Different outcomes of chronic hepatitis delta virus infection in woodchucks

Hepatitis delta virus (HDV) superinfection of woodchuck chronic carriers of woodchuck hepatitis virus (WHV) results in acute and chronic disease. The different courses of disease mimicked the outcome of human HDV superinfection, making woodchucks valuable models for clinical studies of HDV. Ten of 11 woodchuck chronic carriers of WHV superinfected with HDV developed acute HDV infection with markers of viral replication in the serum and liver. One animal (DW128) had no serological markers of acute HDV infection. Nine of 11 (82%) superinfected animals developed chronic HDV infection. An unusual course of chronic HDV infection occurred in one woodchuck (DW128): no serum markers of acute or chronic HDV infection appeared but HDV RNA was detected in the liver, indicating that chronic HDV infection can occur without serological markers.     

Antibodies to hepatitis C virus and chronic hypertransaminasemia in southern Italy.

In an ecographic survey for gallstones, executed on a systematic sample from the municipal electoral roll of a town in Southern Italy, 164 subjects were found with ALT more than twice the upper normal limit (unl). Five years later 138 of these were re-examined; 76 still had ALT greater than 2 unl (group A), 41 still abnormal (group B) and 21 normal (group C). Anti-HCV antibodies were found in 52 subjects of group A (68%). 18 of group B (44%) and 2 of group C (9.5%). The odds ratio of ALT greater than 2 unl (A vs C) in anti-HCV+ was 20.6 and of a still elevated ALT (A + B vs C) was 14.1. Logistic regression was used to eliminate the effect of possible confounding factors (sex, age, alcohol, drugs, HBV markers) on the relationship chronic ALT increase and anti-HCV positivity but the odds ratio was still 18.9 (A vs C) and 11 (A + B vs C). These findings suggest that anti-HCV antibodies are strongly associated with chronic hypertransaminasemia at the population level in Southern Italy.     

Dual chronic hepatitis B virus and hepatitis C virus infection

Dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are common in HBV or HCV endemic areas. However, several clinical and pathogenetic issues remain unresolved. First, clinical and in vitro studies suggest the interactions between two viruses. The dynamics of the interaction in untreated setting versus treated setting and its influence on the long-term outcomes await further studies. A key issue regarding viral interactions is whether modulation of infection occurs in the same dually infected individual hepatocyte of the liver. Clarifying this issue may help to understand the reciprocal interference between HCV and HBV and provide clues for future immunopathogenetic studies. Second, the prevalence and clinical significance of coexisting occult HBV infection in patients with chronic HCV infection need further investigations. Third, combination therapy of peginterferon alfa-2a and ribavirin appears to be just as effective and safe for the treatment of hepatitis B surface antigen (HBsAg)-positive patients chronically infected with active chronic hepatitis C as it is in patients with HCV monoinfection. Nevertheless, one-third of dually infected patients with nondetectable serum HBV DNA-level pretreatment developed HBV reactivation posttreatment. How to prevent and treat this reactivation should be clarified. Furthermore, about 10% of the dually infected patients lost HBsAg. Underlying mechanisms await further investigations. Finally, the optimal treatment strategies for dually infected patients with hepatitis B e antigen-positive chronic hepatitis B should be identified in future clinical trials.     

Predicting progression to cirrhosis in chronic hepatitis C virus infection

Summary. A systematic evaluation of published studies was undertaken to identify factors associated with accelerated fibrosis progression in patients with chronic hepatitis C virus (HCV) infection. An ecologic analysis was used to estimate relative risk (RR) of cirrhosis across four study methodologies: liver clinic series, post-transfusion cohorts, community-based studies and blood donor series. In each study category, the following factors were independently associated with disease progression: male sex (RR = 1.08); heavy alcohol consumption (RR = 1.61); elevated serum ALT levels (RR = 1.23) and histology demonstrating high-grade necro-inflammatory activity. After adjusting for these cofactors, older age at HCV infection and acquisition of HCV through blood transfusion were not implicated in influencing disease outcome. Although not able to be examined in this study,co-infection with HIV, and to a lesser extent HBV, is also likely to result in worse outcomes for patients with chronic HCV infection. Virological factors such as HCV genotype, viral load and quasispecies diversity are less likely to be important. A Weibull distribution was used to model disease progression at a population level. The influence of cofactors on individual prognosis was examined and an algorithm to predict the risk of subsequently developing cirrhosis is presented.     

