Chronic hepatitis B virus infection. Viral replication and patterns of inflammatory activity: serological, clinical and histological correlations

The Management of Viral Hepatitis in CKD Patients: An Unresolved Problem

Chronic kidney disease (CKD) patients in dialysis (HD) show peculiar, atypical features of clinical presentation and diseases (cardiovascular, metabolic, hematologic). This is also true for viral hepatitis infections, for which CKD patients represent an important risk group. In the past, hepatitis B virus (HBV) was the major cause of viral hepatitis in end-stage renal disease (ESRD). However, the introduction of a rigorous infection-control strategy, routine screening of patients and staff for hepatitis B serologic markers, vaccination of susceptible patients and staff, use of separate rooms and dedicated machines for HD of HbsAg-positive patients have all led to a decline in the spread of HBV infection in dialysis. Despite the prevalence of the antibody-hepatitis C virus (HCV), there has been a marked decrease in HD patients; after the introduction of routine screening for HCV and the use of erythropoietin, its occurrence ranges from 5% to 25% in the United States, with a prevalence of 6.8% in Europe. In CKD and in HD patients, the presence of HBV and HCV is an independent and significant risk factor for death and this risk may be at least partially attributed to chronic liver disease with its attendant complications. Liver disease can progress with modest hepatic inflammation and prominent fibrosis; the natural history of viral hepatitis in these patients is dependent on the immune dysfunction typical of kidney disease. Despite recent advances in antiviral therapy, there are still many uncertainties in regards to the efficacy and long-term outcomes of treatment with antiviral agents.

Dynamics of Genotypic Mutations of the Hepatitis B Virus Associated With Long-Term Entecavir Treatment Determined With Ultradeep Pyrosequencing: A Retrospective Observational Study

The aim of the study is to explore the evolution of genotypic mutations within the reverse transcriptase region in partial virological responders (PVRs) receiving long-term entecavir (ETV) treatment. A total of 32 patients were classified as completely virological responders (CVRs) (n = 12) or PVRs (n = 20). Five partial responders were hepatitis B virus (HBV)-DNA positive after long-term therapy, which lasted for >3 years. A total of 71 serum samples from these 32 patients were assayed by ultra-deep pyrosequencing (UDPS): 32 samples were from all patients at baseline, and 39 were from PVRs with sequential inter-treatment. Approximately 84,708 sequences were generated per sample. At baseline, the quasispecies heterogeneity did not significantly differ between the 2 groups. The frequencies of substitutions indicating pre-existence of nucleos(t)ide analog resistant (NAr) mutants ranged from 0.10% to 6.70%, which did not statistically differ between groups either. However, the substitutions associated with the NAr mutants were significantly different from those associated with the non-NAr mutants in 13 patients; 6 of these patients were PVRs and the others were CVRs. Five patients were HBV DNA positive after regular ETV monotherapy for >3 years, and 4 of these patients underwent mild NAr substitution fluctuations (<20%). One patient developed virological breakthrough while bearing single, double, and triple (rtL180 M, rtM204 V, rtS202G) substitutions. In addition to the common substitutions, unknown amino acid substitutions, such as rtL145 M/S, rtF151Y/L, rtR153Q, rtI224 V, rtN248H, rtS223A, rtS256C, need to be further verified. NAr substitutions are observed at frequencies of 0.10% to 6.7% before therapy. Long-term ETV therapy generally results in virological responses, as long as the proportion of resistance mutations remains at a relatively low level. Genotypic resistance to ETV is detected in all PVRs receiving long-term ETV therapy.

