Synergism of chronic alcoholism and hepatitis B infection in liver disease

Occult hepatitis B virus and hepatocellular carcinoma

Occult hepatitis B virus (HBV) infection (OBI) is a challenging pathobiological and clinical issue that has been widely debated for several decades. By definition, OBI is characterized by the persistence of HBV DNA in the liver tissue (and in some cases also in the serum) in the absence of circulating HBV surface antigen (HBsAg). Many epidemiological and molecular studies have indicated that OBI is an important risk factor for hepatocellular carcinoma (HCC) development. OBI may exert direct pro-oncogenic effects through the activation of the same oncogenic mechanisms that are activated in the course of an HBsAg-positive infection. Indeed, in OBI as in HBV-positive infection, HBV DNA can persist in the hepatocytes both integrated into the host genome as well as free episome, and may maintain the capacity to produce proteins-mainly X protein and truncated preS-S protein - provided with potential transforming properties. Furthermore, OBI may indirectly favor HCC development. It has been shown that the persistence of very low viral replicative activity during OBI may induce mild liver necro-inflammation continuing for life, and substantial clinical evidence indicates that OBI can accelerate the progression of liver disease towards cirrhosis that is considered the most important risk factor for HCC development.

Occult hepatitis B infection and HBV replicative activity in patients with cryptogenic cause of hepatocellular carcinoma

We aimed to investigate the incidence of occult hepatitis B infection (OBI) in patients with "cryptogenic" hepatocellular carcinoma (HCC) and to study the HBV replicative activity in these patients. Tumorous and adjacent nontumorous liver tissues were obtained from 33 cryptogenic HCC patients and 28 HCC patients with identifiable causes (13 with chronic hepatitis B [CHB], six with chronic hepatitis C, and nine alcohol-related). OBI was identified by nested polymerase chain reaction (PCR). Intrahepatic HBV DNA, covalently closed circular DNA (cccDNA), and pregenomic RNA (pgRNA) were quantified by real-time PCR and reverse-transcription PCR (RT-PCR), respectively. OBI was identified in 24 (73%) cryptogenic HCC patients, one (17%) HCC patient with HCV, and five (56%) patients with alcohol-related HCC. In HCC patients with OBI, HBV DNA were detected in ≥2 HBV genomic regions more often in nontumorous tissues than in tumorous tissues (90% versus 57%, respectively; P = 0.007). Cryptogenic HCC patients with OBI had lower intrahepatic total HBV DNA levels than HCC patients with CHB (median: 0.010 versus 3.19 copies/cell, respectively; P < 0.0001). Only six (26%) cryptogenic HCC patients with OBI had detectable cccDNA (median: <0.0002 copies/cell), which was significantly lower than that of the CHB patients (median: 0.005 copies/cell; P < 0.0001). HBV pgRNA were detectable in 12 (52%) cryptogenic HCC patients with OBI (median: 0.0001 copies/cell), which was significantly lower than that of the CHB patients (median: 2.90 copies/cell; P < 0.001).

CONCLUSION

73% of patients with apparently unidentifiable causes for HCC were HBV-related. The detection rate was higher in nontumorous tissues than tumorous tissues. The low intrahepatic HBV DNA and pgRNA levels indicated that persistent viral replication and possibly HBV integration are the likely causes of HCC in OBI patients.

Selecting appropriate management strategies for chronic hepatitis B: who to treat

BACKGROUND

Hepatitis B virus (HBV) infection is a significant problem. In the United States estimates indicate that 0.3% of the population (1.25 million individuals) have chronic hepatitis B infection.

METHODS

Review of published practice guidelines and literature on management of hepatitis B to determine: 1) Which persons in Western populations are at the highest risk for HBV infection and should be screened for HBV seromarkers to identify those who are chronically infected and those who need to be protected with hepatitis B vaccine; 2) The importance of regular monitoring in persons with chronic hepatitis B, the frequency of monitoring, and which tests should be performed; 3) How to identify the patients who are appropriate candidates for antiviral therapy.

RESULTS

Recommendations for screening, diagnosis, monitoring, and treatment of chronic HBV infection are reviewed. Important differences are discussed between the Practice Guidelines for chronic hepatitis B developed by the American Association for the Study of Liver Diseases (AASLD), the European Association for the Study of the Liver (EASL), and the Asian Pacific Association for the Study of the Liver (APASL). In addition, this article reviews which patients who are no covered by these Guidelines might be candidates for antiviral therapy.

DISCUSSION

Established practice guidelines provide direction to providers for the diagnosis and management of chronic HBV infection to reduce the risk of serious sequelae. However, not all patients with chronic hepatitis B are identified, and many of those who are diagnosed do not receive adequate management and follow-up.

