Pretreatment viral load and response to prolonged interferon-alpha course for chronic hepatitis C

Adipocytokine involvement in hepatocellular carcinoma after sustained response to interferon for chronic hepatitis C

AIM

  Interferon (IFN) dramatically reduces the risk of hepatocellular carcinoma (HCC) after a sustained virological response (SVR) to chronic hepatitis C (CH-C). However, HCC still develops in some patients after SVR. To evaluate metabolic factors in patients with HCC occurring after SVR and to determine whether insulin resistance and adipocytokines were involved in this etiology.

METHODS

  We examined clinical and biochemical features, histological findings and serum levels of adipocytokine prior to IFN therapy and at the detection of HCC in nine patients who were diagnosed with HCC. As controls, 27 patients were included who showed SVR but had not been diagnosed with HCC for at least 5 years after SVR.

RESULTS

  Three of four patients who developed HCC within 5 years after SVR showed liver cirrhosis when HCC was diagnosed. Prior to IFN therapy, four of nine HCC patients were diagnosed as having type 2 diabetes mellitus. Serum levels of leptin and insulin, Homeostatic Model of Assessment of Insulin Resistance and body mass index (BMI) were significantly higher and serum adiponectin was significantly lower in HCC patients at the time of HCC detection than in control patients more than 5 years after SVR. Six HCC patients had increased BMI and one HCC patient had a decreased BMI during the observation period.

CONCLUSION

  Hepatic fibrosis may be tightly related to the emergence of HCC after SVR. Insulin resistance and adipocytokine disorders may be implicated in hepatocarcinogenesis after SVR, in part by promoting hepatic fibrosis.

Efficacy of low dose long-term interferon monotherapy in aged patients with chronic hepatitis C genotype 1 and its relation to alpha-fetoprotein: A pilot study

AIM

The objective of this study was to examine the efficacy and safety of low dose long-term interferon (IFN) therapy in aged patients with chronic hepatitis C genotype 1.

METHODS

The IFN therapy was performed in Shin-Kokura Hospital on 44 patients aged 60 or older with chronic hepatitis C. All patients had high viral loads of genotype 1. Three million units of natural IFN-alpha was administered intramuscularly or intrasubcutaneously, three times a week for three years. A control group of 44 subjects not treated with IFN, matched for age, gender and hepatic histology, was formed.

RESULTS

Two of the 44 patients showed a sustained virological response. Alanine aminotransferase was below the upper limit of normal in 59% (23/39) of the patients and alpha-fetoprotein was less than 40 ng/mL in 97% (38/39) on the completion of treatment. Sustained biochemical response was observed in 53% (19/36) of the patients. In the liver cirrhosis group, serum albumin values and platelet counts increased in 38% (6/16) and 33% (6/18) of patients, respectively. Hepatocellular carcinoma (HCC) appeared in three patients by 13 months after the start of treatment, but no cases were reported thereafter. The cumulative non-carcinogenesis rate of HCC in the liver cirrhosis group was significantly higher in the IFN treatment group compared to the control group (log-rank test, P = 0.046).

CONCLUSION

Low dose long-term interferon monotherapy to prevent carcinogenesis of HCC was considered useful in aged patients for whom peg-interferon and ribavirin combination therapy is difficult.

The role of genomic and antigenomic HCV-RNA strands as predictive factors of response to pegylated interferon plus ribavirin therapy

BACKGROUND

Hepatitis C virus replicates by the synthesis of an antigenomic HCV-RNA. As the end point of anti-viral therapy is to decrease viral replication, the amount of antigenomic HCV-RNA could influence the response.

AIM

To study if amounts of genomic and antigenomic HCV-RNA in the baseline liver biopsy are predictive factors of response to anti-viral therapy.

METHODS

Eighty-eight patients with chronic HCV infection (anti-HIV-negative) treated with pegyltaed-interferon-alpha2b plus ribavirin for 12 months were included. Intrahepatic genomic and antigenomic HCV-RNA concentrations were determined by real-time polymerase chain reaction and percentage of infected hepatocytes by in situ hybridization.

RESULTS

Of the 88 patients, 31% were responders while 69% were not. Median of antigenomic HCV-RNA in liver of responders and non-responders was 120 000 copies/microg RNA (range: 10,000-775,000) vs. 150,000 copies/microg RNA (range: 100-3,200,000; P = 0.38). Median of genomic HCV-RNA in liver of responders was 1,250,000 copies/microg RNA (range: 5000-9,000,000) and in non-responders 3,180,000 copies/microg RNA (range: 4600-18,000,000; P = 0.0191). Predictive factors of response in the logistic regression were: intrahepatic amount of genomic HCV-RNA, percentage of infected hepatocytes and previous therapy.

CONCLUSION

Response to 12 months of therapy with pegylated interferon-alpha2b plus ribavirin depends on the amount of genomic HCV-RNA in the pre-treatment liver biopsy.

Replicative homeostasis III: implications for antiviral therapy and mechanisms of response and non-response

While improved drug regimens have greatly enhanced outcomes for patients with chronic viral infection, antiviral therapy is still not ideal due to drug toxicities, treatment costs, primary drug failure and emergent resistance. New antiviral agents, alternative treatment strategies and a better understanding of viral pathobiology, host responses and drug action are desperately needed. Interferon (IFN) and ribavirin, are effective drugs used to treat hepatitis C (HCV), but the mechanism(s) of their action are uncertain. Error catastrophe (EC), or precipitous loss of replicative fitness caused by genomic mutation, is postulated to mediate ribavirin action, but is a deeply flawed hypothesis lacking empirical confirmation. Paradoxically ribavirin, a proven RNA mutagen, has no impact on HCV viraemia long term, suggesting real viruses, replicating in-vitro, as opposed to mathematical models, replicating in-silico, are likely to resist EC by highly selective replication of fit (~consensus sequence) genomes mediated, in part, by replicative homeostasis (RH), an epicyclic mechanism that dynamically links RNApol fidelity and processivity and other viral protein functions. Replicative homeostasis provides a rational explanation for the various responses seen during treatment of HCV, including genotype-specific and viral load-dependent differential response rates, as well as otherwise unexplained phenomena like the transient inhibition and rebound of HCV viraemia seen during ribavirin monotherapy. Replicative homeostasis also suggests a primarily non-immunological mechanism that mediates increased immune responsiveness during treatment with ribavirin (and other nucleos(t)ide analogues), explicating the enhanced second-phase clearance of HCV ribavirin promotes and, thus, the apparent immunomodulatory action of ribavirin. More importantly, RH suggests specific new antiviral therapeutic strategies.