Assessment of current criteria for primary nonresponse in chronic hepatitis B patients receiving entecavir therapy

A primary nonresponse to oral drugs against hepatitis B virus (HBV) is a generally accepted criterion for interrupting treatment. We investigated whether the concept of primary nonresponse suggested by current American (AASLD) and European (EASL) guidelines is appropriate for treatment with entecavir (ETV). The study included 1,254 treatment-naïve patients who had pretreatment HBV DNA levels of >2,000 IU/mL and received ETV 0.5 mg/day for over 6 months. "Primary nonresponse" was defined as a <2 log drop in HBV DNA after 6 months of therapy by AASLD and as a <1 log drop after 3 months by EASL. The cumulative probability of virological response (VR; HBV DNA of <15 IU/mL) was compared in patients with and without primary nonresponse. Median time to achieve VR was significantly shorter in primary responders by AASLD than nonresponders (12 versus 24 months; P = 0.004), but the cumulative probability of achieving a VR at 54 months was similar in the two groups (95.8% versus 100%). Time to achieve a VR and cumulative probability of VR over time did not differ between primary responders and nonresponders by EASL. On-treatment virological breakthrough occurred in 18 patients with a cumulative rate of 5.6% at 72 months. ETV resistance was detected in 13 of these 18 patients (72.2%), who were all classified as primary responder according to both guidelines.

CONCLUSION

Long-term ETV therapy generally leads to a VR in treatment-naïve patients, although the time to achieve it is delayed in primary nonresponders. The current recommendation to change therapy in primary nonresponders needs to be modified to reflect drug differences in antiviral potency and resistance risk.

Hepatitis B virus infection in dialysis patients

Hepatitis B virus (HBV) infection remains a major issue among dialysis patients. It is associated with a high risk of hepatic complication. The liver disease runs a unique clinical course in dialysis patients, as it can progress with modest hepatic inflammation and prominent fibrosis. The conventional cut-off level of serum alanine aminotransferase (ALT) for commencing antiviral therapy may prove too high and inappropriate for dialysis patients, and liver biopsy appears to be the only definitive means to establish the activity of liver disease in dialysis patients. Liver biopsy should be considered in patients with a serum ALT level that is persistently greater than 30 IU/L, or 0.75-fold the upper limit of the normal level, and/or other clinical and laboratory findings that suggest active liver disease. For antiviral treatment, preliminary reports have shown that lamivudine is effective and well tolerated in dialysis patients. However, the long-term efficacy of lamivudine and its optimal effective dose in dialysis patients remain unknown. The prevention of nosocomial transmission among dialysis patients is also important. Universal precaution measures should be strictly observed and the segregation of hepatitis B surface antigen-positive hemodialysis patients should be considered. For HBV non-immune patients, the importance of HBV vaccination should not be overemphasized. Until a new generation of highly immunogenic vaccines that are proven to be safe and effective in patients with end-stage renal disease becomes available, early vaccination before the development of end-stage renal failure remains the best way to secure immunological protection against HBV infection in dialysis patients.

Histopathology and clinical correlates of end-stage hepatitis B cirrhosis: a possible mechanism to explain the response to antiviral therapy

In chronic liver disease associated with histological necroinflammation, clinical severity is frequently greater in those with higher grades of activity. Conventional wisdom assumes that necroinflammation is mild or absent in patients with end-stage hepatitis B virus (HBV) cirrhosis due to the frequent presence of mildly elevated aminotransferase levels, the absence of hepatitis B e antigen (HBeAg), and low or undetectable HBV deoxyribonucleic acid (DNA) levels. However, a histopathologic analysis of such patients has not been undertaken. The aims of this study were 1) to assess severity and histological features of inflammation, 2) to correlate the severity of inflammation with biochemical and virologic parameters, and 3) to define the relationship between inflammation and clinical severity in explanted livers from patients undergoing liver transplantation for HBV cirrhosis. Characteristics of 34 consecutive patients undergoing liver transplantation for HBV cirrhosis were correlated with inflammation and immunohistological findings in the explanted livers. High-grade inflammation (grades 3 and 4) was found in many cases (47.1% interface hepatitis; 14.8% lobular inflammation; and 20.6% portal inflammation). The presence of positive cytoplasmic staining for hepatitis B core antigen (HBcAg) was associated with grade 3 or 4 interface hepatitis (P = .046) and lobular hepatitis (P = .005). There was no correlation between inflammatory activity and age, Asian ethnicity, aminotransferase levels, total bilirubin levels, HBeAg seropositivity, and detectable HBV DNA level. Patients with high-grade inflammation had greater degrees of hepatic decompensation. In conclusion, high-grade inflammation is common in end-stage HBV cirrhosis, but it is not readily detected by biochemical and virologic parameters. High-grade inflammation is associated with a greater degree of hepatic decompensation.

