Epidemiological, clinical and therapeutic associations of hepatitis C types in western European patients

Do differences exist between chronic hepatitis C genotypes 2 and 3?

INTRODUCTION

Six genotypes of the hepatitis C virus (HCV) have been identified thus far, and their distribution is well defined. Genotype 1, which is the most prevalent worldwide, is always compared to genotypes 2 and 3, particularly in terms of treatment response. However, little is known about the differences between genotypes 2 and 3 because these genotypes are analyzed together in most studies. Therefore, the aim of this study was to evaluate differences in the clinical, epidemiological, laboratory, and histological parameters between HCV-2 and HCV-3.

METHODS

Patients with chronic hepatitis C infected with genotypes 2 and 3 were studied retrospectively and compared according to clinical, laboratory, and histological aspects. Hepatitis C virus-ribonucleic acid (HCV-RNA) was analyzed quantitatively by TaqMan® real-time PCR, and the HCV genotype was determined by sequencing the 5'-untranslated region.

RESULTS

A total of 306 patients with chronic HCV-2 (n=50) and HCV-3 (n = 256) were studied. Subtype 2b (n=17/50) and subtype 3a (n=244/256) were the most prevalent among patients infected with HCV-2 and HCV-3, respectively. The mean age was 47 ± 10 years, and there was a predominance of men in the group studied (61%). Comparative analysis between HCV-2 and HCV-3 showed a younger age (p=0.002), less prevalence of arterial hypertension (p=0.03), higher serum albumin levels (p=0.01), more advanced stage of liver fibrosis (p=0.03), and higher frequency of steatosis in patients with HCV-3 (p=0.001). After multivariate regression analysis, all the variables, except serum albumin, remained as variables associated with HCV-3 in the final model.

CONCLUSIONS

Clinical and histological differences exist between HCV-2 and HVC-3, which suggests the need for separate analyses of these genotypes.

Neurological complications of hepatitis C infection

Though well-known as a cause of liver disease, Hepatitis C virus infection is emerging as a cause of a variety of peripheral and central nervous system disorders. The virus causes chronic persistent infection with complex immune responses in the majority of individuals. Viral infection may have the potential to generate neurological illness through direct infection of neural cells or through immune-mediated mechanisms, including enhancement of autoimmune responses. Moreover, the mainstay of antiviral treatment of hepatitis C infection, interferon-alpha, is itself associated with neurological morbidity. Thus neurologists are increasingly faced with diagnosing or even predicting a wide spectrum of neurological complications of hepatitis C infection and/or its treatment.

Temporal changes in HCV genotype distribution in three different high risk populations in San Francisco, California

Background

Hepatitis C virus (HCV) genotype (GT) has become an important measure in the diagnosis and monitoring of HCV infection treatment. In the United States (U.S.) HCV GT 1 is reported as the most common infecting GT among chronically infected patients. In Europe, however, recent studies have suggested that the epidemiology of HCV GTs is changing.

Methods

We assessed HCV GT distribution in 460 patients from three HCV-infected high risk populations in San Francisco, and examined patterns by birth cohort to assess temporal trends. Multiple logistic regression was used to assess factors independently associated with GT 1 infection compared to other GTs (2, 3, and 4).

Results

Overall, GT 1 was predominant (72.4%), however younger injection drug users (IDU) had a lower proportion of GT 1 infections (54.7%) compared to older IDU and HIV-infected patients (80.5% and 76.6%, respectively). Analysis by birth cohort showed increasing proportions of non-GT 1 infections associated with year of birth: birth before 1970 was independently associated with higher adjusted odds of GT 1: AOR 2.03 (95% CI: 1.23, 3.34). African-Americans as compared to whites also had higher adjusted odds of GT 1 infection (AOR: 3.37; 95% CI: 1.89, 5.99).

Conclusions

Although, HCV GT 1 remains the most prevalent GT, especially among older groups, changes in GT distribution could have significant implications for how HCV might be controlled on a population level and treated on an individual level.

An overview of HCV molecular biology, replication and immune responses

Hepatitis C virus (HCV) causes acute and chronic hepatitis which can eventually lead to permanent liver damage, hepatocellular carcinoma and death. Currently, there is no vaccine available for prevention of HCV infection due to high degree of strain variation. The current treatment of care, Pegylated interferon α in combination with ribavirin is costly, has significant side effects and fails to cure about half of all infections. In this review, we summarize molecular virology, replication and immune responses against HCV and discussed how HCV escape from adaptive and humoral immune responses. This advance knowledge will be helpful for development of vaccine against HCV and discovery of new medicines both from synthetic chemistry and natural sources.

Liver disorders in the elderly

Although there are no specific age-related liver diseases, it is increasingly recognized that the percentage and the actual number of elderly will increase substantially over the next twenty years. Moreover, the developments of new emerging conditions (e.g. non-alcoholic steatohepatitis) and novel therapeutic approaches have provoked increasing enthusiasm among hepatologists. Some liver diseases are particularly frequent in the elderly, e.g. chronic hepatitis C and hepatocellular carcinoma. The clinical course and management of liver disease in the elderly may differ in several aspects from those of younger adults. The problem of whether to offer antiviral treatment to a wide range of patients with chronic hepatitis C has arisen over the last eight to ten years, since the reduction in the risk of hepatocellular carcinoma was analyzed. Selected patients aged 65 and older have a chance of treatment with pegylated interferon plus ribavirin, despite a higher likelihood of side effects. The diagnosis of autoimmune hepatitis should be suspected in a patient over 65 years of age in case of 'acute' presentation with 10-fold increase in transaminases, jaundice and hyper-gammaglobulinemia, to avoid any delay in starting immunosuppressive therapy. The age of an end stage liver disease will increase over the next years, thus we will expects an increasing number of decompensated liver disease and hepatocellular carcinomas.

Modelling the past, current and future HCV burden in France: detailed analysis and perspectives

Two national HCV projections have been published in France which assumed that a part of observed hepatocellular carcinoma (HCC) deaths is a consequence of HCV epidemic. They applied the back-calculation method, in combination with a Markov model, to reconstruct the past history of HCV infection and then to predict HCV-related mortality. A preliminary model was first developed in the absence of effective therapy. It allowed testing many assumptions to model HCV natural history that were compatible with observed incidence of HCV-related HCC deaths. This model was then updated to take into account the availability of treatment and more recent epidemiological data. These two models are described in detail and results are discussed with a view to addressing the models' limitations. The models offered a useful tool to assess public health policy scenarios in planning healthcare responses to the HCV epidemic.

Peginterferon alfa-2b and ribavirin combination therapy for chronic hepatitis C

Pegylated interferon and ribavirin have been the standard treatment for chronic hepatitis C (CHC) since 2001. In the USA, hepatitis C is the most common blood-borne infection and the leading cause of cirrhosis requiring liver transplantation. Due to heightened awareness, more patients are being screened and diagnosed with CHC. Interferon-based therapy will continue to be a mainstay of treatment for years to come. A familiarity with the drugs used for the treatment of CHC is beneficial for most healthcare providers. This article will discuss the use of peginterferon alfa-2b and ribavirin, including dosing, length of treatment, mechanism of action, pharmacodynamics, pharmacokinetics, side effects, monitoring and contraindications, and will provide a future perspective on the treatment of CHC.