Percentage of hepatitis C virus-infected hepatocytes is a better predictor of response than serum viremia levels

Pegylated alpha-interferon plus ribavirin is the current therapy for chronic hepatitis C virus (HCV) infection. Serum HCV-RNA concentration before treatment has been identified as an independent predictive factor of response. We have compared the percentage of HCV-infected hepatocytes with the concentration of serum HCV-RNA in baseline samples as predictors of response. We included 97 patients with chronic HCV infection (genotype 1), treated with pegylated-interferon-alpha2b plus ribavirin. Of these 97, 38 (39%) were sustained responders and 59 (61%) were not. Statistical differences between responders and nonresponders were found regarding the percentage of infected hepatocytes (6.83+/-4.50% versus 13.44+/-10.05%; P=0.00003) but not in serum HCV-RNA concentration [1.71+/-2.70 (x10(6) IU/L) versus 1.32+/-1.86 (x10(6) IU/L); P=0.40694]. Other factors associated with response were age, gamma-glutamyl transpeptidase level, and absence of previous therapy. Logistic regression demonstrated that percentage of infected hepatocytes (odds ratio, 1.160; 95% confidence interval, 1.065-1.264) and previous therapy (odds ratio, 0.294; 95% confidence interval, 0.109-0.795) were significant predictive factors for response. Therefore, the percentage of infected hepatocytes in liver biopsy before treatment is a better predictive factor of sustained response to 48 weeks of therapy with pegylated alpha-interferon plus ribavirin than serum HCV-RNA concentration in baseline serum sample.

A decade of trials of interferon-alpha for chronic hepatitis C. A meta-regression analysis

The most relevant randomized controlled trials of interferon-alpha (IFN) for naive patients with chronic hepatitis C (CHC) published in a decade, just before appearance of pegylated IFN trials in 2000, were included in this paper. Its purpose is to review the relationship between sustained biochemical response in active versus control group versus usual clinical variables as IFN regimens, cirrhosis, genotype and versus less frequently addressed variables as funding, methodological quality or location of principal author. Meta-analysis estimates of global treatment effect varied according to trial design: group 1=IFN versus placebo/no treatment, 32 RCTs, 2499 pts, OR 9.5 (6.3-14.2); group 2a=comparison of IFN schedules, 43 RCTs, 7454 pts, OR 1.6 (1.4-1.9); group 2b=IFN+other drugs versus standard IFN, 30 RCTs, 4737 pts, OR 2.0 (1.6-2.6). Fixed effects (arm-level) meta-regression on the complete data set (171 arms, 10,580 pts) revealed that sustained response was most likely in experimental arms of IFN+ribavirin or other drugs (OR 2.4), arms using yearly schedule (OR 2.0), trial principal author from Asia (OR 1.7), trial sample size >200 (OR 1.4) and arms enrolling less than 50% of cirrhotics (OR 1.3). Moreover, focus was on some significant interactions too, as the effect of trial's quality interacting to the recorded funding (more benefit if no-profit, less if for-profit) and the effect of trial funding interacting to the location of first author (more benefit if from Asia). Three main effects (experimental arm, cirrhosis, funding) and one interaction (funding*location of principal author) explained 31% of between study variability in a random-effect meta-regression. In a subgroup analysis on a data set including available information on HCV genotype (93 arms, around 7000 pts), meta-regression revealed that genotype 1 or 4 less than 50% per arm and specialistic journal were significant predictors of either biochemical (transaminases) or virological (HCV-RNA) sustained response, in a model including the same main effects identified in the complete data set analysis. Finally, although mostly captured by different IFN regimens along time, heterogeneity of effect in a large set of (not-pegylated) IFN trials was also explained by HCV genotype and variables of quality and reporting, such as trial's principal author from Asia.

Treatment with interferon-alpha2b of naive non-cirrhotic patients with chronic hepatitis C according to viraemia and genotype. Results of a randomized multicentre study. The North West Italian Hepatological Group

OBJECTIVE

To establish whether tailoring the dosage of interferon (IFN)-alpha2b in non-cirrhotic naive patients with chronic hepatitis C according to hepatitis C virus (HCV) genotype and viraemic level improves the rate of sustained response (normal alanine aminotransferase values and HCV-RNA negativity 6 months after the end of therapy).

PATIENTS

A total of 538 consecutively collected HCV-positive patients with non-cirrhotic chronic hepatitis who had not been previously treated.

METHODS

Quantitative viraemia and genotype were determined in each patient by a core laboratory. The patients were randomized to: Group 1, 86 patients with genotype non-1 and viraemia < 1,000,000 HCV genome equivalents/ml (GenEq/ml) treated with 3 Million Units (MU) IFN three times weekly (t.i.w.) for 1 year; Group 2, 42 patients with genotype 1 and viraemia < 1,000,000 GenEq/ ml treated with 3 MU IFN t.i.w. for 1 year; Group 3, 46 patients with genotype 1 and viraemia < 1,000,000 GenEq/ ml treated with 5 MU IFN t.i.w. for 1 year; Group 4, 85 patients with genotype non-1 and viraemia > 1,000,000 GenEq/ml treated with 3 MU IFN t.i.w. for 1 year; Group 5, 88 patients with genotype non-1 and viraemia > 1,000,000 GenEq/ml treated with 5 MU IFN t.i.w. for 1 year; Group 6, 94 patients with genotype 1 and viraemia > 1,000,000 GenEq/ml treated with 3 MU IFN t.i.w. for 1 year; Group 7, 97 patients with genotype 1 and viraemia > 1,000,000 GenEq/ml treated with 5 MU IFN daily for 2 months followed by 5 MU t.i.w. for a further 10 months.

RESULTS

According to an intention-to-treat analysis, a sustained virological response (negative HCV-RNA by polymerase chain reaction 6 months after the end of therapy) was observed in 42% of Group 1 patients, in 21% of Group 2 patients versus 24% of Group 3 patients [P = not significant (NS)], in 28% of Group 4 patients versus 35% of Group 5 patients (P = NS), and in 8.5% of Group 6 patients versus 12% of Group 7 patients (P = NS).