Natural history of chronic hepatitis B and C

Hepatitis B virus (HBV) affects more than 300 million individuals worldwide and in the United States approximately 1.25 million individuals are chronic carriers of HBV. The risk of becoming a chronic hepatitis B virus surface antigen carrier is dependent upon the mode of acquisition of infection as well as the age of the individual at the time of infection. For those individuals with high levels of viral replication, chronic active hepatitis with progression to cirrhosis, liver failure and hepatocellular carcinoma (HCC) is common and liver transplantation is an excellent treatment option for patients with end-stage liver disease from HBV. Patients with chronic HBV infection should be screened periodically for hepatoma, although screening strategies have not been proven to prolong survival. Newer antiviral agents for the treatment of HBV are potent inhibitors of HBV-DNA and their long-term effect on the natural history of HBV is yet to be proven. The natural history of hepatitis C virus (HCV) infection is less well defined than that of chronic HBV. Certain patients who are chronic carriers of HCV may never develop extensive fibrosis, whereas others will progress to chronic active hepatitis with cirrhosis, HCC and end-stage liver disease. Factors that influence the progression of HCV are those related to the host, including the age at acquisition of infection, gender and immune status, and the disease process is accelerated in patients who consume regular amounts of alcohol. Hepatocellular carcinoma develops frequently in patients with HCV infection and its overall incidence is increasing due to this chronic viral disease. Patients with HCV cirrhosis should be screened regularly for hepatoma and liver transplantation is an effective treatment option for those with end-stage disease. The impact of antiviral therapy on the natural history of HCV is still to be determined and should be the focus of large clinical trials.

Exploring the combined action of lifetime alcohol intake and chronic hepatotropic virus infections on the risk of symptomatic liver cirrhosis. Collaborative Groups for the Study of Liver Diseases in Italy

Although alcohol intake and hepatitis B and C virus (HBV and HCV) infections are the major determinants of liver cirrhosis (LC) in western countries, the joint effect of these factors on LC risk has not yet been adequately studied. Data from three case-control studies performed in Italy were used. Cases were 462 cirrhotic patients admitted to Hospitals for liver decompensation. Controls were 651 inpatients admitted for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). Three approaches were used to explore the interaction structure. The Breslow and Storer parametric family of relative risk functions showed that an intermediate structure of interaction from additive to multiplicative was the most adequate one. The Rothman synergism index showed that the interaction structure between LDAI and viral status differed significantly from the additive model in particular for high levels of alcohol intake. When multiple regression additive and multiplicative models were compared after adjustment for the known confounding variables. a trend of the interaction structure towards the multiplicative model was observed at increasing levels of consumption. Better methods are needed for assessing mixed interaction structures in conditions characterized by multifactorial etiologies like cirrhosis of the liver.

Independent and combined action of hepatitis C virus infection and alcohol consumption on the risk of symptomatic liver cirrhosis

Although alcohol intake and hepatitis C virus (HCV) infection are the major determinants of liver cirrhosis (LC) in Western countries, the joint effect of these two factors on LC risk has not yet been adequately studied. We used data from two hospital-based case-control studies performed in Italy. Cases were 285 cirrhotic patients admitted for the first time to district hospitals for liver decompensation. Controls were 417 patients admitted during the same period, and in the same hospitals as the cases, for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). Serum HCV antibodies (anti-HCV) were detected using a second-generation test and recombinant immunoblotting assay. We found a dose-effect relationship between LDAI and the risk of LC in both anti-HCV-negative and -positive subjects. Considering the extreme LDAI categories (LDAI = 0 g, lifetime teetotalers, and LDAI = 175 g), the LC odds ratios increased from 1.0 (reference category) to 15.0 (95% CI, 7.1-31.7) and from 9.2 (95% CI, 2.0-43.2) to 147.2 (95% CI, 42.1-514.3) in anti-HCV-negative and -positive patients respectively. The interaction between LDAI and HCV showed an additive structure for LDAI < 50 g/day and a multiplicative structure for consumption > 125 g/day. Alcohol intake and HCV infection are independent risk factors for symptomatic liver cirrhosis, each being sufficient to induce the disease. In subjects with high alcohol intake, the coexistence of HCV infection multiplies the alcohol-associated risk of cirrhosis. In subjects with low alcohol intake, other factors could be involved.

Is alcohol a risk factor for liver cirrhosis in HBsAg and anti-HCV negative subjects? Collaborative Groups for the Study of Liver Diseases in Italy

BACKGROUND/AIMS

In order to evaluate the association between alcohol intake and the risk of liver cirrhosis in the absence of B and C hepatitis viruses, we analyzed data from three hospital-based case-control studies performed in various Italian areas.

METHODS

From the case and control series we excluded HBsAg and/or anti-HCV positive patients. Cases were 221 cirrhotic patients admitted for the first time to hospital for liver decompensation. Controls were 614 patients admitted to the same hospitals during the same period as the cases for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI).