Epidemic dynamics of two coexisting hepatitis C virus subtypes

Hepatitis C virus (HCV) infection affects about 3% of the human population. Phylogenetic analyses have grouped its variants into six major genotypes, which have a star-like distribution and several minor subtypes. The most abundant genotype in Europe is the so-called genotype 1, with two prevalent subtypes, 1a and 1b. In order to explain the higher prevalence of subtype 1b over 1a, a large-scale sequence analysis (100 virus clones) has been carried out over 25 patients of both subtypes in two regions of the HCV genome: one comprising hypervariable region 1 and another including the interferon sensitivity-determining region. Neither polymorphism analysis nor molecular variance analysis (attending to intra- and intersubtype differences, age, sex and previous history of antiviral treatment) was able to show any particular difference between subtypes that might account for their different prevalence. Only the demographic history of the populations carrying both subtypes and analysis of molecular variance (AMOVA) for risk practice suggested that the route of transmission may be the most important factor to explain the observed difference.

Hepatitis C virus infection in a resident elderly population: a 10-year follow-up study

BACKGROUND

The natural history of hepatitis C virus infection in the elderly is poorly known.

OBJECTIVE

To assess the mortality rate, the progression of liver disease, the hepatitis C virus carrier state and the co-morbidity in a cohort of 35 out of 1,063 anti-hepatitis C virus positive elderly people prospectively followed-up from 1992 to 2002.

METHODS

Liver function tests, hepatitis C virus-RNA analysis, hepatitis C virus genotyping and abdominal ultrasonography were assessed at the beginning of the study, and then, liver function tests and ultrasonography were performed annually during the first 5 years of the follow-up. At the end of the 10-year period, causes of death were recorded, while surviving patients underwent again medical examination, liver function tests and abdominal ultrasonography.

RESULTS

Out of 35 patients with a 10-year follow-up, 12 patients died: only 2 (5.7%) from liver-related disease (hepatocellular carcinoma and liver failure), whilst 10 (28.5%) from extrahepatic causes. Out of the two patients dying from liver-related causes, one was hepatitis C virus-RNA positive and one hepatitis C virus-RNA negative. Among the 23 living patients, 13 were hepatitis C virus-RNA positive (56.5%), the majority being infected with genotype 2 (69%); of them, 6 (46.1%) had persistently normal alanine aminotransferase levels. None of the hepatitis C virus-RNA positive individuals had excessive alcohol intake.

CONCLUSION

Despite the presumably long duration of infection in our cohort, the liver-related mortality was five-fold lower than that from extrahepatic causes (five-fold higher). Lack of hepatic co-morbidity factors, such as alcohol consumption, seems to be relevant for the limited severity of liver disease.

Hepatitis C virus (HCV) 5′NC sequence variants and their association with hepatitis C risk groups

BACKGROUND

Genotype distribution of hepatitis C virus (HCV) is relatively uniform in Prague, Czech Republic. Unlike the other developed countries where HCV genotype 3 is increasingly associated with injection drug users (IDU), subtype 1b remains the most prevalent HCV subtype in Prague, regardless of risk factors.

OBJECTIVE

We wished to determine if subtype 1b strains could be further differentiated by comparing the conserved 5'NC sequences of the strains infecting IDU and non-IDU populations.

STUDY DESIGN

All prospectively collected serum samples that were HCV RNA positive were genotyped according to the 5'NC and NS5b regions. All 5'NC sequences were further analyzed for new mutations and these data were compared to patient epidemiologic information.

RESULTS

We found eight 5'NC sequence variants among 96 specimens tested. Further analysis of subtype 1b strains showed that a variant with a nucleotide insertion at -138 positions was found only among non-IDU subjects, while the variant with T-->C substitution at -94 was found only among the IDUs.

CONCLUSIONS

These observations suggest that the current HCV transmission between the IDU and non-IDU populations is uncommon, and may reflect the beginning of divergence of HCV genotypes in the IDU population in Prague.

New combination test for hepatitis C virus genotype and viral load determination using Amplicor GT HCV MONITOR test v2.0

AIM: To develop a new sensitive and inexpensive hepatitis C virus (HCV) combination test (HCV Guideline test) that enables the determination of HCV genotypes 1, 2 and 3, and simultaneous determination of HCV viral load using commercial Amplicor GT HCV MONITOR test v2.0 (microwell version).

METHODS: The HCV Guideline test used the PCR product generated in commercial Amplicor GT HCV Monitor test v2.0 for viral load measurement using microwell plate version of Amplicor HCV Monitor and also captured on separate plates containing capture probes and competitive oligonucleotide probes specific for HCV genotypes 1, 2 and 3, The HCV genotype was subsequently determined using the biotin-labeled PCR product and five biotin-labeled HCV-specific probes.

RESULTS: The sensitivity of the HCV Guideline test was 0.5 KIU/mL. Specificity of the HCV Guideline test was confirmed by direct sequencing of HCV core region and molecular evolutionary analyses based on a panel of 31 samples. The comparison of the HCV Guideline test and an in-house HCV core genotyping assay using 252 samples from chronic hepatitis C patients indicated concordant results for 97.2% of samples (59.5% genotype 1, 33.7% genotype 2, 6.0% genotype 3, and 0.8% mixed genotypes). Similarly, the HCV Guideline test showed concordance with a serological test, and the serological test failed to assign any serotype in 12.7% of the samples, indicating a better sensitivity of the HCV Guideline test.

CONCLUSION: Clinically, both viral load and genotypes (1, 2 and 3) have been found to be major predictors of antiviral therapy outcome regarding chronic hepatitis C based on guidelines and they are, in normal circumstances, performed as separate stand-alone assays. The HCV Guideline test is a useful method for screening large cohorts in a routine clinical setting for determining the treatment regimen and for predicting the outcome of antiviral therapy of chronic hepatitis C.

Phylogenetic analysis of hepatitis C virus isolates indicates a unique pattern of endemic infection in Cameroon

Hepatitis C virus (HCV) is a blood-borne pathogen that poses a significant threat to public health worldwide. The genetic diversity and distribution of HCV genotypes in non-Western countries, particularly subSaharan Africa, is poorly documented. This study reports a phylogenetic analysis of core and NS5B gene sequences of 37 HCV strains sampled in Cameroon. A high level of genetic diversity of both genotypes 1 and 4 was found, indicating a unique pattern of long-term HCV infection that has not been observed elsewhere. These results lead to the hypothesis that these HCV genotypes originated and diversified in west Central Africa before spreading to other regions.

Influence of age and date of infection on distribution of hepatitis C virus genotypes and fibrosis stage

The objective of this study was to assess the influence of age and date of acquisition of hepatitis C virus (HCV) infection on the distribution of genotypes and the progression of fibrosis in HCV-infected patients who were born in Spain and had their habitual place of residence in this country. Genotypic analysis was performed in 375 patients in whom it was possible to establish the year of HCV infection because the mode of transmission was known (transfusion, injection drug use, blood donor, or epidemic outbreak). In 298 patients with liver biopsy, fibrosis stage was related to age at infection, duration of infection, alcohol consumption, and HCV genotype. HCV subtype 1b was almost exclusively detected among transfusion recipients, but the onset of intravenous drug addiction was associated with the introduction of HCV genotypes other than 1b among injecting users with subsequent spread to other exposure risk groups. Fibrosis progression was influenced by alcohol consumption, increased duration of infection, and older age at infection. In summary, spread of intravenous drug use determined HCV infection by genotypes other than 1b. The risk of fibrosis progression was influenced more by age at viral acquisition and alcohol consumption than by the infecting genotype.