Influence of hepatitis delta virus infection on progression to cirrhosis in chronic hepatitis type B

Serological markers of hepatitis delta virus (HDV) infection were found in 18 (12%) of 146 consecutive patients with chronic hepatitis B, and the characteristics of patients who had antibody to HDV (anti-HDV-positive) were analyzed. During one to 15 years of follow-up, histological deterioration was documented in 77% of anti-HDV-positive patients; however, in hepatitis B surface antigen (HBsAg) carriers without HDV infection, histology deteriorated in 30% but improved or remained unchanged in the majority of patients (P less than .01). In seven (70%) of the 10 anti-HDV-positive patients who showed transition from chronic active hepatitis to cirrhosis, this event was observed within the first two years of follow-up. The probability of evolution to cirrhosis was significantly higher in anti-HDV-positive patients than in patients without antibody to HDV (P less than .001). These findings indicate that HDV infection in patients with chronic hepatitis B is associated with a more-rapid progression to cirrhosis compared with HBsAg carriers with chronic hepatitis and no evidence of HDV infection.     

Cholesterol and chronic hepatitis C virus infection

Cholesterol is an essential molecule for the life cycle of the hepatitis C virus (HCV). This review focuses on the roles of cholesterol in HCV infection and introduces HCV events related to cholesterol metabolism and applications for cholesterol metabolism as a therapeutic target. HCV appears to alter host lipid metabolism into its preferable state, which is clinically recognized as steatosis and hypocholesterolemia. While hepatic fatty acid and triglyceride syntheses are upregulated in chronic hepatitis C patients, no direct evidence of increased hepatic de novo cholesterol biosynthesis has been obtained. Impaired VLDL secretion from hepatocytes is suggested to increase intracellular cholesterol concentrations, which may lead to hypocholesterolemia. Clinically, lower serum cholesterol levels are associated with lower rates of sustained virological responses (SVR) to pegylated‐interferon plus ribavirin therapy, but the reason remains unclear. Clinical trials targeting HMG‐CoA reductase, the rate‐limiting enzyme in the cholesterol biosynthetic pathway, are being conducted using statins. Anti‐HCV actions by statins appear to be caused by the inhibition of geranylgeranyl pyrophosphate synthesis rather than their cholesterol lowering effects. Other compounds that block various steps of cholesterol metabolic pathways have also been studied to develop new strategies for the complete eradication of this virus.     

Immune regulation in chronic hepatitis C virus infection

The immunological result of infection with Hepatitis C virus (HCV) depends on the delicate balance between a vigorous immune response that may clear the infection, but with a risk of unspecific inflammation and, or a less inflammatory response that leads to chronic infection. In general, exhaustion and impairment of cytotoxic function of HCV-specific T cells and NK cells are found in patients with chronic HCV infection. In contrast, an increase in immune regulatory functions is found primarily in form of increased IL-10 production possibly due to increased level and function of anti-inflammatory Tregs. Thus, the major immune players during chronic HCV infection are characterized by a decrease of cytotoxic function and increase of inhibitory functions. This may be an approach to diminish intrahepatic and systemic inflammation. Finally, there has been increasing awareness of regulatory functions of epigenetic changes in chronic HCV infection. A vast amount of studies have revealed the complexity of immune regulation in chronic HCV infection, but the interplay between immune regulation in virus and host remains incompletely understood. This review provides an overview of regulatory functions of HCV-specific T cells, NK cells, Tregs, IL-10, and TGF-β, as well as epigenetic changes in the setting of chronic HCV infection.     

TT virus infection during chronic hepatitis C

OBJECTIVE: The pathogenic role of TT virus (TTV) is not well known, especially during chronic hepatitis C virus (HCV) infection. We retrospectively investigated the presence of TTV DNA in the plasma of patients with chronic HCV infection and compared the characteristics of TTV-DNA-positive and -negative groups. METHODS: Between November 1996 and November 1998, 234 patients were included. Inclusion criteria were persistently elevated serum alanine aminotransferase (ALT) levels, anti-HCV and HCV-RNA positivity, and seronegativity for hepatitis B virus and human immunodeficiency virus markers. TTV DNA was amplified in nested polymerase chain reaction with TTV-specific primers, and products were analyzed by agarose-gel electrophoresis. Data were analyzed using the chi2, Fisher's exact test, or Mann-Whitney test, as appropriate. RESULTS: TTV DNA was detected in 19 (8.1%; 95% confidence interval: 4.6-11.6%) patients. TTV-DNA-positive and TTV-DNA-negative patients did not differ statistically for age, gender ratio, source of HCV infection, HCV disease duration, biological parameters, histological grade, HCV-RNA load, or HCV genotype. Although nonsignificant (p = 0.21), there was a trend for a higher prevalence of TTV DNA in patients with an unknown cause of HCV infection (4/22, 18.2%) than in intravenous drug users (4/84; 4.8%), in those exposed to potential risk factors (4/49; 8.2%), or in those having received blood transfusion (7/79; 8.9%). CONCLUSIONS: Because the rates of HCV replication and the severity of liver lesions in TTV-DNA-negative and -positive patients were similar, the hepatic pathogenicity of TTV in chronic hepatitis C patients is questionable.     

