Treatment of hepatitis C patients with normal aminotransferases levels

Acute Liver Damage Associated with Innate Immune Activation in a Small Nonhuman Primate Model of Hepacivirus Infection

Despite its importance in shaping adaptive immune responses, viral clearance, and immune-based inflammation, tissue-specific innate immunity remains poorly characterized for hepatitis C virus (HCV) infection due to the lack of access to acutely infected tissues. In this study, we evaluated the impact of natural killer (NK) cells and myeloid (mDCs) and plasmacytoid (pDCs) dendritic cells on control of virus replication and virus-induced pathology caused by another, more rapidly resolving hepacivirus, GB virus B (GBV-B), in infections of common marmosets. High plasma and liver viral loads and robust hepatitis characterized acute GBV-B infection, and while viremia was generally cleared by 2 to 3 months postinfection, hepatitis and liver fibrosis persisted after clearance. Coinciding with peak viral loads and liver pathology, the levels of NK cells, mDCs, and pDCs in the liver increased up to 3-fold. Although no obvious numerical changes in peripheral innate cells occurred, circulating NK cells exhibited increased perforin and Ki67 expression levels and increased surface expression of CXCR3. These data suggested that increased NK cell arming and proliferation as well as tissue trafficking may be associated with influx into the liver during acute infection. Indeed, NK cell frequencies in the liver positively correlated with plasma (R = 0.698; P = 0.015) and liver (R = 0.567; P = 0.057) viral loads. Finally, soluble factors associated with NK cells and DCs, including gamma interferon (IFN-γ) and RANTES, were increased in acute infection and also were associated with viral loads and hepatitis. Collectively, the findings showed that mobilization of local and circulating innate immune responses was linked to acute virus-induced hepatitis, and potentially to resolution of GBV-B infection, and our results may provide insight into similar mechanisms in HCV infection.

IMPORTANCE

Hepatitis C virus (HCV) infection has created a global health crisis, and despite new effective antivirals, it is still a leading cause of liver disease and death worldwide. Recent evidence suggests that innate immunity may be a potential therapeutic target for HCV, but it may also be a correlate of increased disease. Due to a lack of access to human tissues with acute HCV infection, in this study we evaluated the role of innate immunity in resolving infection with a hepacivirus, GBV-B, in common marmosets. Collectively, our data suggest that NK cell and DC mobilization in acute hepacivirus infection can dampen virus replication but also regulate acute and chronic liver damage. How these two opposing effects on the host may be modulated in future therapeutic and vaccine approaches warrants further study.

A 24-week course of high-dose interferon-alpha plus ribavirin for Taiwanese chronic hepatitis C patients with persistently normal or near-normal alanine aminotransferase levels

BACKGROUND/AIMS

We aimed to evaluate the efficacy, advantage, and safety of a 24-week regimen with high-dose interferon-alpha (INF-alpha; 6 million units thrice weekly) plus ribavirin (1000-1200 mg/day) combination therapy for 46 Taiwanese chronic hepatitis C (CHC) patients with persistently normal or near-normal alanine aminotransferase (PNALT) levels.

METHODS

Ninety-two age- and sex-matched CHC patients with elevated ALT levels (> 2 times the upper limit of normal range) with a ratio of 1:2, treated with the same regimen, served as a control.

RESULTS

The sustained virologic response (SVR) rate was comparable between PNALT (67.4%) and elevated ALT (65.2%) groups (intention-to-treat analysis). The two groups had similar rates of discontinuation and incidence of adverse effects. Viral genotype 1b, baseline viral loads, body mass index, and age were significant factors negatively associated with SVR. Further decline of ALT levels throughout the follow-up period was observed in sustained responders of the PNALT group. None of the eight patients with ALT flares developed icteric hepatitis. The virologic efficacy was sustained in a 3-year extended follow-up period.

CONCLUSION

high-dose INF-alpha with ribavirin combination therapy is effective, safe, and well tolerated in CHC patients with PNALT levels. The ALT assay might not be used as a single biochemical marker for determination of treatment consideration.

Review article: management of patients with chronic hepatitis C virus infection and "normal" alanine aminotransferase activity

BACKGROUND

Hepatitis C virus infection, a major cause of chronic liver disease, occurs with normal serum alanine aminotransferase activity in approximately 25% of patients. These patients have historically remained untreated but substantial evidence indicates liver damage, progression of disease and impaired quality of life in some individuals.

AIM

To review the current management of patients with chronic hepatitis C and normal alanine aminotransferase activity.

METHODS

This review represents the summary of discussions at a Clinical Workshop with a comprehensive literature searching of available databases (PubMed and Embase).