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.

The cutaneous manifestations of viral hepatitis

Viral hepatitis is a common disease with significant morbidity and mortality that is found throughout the world. It is a known cause of acute and chronic liver disease. Because the disease can be asymptomatic in its acute stages, the diagnosis is often missed. This article reviews the extrahepatic manifestations of the disease, in particular the visible cutaneous lesions, which offer clues to the diagnosis of viral hepatitis. Familiarity with the most common skin lesions associated with each type of hepatitis virus will be useful in identifying previously undiagnosed individuals. This article serves as a review of the most widely published associations between skin diseases and specific subtypes of viral hepatitis.

Immunopathogenesis of hepatitis C virus infection

Hepatitis C virus, a recently identified member of the family Flaviviridae, is an important cause of chronic viral hepatitis and cirrhosis. There are similarities in the nature of the immune response to this pathogen with immunity in other flavivirus and hepatotropic virus infections, such as hepatitis B. However, the high rate of viral persistence after primary hepatitis C infection, and the observation that neutralizing antibodies are not protective, would suggest that there are a number of important differences between hepatitis C, other flaviviruses, and hepatitis B. The phenomenon of quasispecies evolution and other viral factors have been proposed to contribute to immune evasion by hepatitis C virus. In the face of established persistent infection, virus-specific cytotoxic T lymphocytes may exert some control over viral replication. However, these same effectors may also be responsible for the progressive liver damage characteristic of chronic hepatitis C infection. The nature of protective immunity, including the role of innate immune responses early after hepatitis C exposure, remains to be defined.

Liver iron accumulation in chronic hepatitis C patients without HFE mutations: relationships with histological damage, viral load and genotype and alpha-glutathione S-transferase levels

BACKGROUND

Host and viral factors have been suggested as possible causative factors for the presence of liver iron accumulation in chronic hepatitis C. However, there is no agreement regarding the influence of liver iron accumulation on the biochemical and histological severity of chronic hepatitis C. Moreover, data concerning the relationships between both viral load and genotype and liver iron accumulation are scanty.

AIMS

To evaluate the biochemical, histological and virological assessment of a group of chronic hepatitis C patients without risk factors for iron overload, on the basis of the presence, degree and distribution of liver iron accumulation.

METHODS

Fifty-three chronic hepatitis C patients (34 men, 19 women; age 44 +/- 11 years) with no risk factors for liver iron accumulation and showing no HFE mutations were chosen from a broader cohort of chronic hepatitis C patients. The presence, degree and distribution of liver iron accumulation were assessed using Deugnier's score. Relationships between the presence of liver iron accumulation and grading and staging were carried out separately. Hepatitis C virus RNA serum levels and viral genotype were compared in patients with or without liver iron accumulation. Alpha glutathione S-transferase serum levels were assessed in all patients.

RESULTS

Overall, liver iron accumulation was mild and was present in 19 patients (36%). It was associated with male gender (P = 0.0358), and was reflected by high serum iron levels (P = 0.001) and high ferritin levels (P < 0.0001). Hepatitis C virus RNA levels and genotype were not associated with the presence of liver iron accumulation. In multivariate analysis, ferritin was the only variable significantly associated with liver iron accumulation (P < 0.0001). Grading was higher in patients with liver iron accumulation regardless of the site of iron deposition. Fibrosis was present in all patients with iron overload; these patients were more frequently cirrhotic. Moreover, patients with mesenchymal or mixed deposition had higher staging than patients with hepatocytic or no iron deposition. This feature was reflected by higher alpha-glutathione S-transferase levels.

CONCLUSIONS

Liver iron accumulation is mild in chronic hepatitis C patients without HFE mutations and is mainly reflected by serum ferritin levels. Viral characteristics do not seem to play a role in iron deposition. Liver iron accumulation is associated with higher grading, advanced fibrosis and cirrhosis. Moreover, higher staging is associated with mesenchymal or mixed iron deposition. In these patients, higher alpha-glutathione S-transferase levels seem to reflect more complex damage.

Serum HCV RNA levels correlate with histological liver damage and concur with steatosis in progression of chronic hepatitis C

The role of HCV RNA levels and host factors in the severity of liver injury was studied. Enrolled were 298 consecutive liver biopsy-proven chronic hepatitis (CH) C patients (179 men; median age: 52 years, range 19-68; CH, 198; cirrhosis, 100) and 18 chronic hepatitis C with normal ALT. HCV genotypes were: 1a, 4.3%; 1b, 53%; 2a/c, 28%; 3a, 7%; 4, 1.3%, and mixed 6.4%. Serum HCV RNA levels were similar for all genotypes (median: 2.8 x 10(6) eq/ml; range <0.2-69). In patients with chronic hepatitis without cirrhosis, the serum HCV RNA levels reflected the grade of liver necroinflammatory activity (R = 0.45; P < 0.001) and the stage of fibrosis (R = 0.51; P < 0.001), regardless of age, gender, HCV genotype, hepatic steatosis, and hepatic iron overload. Patients with high serum HCV RNA levels (> or =3 x 10(6) eq/ml) had higher ALT values (P < 0.002) than those with lower HCV RNA levels. Patients with normal ALT showed low HCV RNA levels (median: 0.82 x 10(6) eq/ml) and histological features of minimal or mild chronic hepatitis. Cirrhotic patients showed significantly lower levels of viremia than those with chronic hepatitis with a similar HAI. The data of a subgroup of 62 patients with an established time of infection showed that for a similar duration of disease, patients with serum HCV RNA levels > or =3 x 10(6) eq/ml had a significantly higher fibrosis score than those with lower levels. HAI and fibrosis score were significantly higher in patients with HCV RNA levels > or =3 x 10(6) eq/ml and grade 3-4 steatosis than those with lower HCV RNA levels and steatosis grades. The data indicate that the liver damage is correlated with the HCV RNA levels and that a high viral load acts together with steatosis in accelerating the progression of liver injury.

Nested restriction site-specific PCR to detect and type hepatitis C virus (HCV): a rapid method to distinguish HCV subtype 1b from other genotypes

Genotypic differentiation of hepatitis C virus (HCV) has become an integral part of clinical management and epidemiologic studies of hepatitis C infections. Thus, it is extremely important in areas such as the Czech Republic, where current instrumentation and kits for assessing HCV infection are too costly for widespread use. We describe a new and relatively inexpensive method called nested restriction site-specific PCR (RSS-PCR) that generates a "fingerprint" pattern to represent an HCV genotype without the use of restriction endonucleases and that specifically differentiates HCV genotype 1b from the other HCV genotypes. The RSS-PCR method was applied directly to serum samples from patients with hepatitis C from the Czech Republic and from patients with known HCV genotypes from the United States. The method was validated by comparison of the subtype determined by RSS-PCR to the subtype determined from analysis of the 5' noncoding region (NC) or the nonstructural protein gene (NS5b) nucleotide sequence of HCV in these clinical samples. From 75 Czech samples containing HCV RNA, three distinct RSS-PCR patterns were observed; 54 were predicted to contain subtype 1b, 19 were predicted to contain subtype 1a, and 2 were predicted to contain subtype 3a. Among 54 samples predicted to contain HCV genotype 1b, all were confirmed by their 5' NC or NS5b sequences to be subtype 1b. Thus, both the sensitivity and specificity of the RSS-PCR test for the differentiation of HCV subtype 1b from the others were 100%. While the assay described here was designed to specifically differentiate HCV subtype 1b from the other HCV genotypes, the RSS-PCR method can be modified to differentiate any HCV genotype or subtype of interest. Its simplicity and speed may provide new opportunities to study the epidemiology of HCV infections and the relationship between HCV genotypes and clinical outcome by more laboratories throughout the world.