Factors associated or related to with pathological severity of nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has been more and more often regarded as a serious disorder, because nonalcoholic steatohepatitis (NASH), a part of NAFLD, may progress to the end stage of liver disease. Though an advanced age, obesity, diabetes mellitus (DM) etc. being not infrequent conditions in Korea, are known to exacerbate the severity of this disease, there are only a few Korean reports on this subject. The purpose of this study is to identify possible factors that might add up to the pathological severity of this disorder in Korean patients.

METHODS

Of 60 patients with steatosis found at liver biopsy, 43 NAFLD patients were reviewed retrospectively after exclusion of other liver diseases.

RESULTS

The cases of steatosis were mild, moderate, and severe in 9. 10, and 24 patients, respectively. The degree of necroinflammatory activity was mild, moderate, and severe in 33, 9, and 1 patients, respectively. There were no established factors directly related to these classes. As to fibrosis, the cases were classified as none, mild, moderate, severe, and cirrhotic in 9, 11, 16, 7, and 0 patients, respectively. The stage of fibrosis correlated with the age (p < 0.001), BMI (body mass index) (p = 0.032), and the platelet count (p = 0.009), but the presence of NASH was associated only with BMI (p = 0.002) and obesity (p = 0.001).

CONCLUSION

It seems that there are no factors that are directly related to the degree of steatosis or necroinflammatory activity. BMI seems to be a unique factor directly related to both the severity of fibrosis and the presence of NASH. The age and the platelet count are factors that are directly related to the degree of fibrosis but not to the presence of NASH.

A survey of liver pathology in needle biopsies from HBsAg and anti-HBe positive individuals

AIMS

To use laboratory data and liver biopsies, prospectively obtained from hepatitis B surface antigen (HBsAg) and anti hepatitis B e antigen (anti-HBe) positive patients, for the assessment of: (1) the relation between biopsy length/number of portal tracts and sampling error; (2) the relation between the severity of piecemeal necrosis and the new grading terminology (minimal, mild, moderate, and severe chronic hepatitis); and (3) liver pathology, which has not been studied in patients with this specific serological profile.

METHODS

The study group (n = 174) included 104 patients with normal aminotransferase concentrations and no cases with clinically apparent cirrhosis. The specimen length and number of portal tracts were measured at light microscopy examination. Sampling error analysis was related to the discrepancies between aminotransferase concentrations versus histological grade. Detailed histological scorings were undertaken by the reference pathologist and compared with laboratory and hepatitis B virus (HBV) DNA precore sequence data.

RESULTS

Sampling error seemed to be a constant feature, even for biopsies > or = 20 mm, but increased dramatically in biopsies < 5 mm long and/or containing less than four portal tracts. Between 25% and 30% of biopsies, graded as "mild" or "moderate" activity showed features of moderate and severe piecemeal necrosis, respectively. Ten per cent of the patients with normal aminotransferase values had stage III-IV hepatic fibrosis, and 20% had piecemeal necrosis. Only cytoplasmic, not nuclear, core antigen expression was a strong predictor of high hepatitis B viraemia. There was no association between precore stop codon mutations, grade/stage of liver disease, and hepatitis B core antigen (HBcAg) expression.

CONCLUSIONS

The specimen available for light microscopical examination should be > 5 mm long and should contain more than four portal tracts. In addition, the new grading terminology might give the clinician an inappropriately mild impression of the severity of piecemeal necrosis. Furthermore, even in the presence of normal aminotransferase concentrations, considerable liver pathology can be found in 10-20% of HBsAg and anti-HBe positive individuals; such pathology is not associated with the occurrence of precore stop codon mutations.

Relation between laboratory test results and histological hepatitis activity in individuals positive for hepatitis B surface antigen and antibodies to hepatitis B e antigen

BACKGROUND

Hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B e antigen (anti-HBe) commonly coexist, and laboratory tests are often requested to assess histological hepatitis activity. An optimum panel of tests has not been found and the usefulness of hepatitis B virus (HBV) DNA assays in this context has not been established. We assessed various blood tests to find which best predicted hepatitis activity.