RESULTS

Current limits defining normal serum alanine aminotransferase activity are not representative of a "healthy" status. Most patients with hepatitis C and normal alanine aminotransferase levels have histologically proven liver damage that, although generally mild, may be significant (> or =F2) in up to 20% of patients and progresses at approximately 50% of the rate in patients with elevated alanine aminotransferase levels. Some patients have persistently normal alanine aminotransferase activity and may have a more benign outcome, but a significant proportion (> or =20%) experience periods of increased serum alanine aminotransferase activity which may be associated with enhanced disease progression.

CONCLUSIONS

A treatment approach that considers host and virus-related variables and optimizes patient and cost benefits may therefore provide more effective management of patients with chronic hepatitis C and normal alanine aminotransferase activity.

Hemophilic siblings with chronic hepatitis C: Familial aggregation of spontaneous and treatment-related viral clearance

BACKGROUND & AIMS

Hemophilic siblings provide a unique population to explore the natural history of chronic hepatitis C.

METHODS

From 3993 hemophilic patients with hepatitis C, 257 sibling pairs, of which both members had evidence of hepatitis C infection, were studied to evaluate the genetic contribution to spontaneous and treatment-induced clearance of hepatitis C infection and progression of liver disease. Familial aggregation was assessed by comparing observed probabilities of concordance for these disease characteristics within sibling pairs to those expected for randomly paired hemophilic subjects. Additional measures of familial aggregation, heritability, and sibling relative risk were also calculated.

RESULTS

Among human immunodeficiency virus-negative subjects, concordance for spontaneous viral clearance was 2-fold higher in siblings compared with randomly paired subjects (8.8% vs 4.3%, respectively, P = .04). Similarly, the concordance rate for treatment-related viral clearance was over twice that among sibling pairs than among randomly paired hemophiliacs (31.3% vs 13.3%, respectively, P = ns). Heritability estimates for spontaneous and treatment-induced viral clearance were 0.24 +/- 0.14 (P = .04) and 0.43 +/- 0.42 (P = .10), respectively. The sibling relative risks for these respective characteristics were 1.6 and 1.7. Concordance for advanced liver disease was higher among siblings but did not reach statistical significance (4.0% vs 2.3%, respectively, P = ns). The heritability estimate was 0.29 +/- 0.13 (P = .02).

CONCLUSIONS

Concordance rates and heritability estimates for spontaneous and treatment-related viral clearance indicate that genetic factors have a modest influence on the outcome of hepatitis C, although shared environmental factors cannot be excluded. Investigations to map candidate disease-susceptibility genes associated with these characteristics must be approached with caution.

Is alanine aminotransferase a good marker of histologic hepatic damage in renal transplant patients with hepatitis C virus infection?

INTRODUCTION

Renal transplant (RTx) patients with hepatitis C frequently show normal levels of alanine aminotransferase (ALT) and the significance of ALT in this group has not been established.

AIM

To determine the value of ALT as a marker of histologic hepatic damage in RTx patients with hepatitis C virus (HCV) infection.

MATERIALS AND METHODS

HCV-RNA-positive RTx patients with a liver biopsy were analyzed regarding staging and the grading of periportal and lobular necroinflammatory activity. Spearman's correlation coefficient was used to determine the correlation between ALT and histologic variables. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) of ALT in the detection of septal fibrosis and interface hepatitis, and/or confluent necrosis were calculated.

RESULTS

Fifty-three patients (32 men, 60%), with a mean age of 42 +/- 10 yr and time since transplant of 5 +/- 4 yr were included. Only 27 (51%) patients showed elevated ALT levels, which were associated with septal fibrosis (p = 0.001), interface hepatitis (p < 0.001) and confluent necrosis (p = 0.05). A correlation was observed between ALT and staging (r = 0.50, p < 0.001), periportal necroinflammatory activity (r = 0.59, p < 0.001) and lobular necroinflammatory activity (r = 0.50, p < 0.001). The sensitivity, specificity, PPV and NPV of ALT were 92, 61, 41 and 96%, respectively, for the detection of septal fibrosis, and 87, 77, 74 and 88% for the detection of interface hepatitis and/or confluent necrosis.

CONCLUSION

ALT is a good marker of histologic hepatic lesion in HCV-infected RTx patients and, therefore, liver biopsy can be avoided in patients with persistently normal ALT.

Daily Interferon Monotherapy for Chronic Hepatitis C in Patients with Normal or Near-normal Serum Alanine Transaminase Levels: A Comparison of Two Protocols

OBJECTIVES

Up to 30% of the 5 million patients with chronic hepatitis C in the United States have normal serum alanine transaminase (ALT) levels. These individuals have not been treated aggressively, and reported response rates have been low. No study has targeted patients treated in a community practice setting.