Outcome of liver disease in a large cohort of histologically proven chronic hepatitis C: influence of HCV genotype

OBJECTIVE

To assess the influence of hepatitis C virus (HCV) genotypes on the clinical outcome of liver disease, we analysed 2,307 patients.

RESULTS

The most frequently represented genotypes were 1b (40%) and 2 (28.1%). Patients with these genotypes had a median age higher than patients with other genotypes (P< 0.01). The overall survival of subjects with genotype 1b was poorer than the survival of patients with other genotypes (P< 0.01). Liver cirrhosis was found in 280 patients (12.1%), and type 1b was the most represented isolate among them (P< 0.01). Sixty-two patients (22%) developed hepatocellular carcinoma (HCC) during a follow-up of 1481.8 cumulative years (estimated crude incidence rate, 4.1 cases per 100 person-years for all cirrhotics; 5.9 cases for genotype 1a; 4.5 cases for genotype 1b; and 2.8 cases for genotypes non-1). Considering the whole population of 2,307 patients, only genotype 1b was associated significantly with both cirrhosis and the development of HCC. One hundred and nineteen cirrhotic patients underwent treatment with interferon in uncontrolled studies. Interferon therapy was associated with both better survival (P< 0.01) and a lower cumulative hazard for HCC (P< 0.01).

CONCLUSIONS

Genotype 1b was associated with a poorer prognosis, probably because it leads to cirrhosis and consequently to HCC development. However, our data did not confirm genotype 1b as an independent risk factor for HCC in liver cirrhosis, which plays a major role in carcinogenesis. Interferon should be considered as a useful strategy in cirrhosis for improvement of survival and reduction of HCC risk.

The origin and evolution of hepatitis viruses in humans

The spread and origins of hepatitis C virus (HCV) in human populations have been the subject of extensive investigations, not least because of the importance this information would provide in predicting clinical outcomes and controlling spread of HCV in the future. However, in the absence of historical and archaeological records of infection, the evolution of HCV and other human hepatitis viruses can only be inferred indirectly from their epidemiology and by genetic analysis of contemporary virus populations. Some information on the history of the latter may be obtained by dating the time of divergence of various genotypes of HCV, hepatitis B virus (HBV) and the non-pathogenic hepatitis G virus (HGV)/GB virus-C (GBV-C). However, the relatively recent times predicted for the origin of these viruses fit poorly with their epidemiological distributions and the recent evidence for species-associated variants of HBV and HGV/GBV-C in a wide range of non-human primates. The apparent conservatism of viruses over long periods implied by these latter observations may be the result of constraints on sequence change peculiar to viruses with single-stranded genomes, or with overlapping reading frames. Large population sizes and intense selection pressures that optimize fitness may be the factors that set virus evolution apart from that of their hosts.

Hepatitis C virus: routes of infection and genotypes in a cohort of anti-HCV-positive French blood donors

BACKGROUND

We evaluated and analysed risk factors of HCV-infected blood donors according to HCV genotypes in order to improve the transfusion policy and safety of blood supply.

MATERIALS AND METHODS

HCV-RNA was analysed in sera from 518 anti-HCV-positive blood donors, who were invited to medical consultation and interview as to risk factors by means of an extensive questionnaire. HCV genotyping was done on all samples positive for HCV-RNA.

RESULTS

Of the 518 sera, 399 (77%) were HCV-RNA positive, and 394 of 399 HCV genotypes were identified. Major genotypes were 1b (34.3%), 3a (24%), 1a (19.5%) and 2 (11.4%). Of the donors, 289 (55.8%) were interviewed regarding their risk behaviour: 27% were former intravenous drug users (IVDUs), 26% had been transfused, 8% had a history of invasive diagnostic procedures, and 13% a history of surgery. Among the 224 interviewed donors, genotypes 1a and 3a were mainly associated with IVDU (51 and 45% respectively) and genotype 1b, with transfusion and nosocomial infections (40 and 25%, respectively).

CONCLUSION

In this population of anti-HCV-positive blood donors, nosocomial infection may be a route of HCV spread, but the main risk factor remains IVDU, particularly in young men. The transfusion policy will improve if predonation interviews of such young men are done with a specific and sensitive questionnaire.

HCV infection in northeastern Brazil: unexpected high prevalence of genotype 3a and absence of African genotypes

The genomic diversity of HCV embraces 6 genotypes and at least 52 subtypes with clinical and epidemiological correlations. There is a paucity of studies assessing HCV genotypes and biomolecular epidemiology in Brazil. We studied genotype distribution and epidemiological aspects in 232 HCV carriers, 133 (57.9%) males and 99 (42.1%) females, followed in the liver disease referral unit in Salvador, BA, northeastern Brazil. All of them were anti-HCV positive by 3rd generation ELISA assay, and HCV-RNA positive by RT-PCR. Genotyping was performed by INNOLIPA. Assessment of risk factors for HCV infection showed that 93 (40%) had past blood transfusion, 14 (6%) intravenous drug use, 19 (8%) inhalation of cocaine, 28 (12%) tattooing, 15 (7%) were health care workers, 5 (2%) had reused disposable syringes, 5 (2%) had multiple risk factors and in 53 (23%) no risk factor was determined. Genotype 1a was observed in 75 (32%), 1b in 72 (31%), 3a in 61 (26%), 2ab in 14 (6%); 5 (2.5%) had mixed genotypes and 5 (2.5%) were undetermined. Patients with genotype 1 had a higher mean age (P < 0.05) and no particular risk factors were associated with a specific genotype. Genotype 1 largely predominates in northeast Brazil followed by genotype 3 which, in this population, does not seem to be related to intravenous drug abuse, in contrast to some European studies. Although 80% of the Salvador population comprises African-Brazilians, no African genotype was identified, which may mean that HCV was introduced into this region via European immigration. This study demonstrated some peculiarities of HCV epidemiology in Brazil and strongly suggests that HCV introduction to this region was probably related to European immigration.

Molecular characterisation of HCV genotype 4 isolates circulating in Italy

The characteristics of genotype 4 subtype variability of HCV isolates circulating in Italy were studied. The viral isolates were identified from 736 HCV-RNA positive sera originated from seroepidemiological studies undertaken in 4 different regions of North, South Italy and Sardinia. 24 out of 28 genotype 4 isolates (86%) were classified by phylogenetic analysis of E1 genome region (915-1128) as belonging to subtype 4d (Neighbour Joining Method). Three isolates classified as subtype 4a were detected in haemophilic patients, possibly related to infections from blood products. One isolate classified as a new subtype derived from an Eritrean patient subjected to haemodialysis. Very high genome homogeneity (mean 4.3%) was shown by genetic comparisons (DNA dist programs Phylip Package) for all the 4d isolates relative to the studies performed in Veneto, Calabria and Sardinia and originated from subjects from the general population and outpatients (19 subtype 4d isolates out of 24). In the 3 studies different prevalence rates of HCV genotype 4 (3.1%, 1. 3%, 14% respectively) were found. In contrast a considerable degree of heterogeneity, both intragroup and with the other groups (mean 8. 2% and 8.7%, respectively) was observed among subtype 4d isolates identified in the patients of a haemodialysis centre in Apulia region. In conclusion the subtype 4d of genotype 4 was highly prevalent and endemic in Italy. An elevated level of viral heterogeneity was observed in one study carried out in a region of Southern Italy. This can be related to a longer period of past endemicity of this genotype and to a high level of exposure to reinfections in particular categories of patients such as haemodialysis patients.