METHODS

Routine plasma biochemical liver tests and serum HBV DNA (hybridisation and PCR assays) were assessed prospectively in 123 patients positive for HBsAg and anti-HBe. We scored histological hepatitis activity (hepatitis activity index) and determined whether chronic active hepatitis (chronic hepatitis with portal and periportal lesions) was present. We analysed the relation between laboratory data and the hepatitis activity index or risk of chronic active hepatitis by multiple regression and multiple logistic regression, respectively.

FINDINGS

The analyses provided models for predicting either the hepatitis activity index or the risk of chronic active hepatitis. Aspartate aminotransferase was the most important test in the two models. The contribution of HBV DNA and other assays, especially alanine-aminotransferase activity, were of no practical importance.

INTERPRETATION

Because screening by aspartate-aminotransferase activity could not be improved by the addition of other assays or HBV DNA, patients positive for HBsAg and anti-HBe could be screened for chronic active hepatitis with a single assay and counselling of patients can be improved if proper reference values are used.

Proliferative activity of hepatocytes in chronic viral hepatitis as revealed by immunohistochemistry for proliferating cell nuclear antigen

Liver biopsy specimens of 65 cases of chronic viral hepatitis, including 29 cases of type B, 34 cases of type C, and two cases of non-A, non-B, non-C type, were immunohistochemically stained for proliferating cell nuclear antigen (PCNA) to evaluate the proliferative activity of hepatocytes. According to a histopathologic evaluation using the histology activity index (HAI) scoring system, chronic persistent hepatitis and chronic active hepatitis were clearly differentiated with no overlapping of the score. The labeling indices of PCNA of hepatocytes in chronic persistent hepatitis had a significant relationship with HAI scores (r = .54), suggestive of a contribution of lobular hepatocyte necrosis and/or portal inflammation to the regenerative rate of hepatocytes, but did not exceed 3.0%. On the other hand, 11 of 47 cases of chronic active hepatitis showed PCNA labeling indices higher than 3.5% without any significant relationship with the HAI scores. There was no significant difference, however, of distribution of HAI scores or PCNA labeling indices between hepatitis types B and C. Based on current concepts of the role of hepatocyte proliferation in the development of liver cirrhosis and hepatocellular carcinoma, the present results suggest that the high proliferative rate of hepatocytes subject to the persistent liver cell injury in chronic active hepatitis may be related to a reconstruction pattern of the liver in cases of progression to cirrhosis and development of hepatocellular carcinoma.

Correlation of plasma hepatitis C virus RNA levels with serum alanine aminotransferase in non-A, non-B chronic liver disease

The relationship between plasma hepatitis C virus (HCV) RNA levels, antibody positivity, and hepatocellular damage were studied in 41 patients with non-A, non-B chronic liver disease. The patients were placed into two groups according to the plasma levels of HCV-RNA: plasma HCV-RNA level was estimated as high when detected by a one stage polymerase chain reaction (PCR) and as low when detectable only after a two stage PCR. Anti-HCV (first and second generation assays) and anti-GOR were also measured. The mean alanine aminotransferase (ALT) level of the high HCV-RNA group was 115 +/- 62 IU/l, whereas that of the low HCV-RNA group was 59 +/- 37 IU/l (P < 0.05). Patients with ALT levels above 100 IU/l had invariably a high level of HCV-RNA. There were no differences in clinical features in relation to the presence of anti-GOR or anti-HCV. Circulating HCV-RNA levels but not anti-HCV or anti-GOR antibodies correlated with hepatocellular damage.