RESULTS

We found a dose-effect relationship between LDAI and the risk of liver cirrhosis (LC). Considering the extreme LDAI categories (LDAI = 0 g: lifetime teetotallers and LDAI > or = 100 g), the LC odds ratio (OR) increased from 1.0 (reference category) to 44.7 (95% confidence interval: 95% CI: 20.0-99.9). An increased risk of LC associated with the female gender independent of alcohol consumption was also observed (OR = 2.9; 95% CI: 1.8-4.6).

CONCLUSIONS

Alcohol intake acts as a risk factor for symptomatic liver cirrhosis also in the absence of HBV and/or HCV infection. Besides alcohol and viruses, some unknown gender-related factors might be involved in the occurrence of the disease.

The effect of drinking coffee and smoking cigarettes on the risk of cirrhosis associated with alcohol consumption. A case-control study. Provincial Group for the Study of Chronic Liver Disease

In order to assess the interaction between alcohol intake, tobacco smoking and coffee consumption in determining the risk of liver cirrhosis we carried out a hospital-based case-control study involving 115 patients at their first diagnosis of cirrhosis and 167 control patients consecutively enrolled in the General Hospitals of the Province of L'Aquila (Central Italy). The mean life-time daily alcohol intake (as g ethanol consumed daily) was measured by direct patient interviews, whose reproducibility was > 0.80 and similar for cases and controls, as checked by interviewing the relatives of a sample of 50 cases and 73 controls. During the same patient's interview we also measured the mean consumption of coffee (daily number of cups of filtered coffee) and tobacco (life-time daily number of cigarettes smoked). A dose-effect relationship on the risk of cirrhosis was present both for alcohol intake--for which the risk was significantly increased above 100 g of daily intake--and for cigarette consumption. The latter did not however improve the goodness-of-fit of a logistic regression model including alcohol intake as covariate. By contrast, coffee consumption had a protective effect on the risk of cirrhosis and significantly improved the goodness-of-fit of such a model. Abstaining from coffee consumption determined both a significantly increased risk of cirrhosis, even for daily alcohol intake below 100 g, and a multiplicative effect with alcohol intake on this risk. In patients drinking > or = 101 g ethanol daily the relative risk increased from 5.5 (95% confidence interval: 1.4-22.0) for coffee consumers to 10.8 (95% confidence interval: 1.3-58.1) for coffee abstainers.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiology of alcoholic liver disease

Although mortality from alcoholic liver disease has declined in some Western countries in recent years, elsewhere it is increasing and overall it remains a major health problem. Deaths are predominantly seen in patients with alcoholic hepatitis or cirrhosis, and when they occur in patients with fatty liver are usually unrelated to liver disease. Progression to cirrhosis is correlated with the severity of fatty liver and particularly with the presence of alcoholic hepatitis. Mortality from cirrhosis is strongly correlated with per capita alcohol consumption. The decline in cirrhosis mortality rates seen recently is related in part to decreases in per capita consumption, but probably also to the growth of self-help organizations which facilitate abstinence from alcohol. Recent studies suggest there is not an invariable dose-response relationship between alcohol intake and the severity of liver disease and that alcohol has a permissive effect which allows other aetiological factors to operate. Factors that influence susceptibility to alcoholic liver disease include gender (women develop alcoholic cirrhosis more readily than men), concomitant hepatitis C infection and possibly hepatitis B infection. It is uncertain whether HLA status or immune mechanisms are implicated. The systematic use of screening tests for hazardous consumption combined with early intervention therapies offers a good prospect of reducing morbidity and mortality from alcoholic liver disease.

Investigation of alcoholic liver disease

In heavy drinkers with clinical evidence of liver disease, routine investigations should exclude the possibility of other chronic liver diseases of non-alcoholic aetiology requiring specific therapy--these include chronic viral hepatitis, autoimmune diseases of the liver, Wilson's disease and genetic haemochromatosis. If abnormalities in liver biochemistry persist despite abstinence, or if the diagnosis of alcoholic liver disease is in doubt, a liver biopsy should be carried out. Studies evaluating the role of liver biopsy in alcoholic liver disease suggest that without histological confirmation the diagnosis will be inaccurate in 10-20% of patients. Serum biochemistry and the currently available imaging modalities have severe limitations in determining the relative contributions of fatty liver, alcoholic hepatitis and cirrhosis to the overall picture in alcoholic liver disease. Histological examination is therefore of additional value in determining the prognosis, which is worst in patients with a combination of alcoholic hepatitis and cirrhosis. There are a number of indices available, based on clinical and laboratory information, for evaluating the short-term prognosis, but these can only be used with accuracy if the histological pattern of damage has initially been evaluated.