Prevalence of antibodies against hepatitis C virus in the elderly: a seroepidemiological study in a nursing home and in an open population. The Collaborative Group

BACKGROUND

The prevalence of antibodies against hepatitis C virus (anti-HCV) increases in the general population with advancing age. Several discrepancies exist in the epidemiology of HCV, however, when selected elderly population groups are tested.

OBJECTIVE

To evaluate the HCV prevalence in two groups of elderly people living in the same geopgraphical area of northeast Italy, i.e., one including residents of a nursing home, the other including subjects living at home.

METHODS

The overall sample included 496 subjects (mean age 79.31 +/- 8.9 years); 288 were in a nursing home, and 208 were living at home. Enrollment in the latter group was based on all subjects over 65 years old listed under the public health service in the same district. The overall rate of adhesion to the study was 90%. Each subject was administered an anonymous questionnaire testing sociodemographic data and risk factors for HCV infection. Serological tests included: anti-HCV and hepatitis B virus serum markers. Multiple logistic regression analysis was performed to evaluate risk factors for anti-HCV positivity.

RESULTS

Anti-HCV positivity was found in 34 of 288 (11.8%) elderly in the nursing home and in 23 of 208 (11.1%) in the open population. When the total population was considered, females exhibited a significantly a higher prevalence of anti-HCV than males (13.4 vs. 7.5%, p < 0.05). In both males and females, the highers rate of anti-HCV prevalence was found among the 75- to 79-year-old subjects. A decline in anti-HCV prevalence was observed in the very old subjects (over 80 years of age). None of the anti-HCV-positive subjects was found to be coinfected with hepatitis B surface antigen. However, multiple logistic regression analysis identified the age group between 70 and 79 years, female gender, and positivity for antihepatitis B surface antigen and/or antihepatitis B core antigen as independent variables significantly associated with HCV prevalence.

CONCLUSIONS

The prevalence of anti-HCV proved identical among elderly people living in the nursing home or at home, suggesting that nursing homes do not represent a risk factor for HCV infections; the significant association between HCV prevalence and antihepatitis B surface antigen and/or antihepatitis B core antigen positivity supports a common route of transmission of the two viruses; these findings would suggest that there was an epidemic of HCV infection during the Second World War and in the years immediately afterwards.

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

OBJECTIVES

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.

DESIGN

Investigation of stored sera that were collected from injecting drug users in the 1970s and comparison with sera collected in the 1990s.

SETTING

Inner Sydney, 1974-1975 and 1994-1996.

PATIENTS

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).

MAIN OUTCOME MEASURES

HCV antibody prevalence (1970s); profile of HCV serotypes (1970s and 1990s); and serological evidence of hepatitis A and B.

RESULTS

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.

CONCLUSIONS

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.

Clinical significance of hepatitis C virus genotypes

On the basis of phylogenetic analysis of nucleotide sequences, multiple genotypes and subtypes of hepatitis C virus (HCV) have been identified. Characterization of these genetic groups is likely to facilitate and contribute to the development of an effective vaccine against infection with HCV. Differences among HCV genotypes in geographic distributions have provided investigators with an epidemiologic marker that can be used to trace the source of HCV infection in a given population. HCV genotype 1 may represent a more aggressive strain and one that is less likely to respond to interferon treatment than HCV genotype 2 or 3. However, these observations require confirmation before HCV genotyping can be used in clinical settings.

Clinical significance of hepatitis C virus genotypes

On the basis of phylogenetic analysis of nucleotide sequences, multiple genotypes and subtypes of hepatitis C virus (HCV) have been identified. Characterization of these genetic groups is likely to facilitate and contribute to the development of an effective vaccine against infection with HCV. Differences among HCV genotypes in geographic distributions have provided investigators with an epidemiologic marker that can be used to trace the source of HCV infection in a given population. HCV genotype 1 may represent a more aggressive strain and one that is less likely to respond to interferon treatment than HCV genotype 2 or 3. However, these observations require confirmation before HCV genotyping can be used in clinical settings.

HCV genotypes--role in pathogenesis of disease and response to therapy

Hepatitis C virus (HCV) shows considerable variation in its genomic structure, allowing classification into six main genotypes. Epidemiological studies have shown marked differences in genotype distribution by geographical region, and between patient groups. Improved understanding of the rate of nucleotide sequence mutation in HCV has allowed the approximate time of divergence of major genotypes to be estimated, and the origin and spread of the present epidemic of hepatitis C to be better defined. Improved methods of genotype definition over the last few years have enabled the importance of genotype in the progression of HCV-related disease and response to anti-viral therapy to be studied. Present data strongly indicates that HCV genotype is an important determinant of response to treatment, but the effect of genotype on disease progression has been harder to clarify. This is largely due to the absence of model systems of HCV infection, the epidemiological differences in patient groups infected with the different genotypes, and the lack of good prospective longitudinal clinical data. As a result of advances in methodology, and recent results of large clinical trials of combination therapy, a knowledge of HCV genotype is now central to the clinician in the management of patients with chronic hepatitis C.

Correlation of genotypes and route of transmission with histologic activity and disease stage in chronic hepatitis C

Our objective was to evaluate the histopathological features of chronic hepatitis C of 64 liver biopsies and to correlate this with the route of transmission of hepatitis C virus, the genotype of HCV, and the patient's age. Moderate chronic hepatitis was the most frequently observed (62.5%). Cirrhosis was observed in 14 patients (21.9%) and was more frequently found among patients over 40 years of age (34.3% vs. 6.9%, P = 0.025). The mean histopathological activity index (HAI) was significantly higher in the sporadic (10+/-3.1) than the posttransfusional (7.5+/-3.7) and the intravenous drug use (IVDU) groups (6.3+/-2.8) (P<0.02). Moreover the sporadic group showed more fibrosis (P<0.04) than the posttransfusional group. No liver cirrhosis was found in the IVDU group. The overall prevalence of HCV variants was: 54.7% type 1b, 4.6% type 1a, 37.5% type 2c, 1.6% type 2b, 1.6% type 2. The genotype distribution showed no relation to the HAI, hepatitis activity (grade), and fibrosis (stage) of the liver disease. In conclusion, the sporadic route of transmission of HCV was related to a more severe chronic hepatic disease, a finding that could influence future antiviral therapies. The predominance of HCV type 1b in this study reflects the higher frequency of this variant in our area. Our data suggests that the ultimate consequence of HCV chronic infection depends on patient age rather than on HCV genotype.

Predictors of a favorable response to alpha interferon therapy for hepatitis C

The most consistently identified predictive factors for a response to both IFN-alpha monotherapy and IFN-alpha in combination with ribavirin are a low HCV RNA level, the absence of fibrosis, infection with HCV genotype 2 and 3, and a prolonged duration of treatment. In addition, an early response to IFN-alpha predicts response to IFN-alpha monotherapy but not necessarily to combination therapy. There does not appear to be any major gain in treating IFN-naive patients with HCV genotype 2 or 3 infection with a combination of IFN-alpha and ribavirin for longer than 6 months. The identification of these predictive factors has allowed improvement in study design and assessment and may provide a patient with an idea of the likelihood of response, making possible a more informed decision regarding treatment. At present, none of these factors, either alone or in combination, completely predicts response to IFN-alpha. Thus, individual patients should not be denied treatment on the basis of these factors.