CONCLUSIONS

Even though a trend towards a therapeutic improvement is observed, the adoption of more aggressive IFN protocols, such as induction therapy, does not appear to significantly improve the rate of sustained response in patients with chronic hepatitis C associated with HCV genotype 1 and highly viraemic levels compared with standard therapy. Moreover, patients with only one unfavourable predictive factor (genotype 1 or high viraemia) do not gain major therapeutic benefits when treated with high doses of IFN.

Retreatment with interferon for chronic hepatitis C after transient response

Approximately half of all patients with chronic hepatitis C show an initial biochemical response to interferon, but only 15% to 20% of patients achieve a sustained response. We studied the efficacy of retreatment with interferon for patients with chronic hepatitis C who showed transient biochemical responses to initial treatment. Thirty patients who relapsed were retreated 1 to 52 months (median 14) after the end of initial treatment, according to the previously used regimens. The responses were correlated with the pre-retreatment patient data. The liver histologic grades, compared with those found before the initial treatment, were better in eight (27%) patients but worse in six (20%), whereas the fibrosis stage was improved in five (17%) but worsened in eight (27%). All patients displayed end-of-retreatment biochemical responses. Of the 30 patients, 10 (33%) achieved sustained aminotransferase normalization and serum hepatitis C virus (HCV) RNA clearance, but the remaining 20 patients showed relapse within 1 year after cessation of retreatment. Univariate analysis associated the sustained response with low pre-retreatment viral loads (0.8 +/- 0.7 MEq/mL vs. 9.1 +/- 6.5 MEq/mL; p = 0.006), short treatment intervals (13 +/- 13 months vs. 22 +/- 14 months; p = 0.031), and low histologic grades (1.3 +/- 0.7 vs. 1.9 +/- 0.7; p = 0.039). However, multivariate analysis indicated that only the pre-retreatment viral load was predictive of the sustained response (p = 0.049). These findings suggest that transient responders to interferon are likely to respond to retreatment but the achievement of a sustained response depends on the HCV viral load before retreatment.

Quantitation of HCV RNA in liver of patients with chronic hepatitis C

BACKGROUND/AIMS

Liver HCV RNA has been quantitated in few studies and the feasibility and the role of this parameter in the evaluation of patients with chronic HCV hepatitis still warrant study. Our aim was to determine the concentrations of HCV RNA in the liver of chronic HCV patients and to correlate the results with serum viral load. We also studied the relation of levels of HCV RNA in the liver with serum aminotransferases levels and with the presence of cirrhosis.

METHODS

Twenty patients (14 males, aged 28 to 61 years) were studied. Twelve were infected by HCV type 1, six by type 3 and one by type 5. Percutaneous liver biopsy samples were obtained from 14 patients, and the remainder from liver explant in patients undergoing OLT. Twelve had chronic hepatitis and eight cirrhosis. HCV RNA levels were determined by bDNA.

RESULTS

HCV RNA levels below the detection limit were found in one liver and in five serum samples. HCV RNA (mean +/- SD) was 2.1 x 10(8) +/- 2.2 x 10(8) Eq/gm in the liver and 94 x 10(5) +/- 93 x 10(5) Eq/mL in serum, with a significant correlation between these values (r = 0.89; P < 0.0001). Serum HCV RNA levels were significantly lower (P = 0.001) in cirrhotic than in chronic hepatitis patients, while the groups did not differ in liver HCV RNA levels. No correlation was observed between liver or serum HCV RNA and serum ALT or AST.

CONCLUSIONS

Quantitation of HCV RNA is possible even in small liver samples. Although average levels are more than one log higher than those observed in serum, hepatic concentrations correlate with those observed in serum. The application of this technology to monitoring antiviral therapy and understanding the pathogenesis of the disease remains to be determined.

Clinical characteristics of patients with chronic hepatitis C showing biochemical remission, without hepatitis C virus eradication, as a result of interferon therapy. The Osaka Liver Disease Study Group

During long-term follow-up of patients chronically infected with the hepatitis C virus (HCV) and treated with interferon (IFN), we identified some who had persistent normalization of serum alanine aminotransferase (ALT) but remained positive for HCV RNA. The aims of this study were to clarify the characteristics of these patients and to examine their clinical outcome after treatment. Nine hundred and ninety-eight patients treated with IFN were followed-up biochemically and virologically, and by liver ultrasound, for 13-95 months. A short-term biochemical sustained response, where ALT remained within the normal range for 6 months after the completion of IFN therapy, was found in 296 patients; in 240 of these patients serum HCV RNA remained undetectable during long-term follow-up. The rate of HCV RNA persistence was 7.09 times greater in short-term biochemical sustained responders with a high viral load than in those with a low viral load (P=0.0001, odds ratio [OR]=7.09), and 3. 70-fold lower in those treated with a large dose of IFN than in those treated with a small dose (P=0.02, OR=0.27). Thirty-three (59%) of 56 patients without HCV eradication showed continuous ALT normalization for 26-80 months after cessation of IFN therapy. Short-term biochemical sustained responders who were older (P=0.009, OR=10.43) and who were male (P=0.03, OR=6.98) had a significantly greater probability of maintaining a normal ALT level, even when serum HCV RNA was positive. When the incidence of HCC was investigated during long-term follow-up in patients without HCV eradication, it was found to be significantly lower in patients with persistently normal ALT levels than in those with abnormal ALT levels (P=0.03). Hence, when HCV is not eradicated as a result of IFN therapy, it may induce a long-term carrier state of HCV infection with normal ALT levels in older or male patients, in whom the cumulative incidence of HCC is markedly decreased.

Case selection for interferon treatment of hepatitis C

To establish a case selection algorithm for the treatment of hepatitis C, predictive factors were studied and reported articles were reviewed and analysed. Because of the relatively poor efficacy of interferon (IFN) monotherapy, which is ineffective in 60-70% of patients, case selection at present is determined by the likelihood of attaining a sustained response (SR; defined by normalizing serum ALT and eliminating serum HCV RNA after treatment) to therapy. According to the present study, viral load and genotype, and IL-10 and IL-1ra serum levels, are the most predictive of achieving SR after IFN monotherapy given in a comparatively high dose regimen for 6 months. In addition, reported studies with logistic analyses were carefully reviewed and analysed for the most effective predictive factors of case selection. The results again indicated that viral load and HCV-genotype (serotype). were closely related to SR. Age, gender, and histological changes at treatment were also considered for case selection. These results, however, relate solely to IFN-monotherapy. Future development of more effective strategies for treating hepatitis C could alter the exclusion criteria for IFN treatment and will negate the need for the case selection algorithm discussed here.