METHODS

Consecutive patients with chronic hepatitis C with normal or near-normal serum ALT levels seen over a 2-year period in a community gastroenterology-hepatology practice were randomly assigned to receive either 3 MU or 6 MU daily interferon (IFN)-alpha-2a monotherapy for 12 months.

RESULTS

Sixteen patients (8 in each treatment arm) qualified for study. End-of-treatment response was 87.5% with 6 MU IFN daily and 75% with 3 MU IFN daily, whereas sustained virologic response was 62.5% and 50%, respectively. Genotype 1 patients had an improved outcome with the higher 6 MU dose.

CONCLUSIONS

Daily IFN monotherapy achieves high response rates in patients with chronic hepatitis C with normal or near-normal ALT. Present-day pegylated interferon regimes can be expected to be as effective.

Viral clearance in HCV viraemic patients with normal alanine aminotransferase after combination therapy: a controlled, open-labelled study

BACKGROUND

In patients with chronic hepatitis C virus infection and persistently normal alanine aminotransferase levels, liver fibrosis has been reported in 0-22% of cases and advanced liver disease in 5-10% of cases.

AIM

To determine whether patients with persistently normal alanine aminotransferase levels clear infection after anti-viral therapy at equal or different rates from infected patients with raised alanine aminotransferase levels.

METHODS

Thirty-five hepatitis C virus RNA-positive patients with fibrosis at liver histology (Group 1) were matched for genotype, sex, age and histology with patients with raised alanine aminotransferase levels (Group 2). Both groups were treated with 3 MU interferon-alpha2b plus ribavirin (1000-1200 mg) for 12 months.

RESULTS

End-of-therapy response was achieved in 71.4%[95% confidence interval (CI), 56.4-86.3] of patients in Group 1 and in 52.3% (95% CI, 42.8-61.9) of those in Group 2 (P = 0.04). At week 72, 22 patients (62.8%; 95% CI, 46.8-78.1) in Group 1 and 50 patients (47.5%; 95% CI, 38.0-57.1) in Group 2 showed a sustained virological response (P = 0.11). Non-1 genotype was the only independent predictor of sustained response (P = 0.002), with an odds ratio of 3.45 (95% CI, 1.58-7.50). At month 3 of therapy, the positive predictive values for non-response were 100% and 96% in Groups 1 and 2, respectively.

CONCLUSIONS

Interferon and ribavirin induce comparable sustained virological response in patients with persistently normal or raised alanine aminotransferase levels. Stage 1 fibrosis, rather than alanine aminotransferase levels, may be the criterion on which to decide whether or not to treat patients with persistently normal alanine aminotransferase levels.

Dynamics of alanine aminotransferase during hepatitis C virus treatment

Studies of the kinetics of hepatitis C virus (HCV) decline during interferon (IFN)-based therapy have led to insights into treatment efficacy. However, the kinetics of serum alanine aminotransferase (ALT), an enzyme used as a surrogate of liver damage, have not been closely monitored, and it is not known if they correlate with those of HCV RNA. Here we describe the associations between ALT and HCV dynamics. We analyzed 35 patients treated daily with 10 mIU IFN-alpha 2b with or without ribavarin for 28 days followed by standard IFN/ribavirin therapy. Patients exhibited 4 patterns of ALT change: (1) exponential decay of ALT, (2) transient increase in ALT followed by a decrease to pretreatment or normal levels, (3) increase in ALT to a new level, and (4) no significant change. By simultaneously modeling HCV and ALT dynamics, we successfully fit the observed changes. We found ALT decays with t(1/2) = 12.7 hours. The transient increase in ALT observed in some patients suggested a mild hepatotoxic effect of IFN. However, patients with a smaller initial ALT increase achieved higher rates of viral negativity by week 72 (P =.02). The week-4 ALT decline correlated with the HCV log drop (P =.006) and the efficacy of therapy (P =.025). In conclusion, our results suggest the use of ALT as a surrogate marker for treatment effect in patients with elevated ALT.