Late disappearance of hepatitis C virus RNA from peripheral blood mononuclear cells in patients with chronic hepatitis C in sustained response after alpha-interferon therapy

OBJECTIVE

We aimed to investigate the modifications of HCV RNA (genomic and antigenomic strands) in peripheral blood mononuclear cells (PBMCs) of long-term responder patients to alpha-interferon therapy, and their usefulness as criteria of definitive HCV eradication.

METHODS

We studied 10 patients with chronic hepatitis C with > 1 yr of sustained response after alpha-interferon therapy (normal alanine aminotransferase [ALT] and negative serum HCV RNA). Serum HCV RNA and genotyping were determined. Approximately 2 and 4 yr after completion of treatment we investigated the presence of HCV RNA (genomic and antigenomic strands) in PBMCs. Eight of 10 patients were rebiopsed 2 yr after discontinuation of treatment.

RESULTS

The mean follow-up was 46.6 +/- 4.6 months (range, 39-51 months). In this period, all patients remained in sustained response. In the first determination, all patients had HCV RNA genomic strands and two patients had antigenomic strands detectable in PBMCs. Two years later only two patients had genomic and none had antigenomic strands detectable. After 4 yr of sustained response, eight of 10 patients lost HCV RNA from PBMCs.

CONCLUSIONS

In the long-term follow-up, the majority of patients with chronic hepatitis C with sustained response after alpha-interferon therapy progressively lost HCV RNA from PBMCs. This determination in PBMCs is not a predictor of response.

Modeling the hepatitis C virus epidemic in France

A backcalculation approach allows a reconstruction of the history of hepatitis C virus (HCV) infection in France and predictions of mortality from hepatocellular carcinoma (HCC) related to the virus. The model uses information from the literature about the natural history of the disease, epidemiological data about infected subjects in three French cohorts, and mortality data from national statistics. It seeks to determine the annual transition probabilities from chronic hepatitis to cirrhosis and the HCV incidence per year in the past. These unknowns are found by fitting the observed deaths from HCC that are attributable to HCV. Optimal values for these unknowns then allow to project the number of HCC deaths attributable to HCV for each year through 2025 (for patients infected before 1996). The model traces the HCV epidemic in France back to around the 1940s. It predicts that HCC mortality related to HCV will continue to increase through 2020 in the absence of treatment, with a 150% increase in the yearly incidence among men and 200% among women. The model also confirms that progression to cirrhosis depends strongly on sex and age. At any age, the annual probability of progression is 10 times greater for men than for women. Moreover, for men aged between 61 and 70 years, this probability is 300 times greater than that for men aged between 21 and 40 years.

HCV genotypes in Northern Italy: a survey of 1368 histologically proven chronic hepatitis C patients

BACKGROUND/AIMS

Hepatitis C virus (HCV) easily undergoes genomic changes, thus accounting for the presence of different genotypes, with different geographic distributions and different outcomes of chronic hepatitis. Type 1b is frequently found in advanced diseases; however, since this genotype is the most prevalent in older patients, the association with advanced age and severity of the disease is confounding. The aim of this study was to assess changes in the prevalence of HCV genotypes by surveying a large population of chronic hepatitis C patients in Northern Italy, and to assess if the high prevalence of genotype 1b in older patients with advanced diseases simply reflects the duration of HCV infection, rather than intrinsic biological properties of HCV.

METHODS

We studied 1368 HCV-RNA positive patients, with histologically proven chronic hepatitis. Drug addiction, blood transfusions and sporadically acquired infections represented the risk factors.

RESULTS

Genotype 1b, the most prevalent isolate, and genotype 2a were associated with older age, cirrhosis, sporadically-acquired infections and blood transfusion, while types 1a, 3a, and 4 were associated with younger age, chronic persistent hepatitis and drug addiction. Patients with a history of transfusions were divided into four groups depending on the period of transfusion. The prevalence of genotype 1b decreased with time. Type 3a appeared only after 1979.

CONCLUSION

The severity of chronic hepatitis C could be related more to the duration of the infection rather than to the intrinsic pathogenicity of HCV genotypes.

Molecular epidemiology of hepatitis C in Australia

The aim of this study was to determine the distribution of hepatitis C virus (HCV) genotypes in Australian patients with hepatitis C and to identify factors associated with particular genotypes. Serum isolates of HCV-RNA were genotyped using a commercial oligonucleotide hybridization (line probe) assay. Relationships between demographic factors, mode of HCV transmission and HCV genotype were assessed by logistic regression analysis. Among 463 patients with hepatitis C, 425 tested positive for HCV-RNA and a single HCV genotype was identified in 420 cases. The patients' places of birth were Australia or New Zealand (62%), Asia (13%), Europe (12%), Mediterranean (6%), Middle East (6%) and other countries (< 1%). The most common genotypes were type 1 (52%) or type 3 (32%); type 2 (9.3%), type 4 (5.5%) and type 6 (1.7%) were less common. Patients with genotype 1b were older (48 +/- 13 years, P< 0.001) and patients with genotype 3 were younger than the remaining patients (37 +/- 11 years vs 42 +/- 12 years, P< 0.001). Among type 1 isolates, 1b was more common for patients born outside Australia compared with those born in Australia (50% vs 13%, P< 0.001) whereas non-1b subtypes were more common among Australian-born patients. Likewise, 21 of 23 (91%) patients with type 4 were from Egypt and six of seven (86%) with type 6 were from Vietnam. The relative importance of parenteral risk factors for HCV also varied according to geographic origin. Thus, a definite risk factor for HCV acquisition was identified in > 95% of Australian-born patients, but in only 33% of Asian or Mediterranean-born patients. Logistic regression analysis indicated that region of birth and risk factor (intravenous drug use or not) would allow 98% of type 4 cases and 76% of type 1b cases to be identified correctly. In summary, region of birth, patterns of migration over time and risk factors for transmission of HCV interact to determine the distribution of HCV genotypes in a multi-racial community like Australia.

A clinical and virological study of hepatitis C virus-related cryoglobulinemia in Germany

BACKGROUND/AIMS

Several reports, especially from Southern Europe, have demonstrated a close association between hepatitis C virus (HCV) infection and mixed cryoglobulinemia. In this study we have analyzed the significance of HCV-related cryoglobulinemia in Germany.

METHODS

Sera from 79 patients with cryoglobulinemia of type I (n=21), II (n=28) or III (n=30) were investigated for HCV markers. Furthermore, 132 consecutive patients with chronic hepatitis C were studied for the presence of cryoglobulins. Genotypes of HCV were determined according to Simmonds, and HCV-RNA concentrations were measured in patients with and without cryoglobulinemia.

RESULTS

In 79 patients with cryoglobulinemia we found anti-HCV antibodies in 17 (22%) and HCV-RNA in 11 patients (14%). HCV antibodies were more frequent in essential (44%) compared to secondary mixed cryoglobulinemia (15%). In 132 patients with chronic HCV infection cryoglobulins were detected in 37 patients (28%), in 21 of them at low levels. Clinical symptoms due to cryoglobulinemia were observed in eight of the 37 patients, severe vasculitis in three patients with high cryocrit-levels and cryoprecipitation at room temperature. HCV genotype 1 and subtype 1b were most prevalent, both in patients with and without cryoglobulinemia, and mean HCV-RNA levels were not different between the two groups. Comparison of HCV-RNA levels in cryoprecipitates, supernatant and native serum suggests binding of HCV-RNA to the cryoprecipitate with different affinity in individual patients.