Fibrosis progression in chronic hepatitis C virus infection

Chronic hepatitis C virus infection is typically characterised by slowly progressive hepatic fibrosis. However, it is recognised that some patients do not progress while others rapidly develop significant fibrosis. Here, we review studies that have assessed factors that could influence this rate of fibrotic progression.     

Retreatment of chronic hepatitis C virus infection

Despite advances in antiviral therapy for chronic hepatitis C, approximately half of patients undergoing initial treatment fail to achieve a sustained virologic response (SVR), thus prompting consideration of retreatment with alternative regimens. The decision to re-treat should be based on the severity of liver disease, as well as the presence of clinical and virologic predictors of a successful outcome of additional therapy. Retreatment of patients who were prior nonresponders to interferon monotherapy with interferon plus ribavirin results in SVR rates of 13% to 15%, which can be increased to 25% to 40% if peginterferon plus ribavirin is used. Retreatment of patients who were prior nonresponders to interferon plus ribavirin with peginterferon plus ribavirin unfortunately achieves SVR rates of approximately 10%. The growing number of patients who have been treated and have failed initial therapy highlights the need for the development of more efficacious antiviral agents for the treatment of chronic hepatitis C.     

Sarcoidosis in untreated chronic hepatitis C virus infection

Chronic hepatitis C has been implicated in the pathogenesis of sarcoidosis in several cases of patients treated with interferon-alpha. On the other hand, only in a few cases previously has a possible link between sarcoidosis and untreated chronic hepatitis C virus infection been demonstrated. We report on a patient with chronic hepatitis C who developed cutaneous sarcoidosis without prior interferon-alpha treatment. We hypothesize that viral persistence seen in chronic hepatitis C virus infection might be one of the potential factors that trigger cellular immune response in granulomatous reactions as seen in sarcoidosis, in genetically predisposed patients.     

Sarcoidosis in untreated chronic hepatitis C virus infection

Chronic hepatitis C has been implicated in the pathogenesis of sarcoidosis in several cases of patients treated with interferon‐α. On the other hand, only in a few cases previously has a possible link between sarcoidosis and untreated chronic hepatitis C virus infection been demonstrated. We report on a patient with chronic hepatitis C who developed cutaneous sarcoidosis without prior interferon‐α treatment. We hypothesize that viral persistence seen in chronic hepatitis C virus infection might be one of the potential factors that trigger cellular immune response in granulomatous reactions as seen in sarcoidosis, in genetically predisposed patients.     

Approach to the patient with chronic hepatitis C virus infection

Chronic hepatitis C virus (HCV) infection is common and often asymptomatic. Antibodies against HCV are a highly sensitive marker of infection. Molecular testing for HCV is used to confirm a positive result on antibody testing and to provide prognostic information for treatment; however, quantitative HCV RNA does not correlate with disease severity or risk for progression. Chronic HCV infection is most frequently associated with remote or current intravenous drug use and blood transfusion before 1992, although as many as 20% of infected patients have no identifiable risk factor. In an estimated 15% to 20% of persons infected with HCV, the infection progresses to cirrhosis; alcohol intake is an important cofactor in this progression. Most specialists prefer to include an examination of liver histology in the management of patients with chronic HCV infection to aid prognostic and treatment decisions. The current standard of pharmacologic treatment of chronic HCV is weekly subcutaneous peginterferon in combination with daily oral ribavirin, which results in sustained virologic response in approximately 55% of chronically infected patients. Side effects of interferon therapy include myalgias, fever, nausea, irritability, and depression. The cost-effectiveness of interferon therapy is similar to that of many commonly accepted medical interventions. The primary care physician serves a vital role in identifying patients with chronic HCV infection, educating patients about risk factors for transmission, advising patients about the avoidance of alcohol, and aiding patients in making treatment decisions.     

