype could be routinely run in the future to tailor treatment schedules. The suitabilities of two versions of a serological, so-called serotyping assay (Murex HCV Serotyping Assay version 1-3 [SA1-3] and Murex HCV Serotyping Assay version 1-6 [SA1-6]; Murex Diagnostics Ltd.), based on the detection of genotype-specific antibodies directed to epitopes encoded by the NS4 region of the genome, for the routine determination of HCV genotypes were studied. The results were compared with those of a molecular biology-based genotyping method (HCV Line Probe Assay [INNO-LiPA HCV]; Innogenetics S.A.), based on hybridization of PCR products onto genotype-specific probes designed in the 5' noncoding region of the genome, obtained with pretreatment serum samples from 88 patients with chronic hepatitis C eligible for interferon therapy. Definitive genotyping was performed by sequence analysis of three regions of the viral genome in all samples with discrepant typing results found among at least two of the three assays studied. In all instances, sequence analysis confirmed the result of the INNO-LiPA HCV test. The sensitivity of SA1-3 was 75% relative to the results obtained by the genotyping assay. The results were concordant with those of genotyping for 92% of the samples typeable by SA1-3. The sensitivity of SA1-6 was 89% relative to the results obtained by the genotyping assay. The results were concordant with those of genotyping for 94% of the samples typeable by SA1-6. Overall, SA1-6 had increased sensitivity relative to SA1-3 but remained less sensitive than the genotyping assay on the basis of PCR amplification of HCV RNA. Cross-reactivities between different HCV genotypes could be responsible for the mistyping of 8 (SA1-3) and 6% (SA1-6) of the samples. Subtyping of 1a and 1b is still not possible with the existing peptides, but discriminating between subtypes may not be necessary for routine use.

Severity of liver disease in liver transplantation recipients with hepatitis C virus infection: Relationship to genotype and level of viremia

Infection with hepatitis C virus (HCV) genotype 1b has been reported to be associated with more severe posttransplantation liver disease than infection with non-1b genotypes. To address this issue, we evaluated the outcome in 124 patients who underwent liver transplantation for chronic HCV infection. The HCV genotype and/or serotype responsible for infection was determined by four different methods. HCV RNA was detected in serum samples by polymerase chain reaction (PCR) amplification, and quantified by branched DNA assay. Disease severity was expressed as a histological score (which included grading of portal inflammation, lobular activity, fibrosis, and cytopathic changes). Median duration of histological follow-up was 25 months (range 1-75 months). Genotype was assignable in 112 (92.5%) patients. Genotypes responsible for infection were as follows: 1a = 32.2%, 1b = 27.3%, 2a = 7.4%, 2b = 8.3%, 3a = 14%, and mixed infection (more than one subtype) = 3.3%. Level of viremia, alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and total histological score were not significantly different in patients infected with type 1b compared with patients infected with other genotypes. While duration of histological follow-up was greater in patients infected with type lb versus other types (P = .02), by univariate and multivariate analysis neither HCV genotype (lb versus others), level of viremia nor duration of histological follow-up were associated with disease severity. Moreover, there was no significant difference in the actuarial graft survival in patients infected with type lb compared with that of patients infected with non-lb types (82% and 87% at 3 years, respectively). Reanalysis using HCV genotype 1 showed no association with disease severity, graft survival, and patient survival. We conclude that HCV genotype 1 and subtype 1b are not associated with disease severity or graft survival in liver transplantation recipients. (Hepatology 1996 Nov;24(5):1041-6)

Severity of liver disease in liver transplantation recipients with hepatitis C virus infection: relationship to genotype and level of viremia.

Infection with hepatitis C virus (HCV) genotype 1b has been reported to be associated with more severe posttransplantation liver disease than infection with non-1b genotypes. To address this issue, we evaluated the outcome in 124 patients who underwent liver transplantation for chronic HCV infection. The HCV genotype and/or serotype responsible for infection was determined by four different methods. HCV RNA was detected in serum samples by polymerase chain reaction (PCR) amplification, and quantified by branched DNA assay. Disease severity was expressed as a histological score (which included grading of portal inflammation, lobular activity, fibrosis, and cytopathic changes). Median duration of histological follow-up was 25 months (range 1-75 months). Genotype was assignable in 112 (92.5%) patients. Genotypes responsible for infection were as follows: 1a = 32.2%, 1b = 27.3%, 2a = 7.4%, 2b = 8.3%, 3a = 14%, and mixed infection (more than one subtype) = 3.3%. Level of viremia, alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and total histological score were not significantly different in patients infected with type 1b compared with patients infected with other genotypes. While duration of histological follow-up was greater in patients infected with type lb versus other types (P = .02), by univariate and multivariate analysis neither HCV genotype (lb versus others), level of viremia nor duration of histological follow-up were associated with disease severity. Moreover, there was no significant difference in the actuarial graft survival in patients infected with type lb compared with that of patients infected with non-lb types (82% and 87% at 3 years, respectively). Reanalysis using HCV genotype 1 showed no association with disease severity, graft survival, and patient survival. We conclude that HCV genotype 1 and subtype 1b are not associated with disease severity or graft survival in liver transplantation recipients.