CONCLUSIONS

The lower prevalence of HCV-related cryoglobulinemia in our study compared with data from Italy and France suggests a south-north gradient in the prevalence of HCV-associated cryoglobulinemia in Europe.

The natural course of chronic hepatitis C: implications for clinical practice

Hepatitis C is an important public health problem with high rates of chronic infection ensuing after viral acquisition. The spectrum of the disease ranges from mild to severe chronic hepatitis, cirrhosis and hepatocellular carcinoma. Extra-hepatic manifestations may occur. The disease is complex and predictions about long-term prognosis for individual patients remain difficult. It is generally accepted that 10-20% of patients with chronic hepatitis C will develop cirrhosis within 10 years of first infection: identifying the group of patients at greatest risk remains a primary challenge for clinicians. Older age of infection, duration of infection, degree of liver inflammation at first biopsy and cofactors such as alcohol abuse, all appear to be predictors of a poorer prognosis. The following paper aims to identify some of the features of the natural history of hepatitis C most relevant to the clinician.

Molecular heterogeneity and new subtypes of HCV genotype 4

The subtype distribution of HCV genotype 4 was studied in two different African countries, Egypt and Tanzania. The HCV isolates were obtained from epidemiological studies involving, respectively, 135 hepatopatic patients and 1043 pregnant women and outpatients. Sequence comparison and phylogenetic analysis of the NS5b genome region (nt 8327-8499) were performed. Fourteen out of 18 isolates from Egypt, but only 3 out of 6 isolates from Tanzania clustered in the same branch of subtype 4a. Three new proposed subtypes have been identified. The first includes 1 isolate from Egypt (EGY15); the second, 2 isolates from Egypt (EGY193 and EGY44) and 2 isolates from Tanzania (D776, D61); and the third, 1 isolate from Egypt (EGY47) and 1 isolate from Tanzania (D70). These isolates cluster in branches different from any other, corresponding to a known subtype of genotype 4. In conclusion, remarkable genetic heterogeneity has been found among genotype 4 isolates simultaneously circulating in a restricted area. This was particularly observed in the study performed in Tanzania. Potential concern about the sensitivity of diagnostic assays and possible implications in the development of future vaccines have been stressed.

Therapy for chronic hepatitis B and C infection in haemophilia

Haemophiliacs, until recently, have been at risk of hepatitis B and C infection. Substantial numbers of patients remain persistently infected. Several lines of evidence suggest that these diseases will cause considerable morbidity unless therapy can successfully reduce viraemia and prevent disease progression. Cessation of viral replication may prevent progression to hepatic fibrosis.

Antipyrine clearance in chronic and neoplastic liver diseases: a study of 518 patients

Antipyrine metabolism is widely used as an index of the drug-metabolizing reserve of the liver. It is well known that metabolism of this drug is impaired in subjects with acute hepatitis or cirrhosis, but conflicting data have been reported regarding patients with chronic postinfectious hepatitis or liver cancer. We studied conventional liver-function parameters and antipyrine metabolism (antipyrine per o.s. 18 mg/kg) in 518 subjects. One hundred and one patients had liver metastases (various primaries). Based on the number and size of lesions, the hepatic involvement was considered minimal in 47 and massive in 54 (groups B1 and B2, respectively). One hundred and two had chronic active hepatitis (CAH); 51 patients with histological evidence of fibrosis/early cirrhosis and 51 patients were without histological evidence of fibrosis/early cirrhosis. Ninety-two had histologically confirmed cirrhosis (group D), and the remaining 120 had cirrhosis and hepatocellular carcinoma (group E). The control group was composed of 103 subjects with healthy livers (group A). Antipyrine clearance (AP Cl) in CAH patients with fibrosis (0.246 +/- 0.98 mL/min per kg) was similar to that observed in patients with cirrhosis (0.223 +/- 0.148 mL/min per kg), and both values were significantly lower than that found in CAH patients without fibrosis (0.406 +/- 0.159 mL/min per kg, P < 0.01). Antipyrine clearance in patients with liver metastases (0.426 +/- 0.174 mL/min per kg) was similar to that of the healthy group (0.489 +/- 0.210 mL/min per kg). Cirrhotics and cirrhotics with hepatocellular carcinoma (HCC) presented similar degrees of impairment. Antipyrine clearance was positively correlated with serum albumin (r2 = 0.10, P = 0.01) and prothrombin time (r2 = 0.129, P < 0.01) in all groups, except those with liver metastases. In patients with CAH, the presence of fibrosis/cirrhosis is associated with impaired antipyrine metabolism. The lack of impairment in groups with liver metastases suggests that the functional hepatic reserve is maintained even in the presence of massive neoplastic invasion.

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.

How much does alcohol contribute to the variability of hepatic fibrosis in chronic hepatitis C?

In order to determine the contribution of alcohol intake to the severity of hepatic fibrosis in patients with chronic hepatitis C, we studied associations between various levels of alcohol intake, other demographic variables and semiquantitative liver histology in 434 cases of chronic hepatitis C. Clinical, demographic and disease-related data were entered into a relational database. Liver histology was scored according to Scheuer. The average daily alcohol intake for the year preceding liver biopsy (recent exposure) and for earlier periods (past exposure) was categorized into five levels of intake. One-third of patients gave a history of alcohol intake that had exceeded 40 g/day for at least 5 years. By univariate analysis, age, but not recent or past alcohol intake or other baseline variables, was associated with portal score (r = 0.14, P = 0.004), fibrosis score (r = 0.46, P < 0.001), total Scheuer score (r = 0.35, P < 0.001). However, by multivariate analysis, age (P < 0.001), past (but not present) alcohol intake (P < 0.001) and birth in Egypt (P = 0.006) were independently associated with fibrosis score. Age, past alcohol and birth place in Egypt contributed 27% to total variance of the hepatic fibrosis score, while age alone accounted for 23%. Age also independently predicted portal activity (P = 0.02) and total Scheuer score (P < 0.001), whereas past alcohol intake correlated with total Scheuer score (P = 0.002) but not with other histological indices. A separate multivariate analysis was performed on a more homogeneous subgroup of 196 patients who acquired hepatitis C by injection drug use. In this subgroup, age (P < 0.05) and past alcohol (P < 0.05) were independently associated with fibrosis score. In both the overall and subgroup analyses, there was a threshold level of past alcohol intake (>80 g/day) beyond which the risk of fibrosis increased significantly. It is concluded that toxic levels of alcohol exposure for at least 5 years accentuate hepatic fibrosis in hepatitis C but the influence of alcohol appears to be minor compared with age and other variables and is exerted only at toxic levels of intake.