Methodological issues in papers on IFN therapy: time for reappraisal

We conducted an analytical review of 194 full papers on interferon (IFN) therapy for chronic hepatitis C to evaluate current methodology (i.e. study design, criteria for evaluating the efficacy of therapy and predictors of response). Of the papers evaluated, 64 were randomized controlled trials (RCT), 40 were non-randomized controlled trials (NRCT) and 90 were observational studies (OS). The methodological analysis was focused mainly on clinical trials. The number of patients enrolled in RCT was higher compared with the number enrolled in NRCT. Uniform enrolment criteria were used in less than 50% of the trials. Only 20% of RCT and 2.5% of NRCT used criteria for defining sample size. The response rate was calculated on an intention-to-treat basis in 36 of the RCT and in 14 of the NRCT. The outcome of treatment and the criteria employed to define the response to treatment were found to be far from standardized. In 51.5% of the RCT and 42.5% of the NRCT, normalization of alanine aminotransferase (ALT) level at the end of follow-up was the only marker of response studied. Only 57.6% of the trials considered histological evidence as an important outcome. Among the clinical trials, 71.1% evaluated predictors of good response to IFN therapy. In 51% of the OS, ALT normalization by the end of follow-up was the only criterion for defining response. In conclusion, to ensure a high level of reliability in comparing or combining the results of different studies, some basic general requirements must be followed when planning trials on antiviral therapy.

Hepatitis C virus genotypes in a non-cirrhotic Italian population with chronic hepatitis C: correlation with clinical, virological and histological parameters. Results of a prospective multicentre study

To identify correlations between the distribution of hepatitis C virus (HCV) genotypes and demographic, pathological and virological parameters of HCV-infected patients, we prospectively recruited 650 patients with biopsy-proven chronic hepatitis C without histological aspects of cirrhosis; none had been treated with antiviral therapy. Data regarding gender, age, mode of HCV transmission, alanine aminotransferase (ALT) and HCV RNA levels, immunoglobulin M (IgM) anticore values, liver histology and histological activity were obtained from each patient and correlated on multivariate analysis with infecting HCV genotype. Fifty-five per cent of the patients were infected with HCV genotype 1, 20% with HCV genotype 2, 18% with HCV genotype 3 and 7% with HCV genotype 4. Non-transfusional HCV transmission, low ALT levels, IgM anticore reactivity and a low histological grading score were independent variables associated with HCV genotype 1. Older age, female gender, post-transfusional transmission and a high histological grading score were related to HCV genotype 2, whilst younger age, history of current/previous drug abuse, high ALT values, low IgM anticore reactivity and high viraemic levels were associated with HCV genotype 3. History of illicit use of intravenous drugs and low HCV RNA levels were the only independent variables correlated with HCV genotype 4. Genotype 1 remains predominant in Italy but the prevalence of HCV genotypes is changing in relation to age and mode of transmission: Italian patients with HCV genotype 3 are younger and exhibit higher levels of ALT and HCV RNA than patients with other genotypes.

Biochemical and viral response to consensus interferon (CIFN) therapy in chronic hepatitis C patients: effect of baseline viral concentration. Consensus Interferon Study Group

OBJECTIVE

The effect of baseline viral concentration on response was assessed as part of a multicenter phase 3 trial evaluating the safety and efficacy of CIFN therapy for chronic HCV infection.

METHODS

Patients (n = 472) received either CIFN 9 microg or IFN alpha-2b 3 MU subcutaneously t.i.w. for 24 wk, followed by 24 wk of observation.

RESULTS

Efficacy was assessed by the percentage of patients who achieved normal ALT values or undetectable HCV RNA values (using RT-PCR with a sensitivity of 100 copies/ml). There was a clear relationship between baseline viral concentration and either ALT or HCV RNA response; patients with lower titer HCV RNA had better response rates. End-of-treatment HCV RNA responses were better for patients with low viral concentrations treated with CIFN (51%) than for patients treated with IFN a-2b (31%) (p = 0.03). ALT responses in patients with low viral concentrations were 60% for CIFN-treated patients and 27% for IFN alpha-2b-treated patients (p < 0.01) at the end of treatment. Patients with high titer HCV RNA were more likely to have a sustained HCV RNA response after treatment with CIFN 9 microg, compared with those treated with IFN alpha-2b (7% vs 0%, p = 0.03).

CONCLUSIONS

Both genotype and baseline viral concentration were independent factors that affected response to interferon.

[Characteristics of the hepatitis C virus and viral predictors of therapeutic response]

NATURAL HISTORY OF HEPATITIS C-INFECTION AND VIRAL CHARACTERISTICS: Hepatitis C-virus (HCV) infection is a major cause of non-A, non-B-hepatitis and, additionally, is associated with liver cirrhosis and hepato-cellular carcinoma. The high degree of chronificity of HCV-infection is reasonable due to antigenic variability of neutralizing epitopes leading to incomplete immunoresponse with subsequent virus persistence. Besides genetic variants of HCV within a virus population (quasispecies nature of HCV), different genotypes are classified being genetically and phenotypically distinct, and geographically restricted in part. Genotyping of HCV is not only important for phylogenetic and epidemiological studies, but also a predictive marker for pathogenesis and therapy. VIRAL PREDICTORS OF HCV THERAPY: In a meta-analysis of 18 therapeutical studies of chronical HCV infections, genotype 1 and high levels of viremia determined markedly the response to interferon therapy. In this context, clinical trials have proven the effect of a combined therapy with interferon and ribavirin. Especially patients with HCV genotype 1 or high levels of viremia had a real benefit from combined antiviral therapy in comparison to monotherapy with interferon. CONCLUSION AND FUTURE CONCEPTS: Besides recent concepts improving the therapeutical response to HCV infection, further effort is necessary to develop more successful strategies for eradication of hepatitis C virus. In this context, variations of interferon therapy should be evaluated (e.g. higher and daily doses, longer duration of interferon therapy, "retarded" interferon (PEG-IFN). In addition, new therapeutical concepts should be performed including a combination of interferon with other known antiviral agents (amantadine), a combination with immunomodulators (GM-CSF, thymosin alpha 1), the development of new antiviral agents (inhibitors of viral proteases, helicases and polymerases) and the exploration of anti-viral, molecular strategies (specific ribozymes, antisense oligonucleotides and DNA-vaccination). Nevertheless, the development of an effective vaccination should be the most important challenge for the future.