Combination treatment of IFNalpha2b and ribavirin in patients with chronic hepatitis C and persistently normal ALTs

Combination therapy of interferon-alpha2b and ribavirin was prospectively evaluated in 20 patients with chronic replicative hepatitis and persistently normal ALTs. Patients with normal ALTs on three or more occasions within 6 months received interferon-alpha2b 3 MU three times a week with ribavirin 1000-1200 mg everyday for 12 months and had a follow-up of 6 months. HCV genotype 1 was found in 16, and HCV genotype 2 or 3 in 4 patients. No patient experienced an ALT elevation during therapy. Ten of 20 patients (50%) cleared virus at the end of treatment. In an intent-to-treat analysis, a sustained virological response (SR) was achieved in 8 of 20 patients (40%). Nonresponse occurred in 5 patients. Relapse and breakthrough were seen in 2 patients each. Treatment was discontinued in 3 patients due to side effects. Interferon (IFN) ribavirin combination therapy is effective in patients with normal ALTs and appears superior to IFN monotherapy.

Natural history of chronic hepatitis C

Much controversy surrounds the issue of the natural history of hepatitis C virus (HCV) infection. Many authorities view the disease as inexorably progressive with a high probability of advancing over time to cirrhosis and occasionally hepatocellular carcinoma (HCC) and, therefore, likely to be responsible for causing death. Others regard chronic hepatitis C as having a variable outcome, the majority of infected persons not dying from the disease, but more likely from the comorbid conditions that so often accompany infection by this agent, or from more common medical conditions. Disagreements probably derive from the manner of conduct of the study and the populations studied. Efforts to determine natural history are handicapped by the primary characteristics of the disease, namely that its onset rarely is recognized and its course is prolonged exceedingly. Thus, different outcomes have come from retrospective rather than from prospective studies, but both have concluded that at least 20% of chronically infected adults develop cirrhosis within 20 years. More recent studies that used a retrospective/prospective approach, focusing largely on young infected individuals, have produced different results. Among these young people, particularly young women, spontaneous resolution of the viral infection is more common than previously thought and cirrhosis has been identified in 5% or fewer of them. The major failing for all groups studied, young and old, is that natural history studies have rarely exceeded the first 2 decades, so that outcome beyond this time is not known, other than through modeling. Several host-related and extraneous factors probably affect the natural history.

Natural history of chronic hepatitis C

Much controversy surrounds the issue of the natural history of hepatitis C virus (HCV) infection. Many authorities view the disease as inexorably progressive with a high probability of advancing over time to cirrhosis and occasionally hepatocellular carcinoma (HCC) and, therefore, likely to be responsible for causing death. Others regard chronic hepatitis C as having a variable outcome, the majority of infected persons not dying from the disease, but more likely from the comorbid conditions that so often accompany infection by this agent, or from more common medical conditions. Disagreements probably derive from the manner of conduct of the study and the populations studied. Efforts to determine natural history are handicapped by the primary characteristics of the disease, namely that its onset rarely is recognized and its course is prolonged exceedingly. Thus, different outcomes have come from retrospective rather than from prospective studies, but both have concluded that at least 20% of chronically infected adults develop cirrhosis within 20 years. More recent studies that used a retrospective/prospective approach, focusing largely on young infected individuals, have produced different results. Among these young people, particularly young women, spontaneous resolution of the viral infection is more common than previously thought and cirrhosis has been identified in 5% or fewer of them. The major failing for all groups studied, young and old, is that natural history studies have rarely exceeded the first 2 decades, so that outcome beyond this time is not known, other than through modeling. Several host-related and extraneous factors probably affect the natural history.

Predictive value of ALT levels for histologic findings in chronic hepatitis C: a European collaborative study

The aim of this retrospective study was to determine the predictive value of alanine aminotransferase (ALT) levels for histologic findings in patients with chronic hepatitis C virus (HCV) infection. Data on 864 HCV RNA-positive patients were collected. ALT values were obtained at the time of biopsy (before treatment), and normal ALT values were defined as normal values obtained at serial evaluations during a 6-month period. Histologic results were scored using the METAVIR system. Among all patients, 99% of those with elevated ALT levels had a score of at least F1 (positive predictive value [PPV], 99%) and 88% had a score greater than A1F1. Among patients with persistently normal ALT values, 65% had a score of at least F1 (negative predictive value [NPV], 35%) and 26% had a score greater than A1F1. The receiver operating characteristics analysis indicates that the ALT threshold for the best compromise sensitivity-specificity was about 2.25 times the upper limit of normal (ULN). In conclusion, almost all HCV RNA-positive patients with elevated ALT levels have some degree of fibrosis. However, an important proportion of patients with persistently normal ALT levels also show some histologic signs of fibrosis; the degree of fibrosis is usually mild but is sometimes more marked, and in rare cases cirrhosis may be present. In this subset of patients, the indication of liver biopsy and the potential benefit of therapy need to be further evaluated. These results suggest the need to revisit the algorithm for liver biopsy practice.