Importance of age in chronic hepatitis C virus infection

This study was designed to investigate the value of liver biopsy in the management of patients with chronic hepatitis C virus infection and to identify risk factors for fibrosis. It was a prospective audit of clinical, biochemical, virological and radiological features for predicting liver fibrosis in 140 consecutive patients seropositive for antibody against hepatitis C virus. Seventy-five per cent of patients were asymptomatic and 69% had no clinical signs of chronic liver disease. Serum transaminase levels were normal in 44% of patients, less than twice normal in 35% and more than twice normal in 21%. Ultrasound scan was unremarkable in 85%. Sixty-nine per cent of patients were viraemic at the time of liver biopsy. Liver histology revealed that fibrosis was absent in only 10% of patients (stage 0) while cirrhosis was evident in 7% (stage 5). Liver fibrosis was detected in 90% of patients (stage 1, 11%; stage 2, 41%; stage 3, 21%; and stage 4, 10%). Univariate analysis showed that increasing age, clinical signs of chronic liver disease and abnormal ultrasound scan findings were associated with liver fibrosis ( P <0.05); however, multiple linear regression analysis of all the clinical features did not reveal a useful model (sensitivity 42% and specificity 23%) for predicting liver fibrosis. Hence, no combination of clinical, biochemical, virological or radiological data was reliable in discriminating the stage of liver fibrosis in patients with chronic hepatitis C virus infection. However, older patients, especially those with clinical signs of chronic liver disease and abnormal ultrasound scan findings, were more likely to have advanced fibrosis. We recommend liver biopsy as the single most important investigation in detecting liver fibrosis.     

Abnormal uroporphyrin levels in chronic hepatitis C virus infection

A strong association between hepatitis C virus (HCV) infection and porphyria cutanea tarda (PCT) has been observed, but the implications of the viral infection in the metabolism of porphyrins in patients without clinical manifestations of PCT are not known. The levels of porphyrin in plasma and uroporphyrin (URO) and coproporphyrin (COPRO) in 24-hour urine were measured in 156 patients with chronic HCV infection showing no clinical evidence of PCT. Levels of URO higher than the upper limit were observed in 35 of 156 patients (22.4%). The range and the mean values +/- standard deviation were 26-1,196 microg/24 hours and 82 +/- 204 microg/24 hours. Increased levels of COPRO and plasma porphyrin were observed in 12 of 156 patients (7.7%) and 2 of 156 patients (1.3%) respectively. There were no differences between patients with increased URO levels and patients with normal URO levels in terms of gender, age, risk factors for HCV infection, alcohol abuse, or hepatitis B viral infection. Transferrin saturation (p = 0.040), gamma glutamyl transpeptidase (p < 0.0001), aspartate aminotransferase (p = 0.006), and alanine aminotransferase (p = 0.040) were significantly higher in patients with abnormal URO than in patients with normal URO. The frequency of cirrhosis was higher, but not significantly different, in patients with increased URO (16.7%) compared with patients with normal URO (3.8%). The authors demonstrated that even without a clinical manifestation of PCT it is possible to detect abnormalities in the metabolism of porphyrins in patients with chronic HCV infection. The implications of these findings deserve additional investigation.     

Thyroid disorders in chronic hepatitis C virus infection.

The prevalence of thyroid disorders has been evaluated in patients with hepatitis C virus (HCV) infection by many studies. From a review of the published controlled studies, it is possible to observe that: (1) most investigated patients with chronic HCV hepatitis, while a minority evaluated hepatitis C virus antibody (HCVAb)- seropositive patients (the two conditions are not comparable with regards to thyroidal repercussions, in fact, HCVAb-seropositive patients do not necessarily display changes of the immune system present in chronically infected HCV patients); and (2) some authors selected as internal control hepatitis B virus (HBV)-infected patients, while others selected apparently healthy controls or HCVAb-negative subjects. Pooling all data about HCV-positive patients (with chronic hepatitis or HCVAb positivity) and using as control the sum of healthy controls, HBV-infected patients and sera negative for HCVAb, a significant increase of the prevalence has been observed both for thyroid autoimmune disorders (odds ratio [OR] = 1.6; 95% confidence interval = [C]) 1.4-1.9) as well as for hypothyroidism (OR = 2.9; 95% CI = 2.0-4.1). The results of the epidemiologic studies showing an association between HCV infection and thyroid cancer need to be confirmed. The abovementioned evidences seem sufficient to suggest careful thyroid monitoring during the follow-up of patients with HCV infection.     

New therapies for chronic hepatitis C virus infection

Chronic hepatitis C infection is associated with significant morbidity and mortality in addition to substantial social and health-related costs. Since the identification of the virus and determination of the HCV genome over a decade ago, considerable progress has been made in the treatment of chronic hepatitis C infection. However, the current standard combination of interferon-based therapies and ribavirin is effective in only 50% of patients. In addition, this combination is expensive, requires lengthy periods of administration, and is associated with significant side effects. Furthermore, no effective preventive measure, such as vaccination, is currently available. A number of newer therapies, including protease and helicase inhibitors, ribozymes, antisense therapies, and therapeutic vaccines, are in preclinical and clinical development and may significantly enhance existing therapeutic options for the future.