Clinical use of hepatitis C virus tests for diagnosis and monitoring during therapy

This article reviewed various methods used for the diagnosis and monitoring of HCV infection and discusses potential clinical applications. Substantial improvements have recently been made in assay technology. Moreover, the role of molecular testing in the clinical setting of hepatitis C is becoming better defined. The major challenge facing clinical laboratories is the further refinement, implementation, and standardization of optimized molecular tests, so that reliable data may be made available to clinicians. In turn, clinicians must understand the limitations of each methodology, including the variability of testing that may occur among different laboratories. As more experience is gathered, molecular testing will probably provide important data regarding the most effective use of current and future therapies for individual patients to achieve maximum benefit in the management of hepatitis C.

Chronic hepatitis C and interferon alpha: conventional and cumulative meta-analyses of randomized controlled trials

OBJECTIVE

The purpose of this study was to evaluate the clinical usefulness of surrogate markers of the interferon effect (i.e., alanine aminotransferase levels and serum HCV-RNA status) as predictors of long term response, and to identify the optimal schedule of treatment for patients with chronic hepatitis C by means of meta-analysis.

METHODS

Pertinent randomized clinical trials and prospective studies were selected using MEDLINE (1986-1996), a reference list from published articles or reviews. Twenty-six prospective studies reporting data on surrogate markers of interferon response were selected. Thirty-nine trials comparing interferon alpha to no treatment and 25 trials comparing different schedules of interferon were reviewed. Conventional meta-analysis according to the DerSimonian and Laird method was used for the pooling of results.

RESULTS

The pooled probability of late relapse among sustained responders with negative serum HCV-RNA 6 months after treatment was very low (8.7%; 95% confidence interval 5.8-11.6%). The overall risk difference between treated and control groups was 16.63% (95% confidence interval 11.95-21.31%) for sustained aminotransferase normalization. Therapy with higher interferon dose compared with standard dose significantly improves the rate of sustained response (pooled risk difference 10.56%, 95% CI 5.47-15.65%). Cumulative meta-analyses suggest that a clear dose-response relationship exists across a wide range of interferon dosages. The multivariate meta-regression model confirms that the total interferon dose is an independent predictor of sustained response and that it seems more important than the length of treatment.

CONCLUSIONS

Testing for serum HCV-RNA, 6 months after interferon therapy in sustained biochemical responders, is useful for predicting long term response. The current standard total interferon dose of 234 mega-units is suboptimal. Further trials that directly compare different schedules of treatment are needed.

Reinforced regimen of interferon alfa-2a reduces the incidence of cirrhosis in patients with chronic hepatitis C: a multicentre randomised trial. Multicentre GER-CYT-04 Group

BACKGROUND/AIMS

Our aim was to assess and compare the long-term effect of interferon at standard (6 months) and reinforced dose and duration regimens in chronic hepatitis C.

METHODS

A multicentre institutional trial included 244 previously untreated patients with chronic hepatitis C, without cirrhosis, who were randomly allocated to either standard (3 MU thrice a week for 24 weeks; n=120) or reinforced (6 MU daily for 12 days, 6 MU thrice a week for 22 weeks, 3 MU thrice a week for 24 weeks; n=124) regimens. The main endpoint was sustained ALT response at 72 weeks (18 months); secondary end-points were virological (branched DNA and PCR) and histological responses (incidence of cirrhosis) at month 18.

RESULTS

Sustained ALT response was observed in five patients (4%, 95% confidence interval 0-8%) in the standard group and in 21 patients (18%, 95% confidence interval 11-25%), from the reinforced group (p=0.002), in agreement with virological response in 21 (81%) patients. Cirrhosis at month 18 was observed in ten (10%) patients in the standard group and one (1%) in the reinforced group (p=0.004).

CONCLUSIONS

The standard regimen of interferon, in chronic hepatitis C, confers a minimal sustained response rate at 18 months and may not prevent the occurrence of cirrhosis. Reinforced regimens allow sustained response to be reached in a limited number of patients and reduce the risk of cirrhosis during 18 months of follow-up.

Stability of hepatitis C virus RNA during specimen handling and storage prior to NASBA amplification

The influence of different anticoagulants and pre-amplification storage conditions on the stability of hepatitis C virus (HCV)-RNA, as detected by the quantitative HCV NASBA assay (NASBA-QT), was studied. The HCV-RNA load remained stable for at least 15 months when serum or plasma samples (EDTA and heparin) were directly frozen at -70 degrees C in lysis buffer. At 4 degrees C, the HCV-RNA load in serum or plasma stored with lysis buffer did not decline for at least 14 days. At 30 degrees C, however, the load declined significantly after 7 days. When clotted, whole blood was stored at 4 degrees C, the HCV-RNA load was stable for 72 h. However, when EDTA-anticoagulated whole blood was stored at 4 degrees C, the HCV-RNA load declined significantly after 48 h. In paired plasma and serum samples at baseline the HCV-RNA levels were similar. Heparin did not influence the efficiency of the HCV NASBA-QT assay. Clotted blood as well as EDTA or heparin anticoagulated blood can be used for quantifying HCV-RNA using the NASBA-QT assay. Blood samples should be stored at 4 degrees C after collection and serum or plasma separated within 24 h. Preferably, after separation, samples should be frozen in lysis buffer at -70 degrees C until NASBA-QT analysis.

Risk factors for hepatocellular carcinoma and its incidence after interferon treatment in patients with chronic hepatitis C. Osaka Liver Disease Study Group

To elucidate the risk factors for liver carcinogenesis and to examine the incidence of hepatocellular carcinoma (HCC) after interferon therapy, 1,022 chronic hepatitis C patients treated with interferon were followed by ultrasonography for 13 to 97 months (median 36 months). Sustained response with prolonged alanine aminotransferase normalization was found in 313 patients, transient response with alanine aminotransferase relapse after therapy in 304, and no response in 405. Forty-six developed HCC, of whom 5 were sustained responders, 9 were transient responders, and 32 were nonresponders. The cumulative incidence of HCC in transient responders was almost equal to that in sustained responders, and it was significantly higher in nonresponders than in sustained and transient responders (P=.0009). The seventh-year cumulative incidence rates of HCC in sustained responders, transient responders, and nonresponders were estimated to be 4.3%, 4.7%, and 26.1%, respectively. However, there was no significant difference in the cumulative incidence of HCC between patients with HCV subtype 1 and 2 (P=.14). Cox regression analysis showed that the risk of HCC development was not elevated in transient responders compared with sustained responders, but that the risk was 7.90-fold higher in nonresponders than in sustained responders (P=.008). Patients > or =55 years of age had a significantly higher risk ratio (4.65) than did those under 55 years of age (P=.006). The risk of HCC development in men was 4.35 times higher than the risk in women (P=.02). However, the degree of fibrosis was not a significant risk factor for the development of HCC (risk ratio, 3.16; P=.052). These results suggest that patients in the high-risk group of HCC after interferon therapy were those who showed no response, those who were older, and those who were male, and that such patients should be carefully followed using ultrasonography.