Epidemiology of hepatitis C and G in sporadic and familial porphyria cutanea tarda

From 1995 to 1997, we prospectively evaluated the prevalence of hepatitis C virus (HCV) RNA in 124 patients with porphyria cutanea tarda (PCT) from Northern France (83 sporadic and 41 familial PCT). Serum samples were analyzed for ferritin, transaminases, HCV antibodies, and HCV RNA. In addition, genotyping of HCV and searches for HCV infection risk factors (blood transfusion, iv drug abuse, and surgical intervention) were performed. Twenty-six of 124 patients (21%; 95% CI: 13.9-28) were positive for serum HCV antibodies. All of them were also positive for HCV RNA. The prevalence of HCV infection was higher in the sporadic PCT group (26.5%, 22 out of 83) than in the familial PCT group (9.7%, 4 out of 41). Risk factors for hepatitis C infection were found to be significantly increased in the HCV-positive group when compared with the HCV-negative PCT group. In all HCV-positive patients with a risk factor, the suspected date of exposure to the virus always preceded the clinical onset of PCT. The HCV genotype pattern in PCT patients was similar to that observed in nonporphyric HCV patients in western European countries. Serum ferritin level was increased in both HCV-positive and HCV-negative porphyric patients. Transaminase levels were significantly higher in HCV-infected PCT patients. Sixty-seven out of 124 patients were retrospectively studied for hepatitis G virus (HGV) infection. Six of these 67 patients (8.9%; 95% CI: 2.1-15.8) were positive for HGV RNA. None of the six HGV-infected patients were positive for HCV RNA. The HGV-infected patients did not differ statistically from those without HGV infection with regard to age, ferritin, transaminase levels, and PCT treatment. These results support the view that sporadic cases of HGV infection may occur frequently. This study of a large cohort of HCV and PCT patients further documents an increasing gradient in HCV prevalence from northern to southern Europe, and shows that HCV infection acts as a triggering factor of PCT. Finally, the HGV prevalence found in the PCT patients was comparable with that found in French blood donors, suggesting that HGV is not a PCT triggering factor.

Hepatitis C virus (HCV) genotypes in Spanish patients with HCV infection: relationship between HCV genotype 1b, cirrhosis and hepatocellular carcinoma

BACKGROUND/AIMS

The influence of the infecting virus genotype on the progression of the underlying liver disease in patients with chronic hepatitis C virus (HCV) infection remains controversial. The aim of this study was to investigate the prevalence of HCV genotypes in Spanish patients with chronic HCV infection and to elucidate the relationship between the infecting genotype and the severity of the disease.

METHODS

A cross-sectional, retrospective analysis of frequency distribution of HCV genotypes was carried out in 414 Spanish patients with chronic HCV infection, including 243 patients with asymptomatic or minimally symptomatic chronic hepatitis, 112 patients with cirrhosis and hepatocellular carcinoma and 59 patients with decompensated cirrhosis. HCV genotype was determined by restriction fragment length polymorphisms of the 5' non-coding region.

RESULTS

Infection with HCV genotype 1b was found in 72% of patients with chronic hepatitis and in more than 90% of patients with cirrhosis, with or without hepatocellular carcinoma. Older age, infection with genotype 1b and absence of overt parenteral exposure as a possible source of infection were associated with cirrhosis and hepatocellular carcinoma by univariate analysis and this association was confirmed by regression analysis.

CONCLUSIONS

HCV genotype 1b is associated with advanced liver disease in our geographical area. However, this may be related to a cohort-effect caused by over-representation of genotype 1b in older patients with more advanced disease, because, in our country, this HCV genotype appeared earlier in time and is therefore associated with more prolonged periods of infection.

Review: molecular epidemiology of hepatitis C virus

Molecular techniques have been used to investigate the epidemiology of hepatitis C virus (HCV) at several different levels. At a global level, the time of divergence of the diverse HCV genotypes isolated from different geographical regions has been estimated from the rate of divergence observed among a cohort of individuals infected from a common source. Estimates of more than 300 years for virus subtypes and more than 500-2000 years for virus types are consistent with their current geographical distributions. Analysis of virus sequences has also provided evidence for a common source of infection in several large-scale outbreaks of HCV infection, although where there is evidence that the implicated source contains more than one variant it may be difficult to distinguish individuals infected by different sources. Finally, sequence analysis has been used to investigate the vertical or horizontal transmission of HCV between pairs of individuals. The hypervariable region of the E2 gene is the most informative region to study if samples are available soon after the transmission event, but evidence for more distant events can still be obtained from analysis of genes such as NS5b and E1. Interpretation of some studies is complicated by the conservation of the gene region studied, or by the failure to make comparisons with sequences from epidemiologically unrelated viruses.

Viral hepatitis in older adults

The objective of this paper is to review the epidemiology, manifestations, therapy, and prevention of viral hepatitis in older people and to discuss issues of prevention and management. In developed countries a significant portion of the adult population is not immune to Hepatitis A virus (HAV). Morbidity and mortality from HAV infection increases with age. A safe and effective hepatitis A vaccine is available and health authorities should consider immunization early in life and for healthy adults as well as for potential high risk groups such as nursing home residents. Acute hepatitis due to Hepatitis B virus (HBV) is rare in older people and is usually a mild disease. Most older patients with chronic HBV infection who suffer from advanced liver disease have no evidence of ongoing viral replication. Therefore, they are not candidates for interferon therapy. Those with evidence of ongoing viral replication and compensated liver disease should be offered interferon or be included in clinical trials with new antiviral drugs such as lamivudine. Since the response rate to hepatitis B vaccination decreases with age, developing vaccines with greater immunogenicity is crucial. Hepatitis C virus (HCV) is the most frequent cause of acute viral hepatitis in older people. Acute hepatitis C is usually a mild disease in this age group. Because many older patients with chronic HCV infection have compensated liver disease, they could benefit from antiviral therapy. In light of the low response rate to interferon in older patients with chronic hepatitis C and the side effects of the drug, interferon therapy should be reserved for those with the best chance of response. "Combination" antiviral therapy should be on trial for older patients with chronic HCV infection who do not respond to interferon. The recently discovered RNA virus, Hepatitis G (HGV), has been associated with liver disease in older people. It's role in the pathogenesis of liver injury remains to be elucidated.

[Therapy of hepatitis C]

The purpose of this review is an update of the therapy of hepatitis C especially with Interferon-alpha. From the large number of publications on this topic the established facts were worked out. Taking these facts as a base guidelines for the therapy in practical use were defined. In addition the aspects of therapeutic strategies of chronic hepatitis C which until now can not definitely be judged are discussed. In the relatively few patients in whom hepatitis C is diagnosed already in the acute phase, Interferon-alpha-treatment (3 x 3 million units 3 times a week) for 3 to 4 months increases the percentage of patients in whom HCV-RNA in the serum is eliminated. In patients with chronic hepatitis C, after decision finding for treatment, a standard scheme is recommended which consists of a monotherapy with recombinant Interferon-alpha. The dosage of Interferon-alpha is in the first 12 to 16 weeks 5 up to 6 million units given 3 times a week. For the further therapy 3 million units 3 times a week seems to be appropriate. The recommended duration of Interferon-alpha-therapy is 12 months. A long-term benefit of about 20% can be achieved in unselected groups of patients when judged on the permanent normalisation of serum transaminases and elimination of HCV-RNA in the serum. Important factors which may influence the probability of a sustained response, like HCV genotype, virus titer in serum, duration of the disease, high hepatic iron content and the presence of cirrhosis, are discussed. Up to now there exist no reliable guidelines in the case of a "no change" situation and for patients with a flare-up of inflammatory activity during or after therapy. Combination therapy of Interferon-alpha with other drugs like analogous of nucleotides (for example ribavarin), non steroidal antirheumatic drugs and ursodesoxycholic acid (UDCA) have still to be evaluated in controlled clinical trials.