Comparison of two interferon alfa treatment regimens characterized by an early virological response in patients with chronic hepatitis C

OBJECTIVE

We investigated the efficacy of an interferon regimen characterized by an early virological response in patients with chronic hepatitis C and evaluated whether the patient's virological status during therapy would be useful for predicting a complete response.

METHODS

We treated 62 patients with chronic hepatitis C with 6 million units (MU) of human lymphoblastoid interferon daily for 4 wk. The serum HCV RNA was assayed at week 2 by the reverse transcription-polymerase chain reaction. HCV RNA-negative patients (group A) received 6 MU of interferon three times weekly for an additional 22 wk (total dose, 564 MU). HCV RNA-positive patients were randomly assigned to group B-1, which received the same regimen as group A, or to group B-2, which received 6 MU of interferon daily for 4 wk followed by 6 MU three times weekly for 18 wk (total dose, 660 MU).

RESULTS

Complete responses were achieved by 19 (63.3%) of 30 group A patients, compared with one (6.3%) of 16 group B-1 patients and none of 16 group B-2 patients. The virological response at week 2 and the pretreatment serum HCV RNA level were independent significant predictors of a complete response.

CONCLUSION

Patients who were still HCV RNA-positive at week 2 were unlikely to achieve a complete response after interferon therapy. An increase in the total dose of interferon failed to yield further benefit in these patients.

Durability of serological remission in chronic hepatitis C treated with interferon-alpha-2B

OBJECTIVE

We assessed the long-term effect of a course of interferon therapy on the biochemical and virological markers of Canadian patients with chronic hepatitis C.

METHODS

Thirty-six patients with chronic hepatitis C were treated with a median total dose of interferon-alpha-2B of 181.0 million U (range 109.0-384.0 million U) and were followed for a median of 37.2 months (range 12.0-94.2 months) after completing treatment. All patients received an initial 16 wk of interferon at a dose of 3 million U three times weekly; this was followed by either no further interferon or by 8 wk more at doses ranging from 1.5 to 10.0 million U three times weekly. Serum alanine aminotransferase (ALT) and hepatitis C virus (HCV) RNA levels were measured before interferon therapy, 6 months after treatment, and at the end of follow-up for each patient. HCV RNA was analyzed by branched DNA 1.0 assay and, if undetectable, by polymerase chain reaction. HCV genotyping was performed on serum samples.

RESULTS

Five (13.6%) of the 36 patients had a sustained treatment response, defined as normal ALT and undetectable viremia 6 months after treatment. All five patients remained in serological remission to the end of their follow-up, a median of 48.2 months (range 23.0-66.2 months) after interferon therapy. Responders were similar to nonresponders in age, gender, initial ALT and serum HCV RNA levels, pretreatment histology, and total dose of interferon received.

CONCLUSIONS

In patients with chronic hepatitis C, 13.6% had normal ALT and undetectable serum HCV RNA 6 months after finishing interferon therapy. These patients remained in serological remission to the end of their follow-up, 48.2 months after interferon therapy.

Prolonged treatment (2 years) with different doses (3 versus 6 MU) of interferon alpha-2b for chronic hepatitis type C. Results of a multicenter randomized trial

BACKGROUND/AIMS

To examine the effect of prolonged treatment with different doses of interferon alpha-2b on the relapse rate in patients with chronic hepatitis C.

METHODS

One hundred and seventy-one patients with non-cirrhotic chronic hepatitis C were enrolled in an Italian multicenter trial. All patients were treated for 3 months with 3,000,000 Units (3 MU) of interferon alpha-2b given subcutaneously three times a week (t.i.w.). Patients with abnormal alanine aminotransferase (ALT) values were given 6 MU of interferon for an additional 3 months. If ALT remained persistently abnormal, therapy was then suspended. If ALT levels were normal, therapy was continued (6 MU t.i.w.) for an additional 18 months (total=2 years). Patients with normal ALT were randomly assigned to two groups, one receiving 3 MU and the other receiving 6 MU t.i.w. for an additional 21 months (total=2 years). Follow-up continued for 2 years after therapy withdrawal.

RESULTS

Seven patients stopped treatment during the first 3 months. Of the remaining 164 patients, 76 (46%) showed abnormal ALT levels after 3 months of therapy: 11 of these (14%) normalized ALT values when given 6 MU and a sustained response was maintained in eight during the follow-up. Overall, 54 and 34 patients were allocated respectively to the groups receiving the 3 MU and 6 MU long-term treatment. At the end of therapy, 35/54 patients of the group 3 MU and 21/34 patients of the group 6 MU showed normal ALT levels (65% vs 62%, p=N.S.). After 2 years of follow-up, 24/35 (69%) patients of the group 3 MU and 16/21 (76%) of the group 6 MU were still in remission (p=N.S.). In an intention-to-treat analysis, 48/171 (28%) patients showed a long-term response (normal ALT values, HCV-RNA negative). About 65% of the sustained responders showed low baseline viremia compared with 33% of non-responders (p=0.005) while genotype 1b was more frequently found among non-responders than in long-term responders (84% vs 25%, p=0.0001).

CONCLUSIONS

About 14% of patients who do not respond to a 3-month course of 3 MU of interferon normalize ALT levels when given 6 MU. In prolonged treatment, there is no significant difference between 3 and 6 MU in inducing a sustained response. Patients with low baseline viremia and genotype 2a respond significantly better to prolonged interferon therapy than highly viremic patients with genotype 1b.

[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.

Distribution of hepatitis C virus genotypes in German patients with chronic hepatitis C: correlation with clinical and virological parameters

BACKGROUND/AIMS

The hepatitis C virus genotypes have been shown to be differently distributed between distinct geographical areas and to be associated with different clinical presentations. In the present study we investigated the distribution of HCV genotypes in 379 German patients with chronic hepatitis C in relation to age, sex, route of infection, liver histology and viremia.

METHODS

Typing of HCV was done using restriction fragment length polymorphism analysis as well as a DNA enzyme immunoassay. HCV RNA concentrations were determined by quantitative polymerase chain reaction. Liver biopsies were performed in 187 patients and the histological activity was graded by the Knodell score.

RESULTS

Seventy percent were infected with genotype 1 (20% subtype 1a, 80% subtype 1b), 4% with genotype 2 and 26% with genotype 3 (all subtype 3a). Genotype 3a and 1a infection was significantly associated with intravenous drug abuse. In contrast, genotype 1 predominated in patients with post-transfusion hepatitis and infection of unknown origin. A changing relative prevalence of HCV genotypes in relation to age was also observed. Patients with genotype 3 infection showed significantly lower HCV RNA levels and a lower mean histological activity score as compared to patients with genotype 1 and genotype 2. However, using multivariate analysis, only age and mode of transmission but not histological activitiy score were shown to be independent variables.

CONCLUSIONS

Our study confirms previous reports from other countries that HCV variants can be classified into a relatively small number of discrete genotypes, and that the subtype 1b clearly predominates. However, we found evidence that there is a changing relative prevalence of HCV genotypes in relation to age, and that the mode of transmission is reflected in the predominance of certain genotypes.

Circulating matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 as serum markers of fibrosis in patients with chronic hepatitis C. Relationship to interferon response

BACKGROUND/AIMS/METHODS

The imbalance between matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) is considered to be an important determinant of extracellular matrix deposition and breakdown. We measured serum MMP-1, MMP-2, TIMP-1 and TIMP-2 levels using the respective one-step sandwich enzyme immunoassays in 98 patients with chronic hepatitis C treated with interferon beta to examine their clinical significance for assessment of liver histology and to determine whether they can be useful as predictors of the interferon response.

RESULTS

Serum TIMP-1 levels showed a positive correlation with the degree of fibrosis (r(s)=0.30, p= 0.004). Serum MMP-2 levels revealed positive relationships with the degree of periportal necrosis (r(s)= 0.32, p=0.002), the degree of fibrosis (r(s)=0.26, p= 0.01) and total score of histological activity index (r(s)=0.24, p=0.02). Serum MMP-2 levels were significantly higher in patients with no response than in those with sustained and transient response (p<0.01 and p<0.05, respectively), while serum MMP-1 levels did not differ among the three groups. Compared with the levels in sustained responders, the total amounts of serum TIMP-1 were significantly lower in transient responders and non-responders (p<0.01 and p<0.001, respectively). As for serum TIMP-2 levels, a significant decrease was found in transient responders and non-responders (p<0.01). The ratios of serum MMP-2 to TIMP-1 levels were significantly higher in transient responders and non-responders than in sustained responders (p<0.001, respectively) even when HCV RNA levels were low in patients with HCV genome subtype 1b or when the HCV genome subtype was 2a or 2b. Sustained response was never found in type 1b patients with ratios of serum MMP-2 to TIMP-1 levels of over 6.0. In logistic multivariate regression analysis, the ratios of serum MMP-2 to TIMP-1 level (p=0.0001), HCV genome subtype (p=0.005) and serum TIMP-2 level (p=0.03) were the independent predictors for sustained response, while serum MMP-2 level (p=0.0006) was the only predictor for no response.

CONCLUSIONS

Serum MMP-2 and TIMP-1 levels might be useful for estimating the degree of liver fibrosis. The ratio of serum MMP-2 to TIMP-1 levels may serve as a new predictor of interferon response in patients with chronic hepatitis C.

Quasispecies nature of hepatitis C virus and response to alpha interferon: significance as a predictor of direct response to interferon

BACKGROUND/AIMS

We evaluated the significance of the quasispecies nature of HCV as a predictor of the response to alpha interferon therapy in patients with chronic hepatitis C.

METHODS

Natural alpha interferon was administered in 62 patients for 24 weeks (daily for 2 weeks, then three times weekly for 22 weeks) and factors were analyzed that could affect the response. HCV subtype, HCV RNA concentrations and the number of HCV quasispecies were evaluated before treatment. HCV RNA concentrations were measured by branched DNA probe assay. The number of HCV quasispecies was measured by fluorescence single-strand conformation polymorphism analysis.

RESULTS

The HCV RNA concentration (p < 0.0001), HCV subtype (p = 0.0076), and the number of HCV quasispecies (p = 0.0024) were significantly associated with a complete response. Multivariate analyses showed that the number of HCV quasispecies was an independent predictor of the disappearance of HCV RNA during the administration of alpha interferon, but did not predict a relapse after its completion. Pretreatment concentration of HCV RNA was the only factor that was related to a long-term disappearance of HCV RNA.

CONCLUSIONS

The number of HCV quasispecies was significantly related to the response to alpha interferon early in its administration. The pretreatment concentration of HCV RNA was mainly related to a relapse following completion of treatment.

Morbidity and mortality of recurrent hepatitis C infection after orthotopic liver transplantation

Through molecular virological testing it is now clear that HCV reinfection of the allograft is virtually universal in liver transplant recipients. Although histopathological recurrence of hepatitis C occurs in the majority of patients, it is absent in a substantial minority. To date, no prognostic factors, other than genotype 1b, have been identified that accurately predict these dissimilar outcomes. The natural history of recurrent hepatitis C varies. Historically, it has been regarded as generally benign. However, with increasing numbers of patients transplanted for hepatitis C it is now clear that a subgroup of patients develops severe progressive cholestatic hepatitis associated with allograft failure and death without retransplantation. Within 5 years following OLT, approximately 15-20% of patients progress to chronic active hepatitis and another 15-20% become cirrhotic. A minority of patients develop glomerulopathy or vasculitis, which are often associated with cryoglobulinaemia. The impact of immunosuppressive medications and rejection episodes on histopathological recurrence of progressive hepatitis C remains controversial and requires further studies. Although actuarial survival rates of patients transplanted for hepatitis C differ among transplantation centres, it appears that histopathological recurrence of hepatitis C does have an adverse impact on actuarial survival compared to the survival of patients transplanted for autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis and metabolic liver diseases. When allograft failure develops in patients with recurrent hepatitis C, retransplantation is indicated, even though recent reports indicate that mortality may be increased, especially with concurrent renal insufficiency.

Duration of HCV infection as a predictor of nonresponse to interferon

Duration of hepatitis C virus (HCV) infection is a key feature in determining responsiveness to interferon (IFN). Studies assessing its value as a predictive factor in chronic HCV infection show that a long duration of infection reduces the likelihood of a sustained response to IFN (defined as ALT normalization and clearance of serum HCV-RNA). The effect of HCV infection duration is independent of the presence of cirrhosis and level of HCV viremia. Meta-analysis of IFN trials in acute HCV infection shows an obvious effect of the drug on long-term ALT normalization and HCV-RNA clearance. Treatment of HCV infection during the acute or early chronic phase could therefore maximize therapeutic effectiveness.

Predictive factors of a response to interferon therapy in chronic hepatitis C

To determine predictive factors of response to interferon (IFN) therapy in chronic hepatitis C patients, we administered IFN-alpha, 1 6 million U1 intramuscularly daily for 2 consecutive weeks, then three times a week, to 136 patients judged to have chronic hepatitis C virus (HCV) infection according to HCV-RNA positivity. We also investigated the most effective length of IFN-alpha treatment according to efficacy factors, i.e., histological activity index. HCV-RNA genotype, and HCV-RNA levels. patients were classified either into a short-term group (entire treatment period 16 weeks), standard-term group (24 weeks), and long-term group (40 weeks). Patients were assessed as complete responders (CR) if their HCV-RNA became negative and their alanine aminotransferase (ALT) decreased to < or = 39 IU/L after 18 months of treatment or nonresponders in other cases. Results showed that HCV-RNA levels and genotype were statistically significant predictive factors. CR rates in the standard- and long-term groups were significantly higher than in the short-term group (p < 0.05). In patients with low HAI scores, the long-term group showed the highest CR rate. In patients with low virus counts, the CR rate increased to 73% in the 24th week and 100% in the 40th week. CR rates in patients with HCV-RNA genotype 1b and 2a or 2b also increased as the treatment period became longer. For efficacy, a 24-week treatment period was necessary. In patients with mild liver tissue damage or low virus counts, 40 weeks of treatment proved highly useful.

A long-term follow-up study of interferon treatment for chronic hepatitis C in Japanese patients with congenital bleeding disorders

Twenty-one HIV negative Japanese patients with chronic hepatitis C who had congenital bleeding disorders, 15 hemophilia A, 3 hemophilia B, 1 von Willebrand's disease, 1 afibrinogenemia and 1 thrombasthenia, were treated with 9 million units 3 times a week of natural interferon (IFN)-alpha for 6 months. They were followed, biochemically and virologically, for at least 18 months after therapy discontinuation to evaluate the long-term results. Liver biopsy, hepatitis C virus (HCV) genotyping and quantification of viral load by polymerase chain reaction (PCR) were performed to identify the predictors of a favorable response to IFN treatment. One male patient with hemophilia A dropped out because of general fatigue and was excluded from evaluation. Ten (50.0%) patients continued to be HCV RNA negative in serum together with normal ALT levels throughout the study. Subtype 1b and a high level of viremia significantly associated with an unfavorable outcome on the response to IFN although liver histology was not definitive for predicting the response. We concluded that a 6-month treatment with high doses of natural IFN-alpha was effective in inducing a long-term response without relapse of viremia in 50% of chronic hepatitis C patients with congenital bleeding disorders and that HCV subtype and pretreatment level of viremia were useful predictors of the response to IFN in treating such patients.

Pathogenesis of chronic hepatitis C and associated clinical manifestations

In 20% of patients exposed to hepatitis C virus, infection is transient but, after a few months, the patient remains susceptible to infection with the same strain. Protective immunity is short-lived. This suggests that recovery is related to the cellular immune response, which presumably lyses infected cells, and that the need during recovery for a virus-neutralizing anti-envelope response, is transient. In 80% of patients the infection is persistent, and it seems that antigenic variation of the envelope proteins allows the virus to escape neutralization by anti-envelope responses. The fact that this antigenic variation occurs at a much lower rate in agammaglobulinaemic subjects suggests that the major immune pressure producing this variation is humoral. How the virus-infected cells avoid lysis by cytotoxic T cells, which can be demonstrated in small numbers in the infected liver, remains unclear. The recent observation, that HCV infects CD8 lymphocytes, raises the possibility that virus infection of CD8 cells may impair their function and contribute to persistent infection. The mechanisms of production of cryoglobulin and of autoantibody formation are both unclear.

Long-term outcome of hepatitis C infection after liver transplantation

BACKGROUND

End-stage cirrhosis related to hepatitic C virus (HCV) is a common reason for liver transplantation, although viremia ia known to persist in most cases. We investigated the impact of persistent HCV infection after liver transplantation on patient and graft survival and the effects of the HCV genotype and the degree of HLA matching between donor and recipient on the severity of recurrent hepatitis.

METHODS

A group of 149 patients with HCV infection who received liver transplants between January 1982 and April 1994 were followed for a median of 36 months; 623 patients without HCV infection who underwent liver transplantation for end-stage chronic liver disease were used as a control group. A total of 528 liver-biopsy specimens from the HCV-infected recipients were reviewed, including 82 obtained one year after transplantation as scheduled and 39 obtained at five years as scheduled. In addition, biopsy specimens were obtained from 91 of the HCV-negative patients five years after transplantation.

RESULTS

Cumulative survival rates for the 149 patients with HCV infection were 79 percent after one year, 74 percent after three years, and 70 percent after five years, as compared with rates of 75 percent, 71 percent, and 69 percent, respectively, in the HCV-negative transplant recipients (P=0.12). Of the 130 patients with hepatitis C infection who survived more than 6 months after transplantation, 15 (12 percent) had no evidence of chronic hepatitis on their most recent liver biopsy (median followup, 20 months), 70 (54 percent) had mild chronic hepatitis (median, 35 months), 35 (27 percent) had moderate chronic hepatitis (median, 35 months), and 10 (8 percent) had cirrhosis (median, 51 months). Graft loss occurred after a median of 303 days in 27 of the 149 patients, including 5 with HCV-related cirrhosis and 3 with HCV-related cholestatic hepatitis. Infection with HCV genotype 1b was associated with more severe graft injury, whereas the primary immunosuppressive regimen used and the extent of HLA mismatching between donors and recipients had no significant effect on this variable.

CONCLUSIONS

After liver transplantation for HCV-related cirrhosis, persistent HCV infection can cause severe graft damage, and such damage is more frequent in patients infected with HCV genotype 1b than with other genotypes. After five years, the rates of graft and overall survival are similar between patients with and those without HCV infection.