Beta-2 microglobulin as a marker of HIV disease status in Nairobi, Kenya

Serum beta-2 microglobulin (beta 2-M) has prognostic value similar to lymphocyte profiles for predicting disease progression in those infected with the human immunodeficiency virus (HIV). However, the relationship between beta 2-M and HIV disease progression among inhabitants of countries with endemic tropical diseases has not been evaluated. To determine the relationship between serum beta 2-M levels and HIV infection and disease status in an African population, serum beta 2-M levels were measured in 369 patients attending a sexually transmitted disease (STD) clinic in Nairobi, Kenya. Mean serum beta 2-M was significantly higher in HIV seropositive than in HIV seronegative individuals. Among HIV infected patients, higher mean beta 2-M levels were observed in those with HIV associated symptoms or laboratory markers of advanced HIV disease. Significant inverse correlations between beta 2-M and the percentage of CD4 lymphocytes or CD4/CD8 ratio were found. These findings suggest that beta 2-M measurements may have prognostic value for HIV infected populations in developing countries.

Activation of class I major histocompatibility complex gene expression by hepatitis B virus

Normal hepatocytes express very few class I major histocompatibility complex (MHC I) molecules, but MHC I expression is elevated in hepatitis B virus (HBV) infection. We report here that hepatoblastoma cells with replicating HBV genomes express three- to fourfold-higher levels of MHC I protein and mRNA than do parent cells without HBV DNA. Transient transfection assays demonstrated that the HBV X protein trans activated transcription from an MHC I promoter and allowed identification of cis elements important for trans activation.

Hepatitis B-DNA replication and histological patterns in liver biopsy specimens of chronic HBsAg positive patients with and without hepatitis delta virus superinfection

The role of active hepatitis B virus (HBV) infection in chronic HBsAg positive hepatitis with and without hepatitis delta virus (HDV) superinfection was analysed in percutaneous liver biopsy specimens from 50 patients. Each specimen was divided into two--one part for histological evaluation and for the detection of HBcAg and delta antigen; the other part was tested for HBV-DNA using Southern blotting. Ten cases were of chronic lobular hepatitis, 10 of chronic persistent hepatitis, and 30 of chronic active hepatitis. Ten cases were delta antigen positive and showed high grade lobular activity but no evidence of HBV-DNA episomal forms or HBcAg reactivity. Twenty one cases showed HBV-DNA replicative intermediate forms; 19 had high grade lobular activity, which occurred in five cases without evidence of free viral DNA. Of the 21 biopsy specimens with HBV-DNA episomal forms, 14 were positive for HBcAg; only one of the 19 cases without detectable viral DNA was positive for such antigen. These data indicate that the presence of HBV or HDV active infection correlates with the histological finding of prominent lobular necrosis. Moreover, intrahepatic HBV-DNA seems to be a more sensitive marker than the presence of viral antigens for indicating HBV replication.

Change of hepatitis B virus DNA distribution associated with the progression of chronic hepatitis

Hepatitis B virus (HBV) DNA was detected by in situ hybridization in 53 out of 74 liver specimens from patients with chronic HBV infection. The distribution of HBV DNA was classified into three patterns: diffuse (HBV DNA distributed diffusely, within the section of specimen), lobular (HBV DNA was present in 1/3-2/3 of the section) and spotty. All three specimens from asymptomatic HBV carriers showed the diffuse pattern. In the advanced stage of liver disease (chronic active hepatitis with severe activity and liver cirrhosis), a decreased number of specimens showed the diffuse pattern, whereas the number of specimens with the lobular pattern increased. From these data, we conclude that HBV may replicate diffusely in the liver in the early stage of chronic liver disease, and the site of HBV replication becomes localized in the advanced stage of the disease. The main target cells of immunocytes may be hepatocytes undergoing HBV replication, because HVB DNA was frequently detected in areas of focal, piecemeal and bridging hepatic necrosis.

Changes of serum HBV-DNA in relation to serum transaminase level during acute exacerbation in patients with chronic type B hepatitis

To examine the relationship between changes of serum hepatitis B virus-dexoyribonucleic acid (HBV-DNA) and transaminase levels during acute exacerbation of chronic type B hepatitis, serial serum specimens from 74 patients were assayed for HBV-DNA by slot blot hybridization with 32P-labeled cloned HBV-DNA as probe. Of these patients, serial serum specimens were obtained with an interval of 2-7 days in 22 patients (Group I), 8-14 days in 30 patients (Group II) and 15-30 days in 22 patients (Group III). The peak of serum HBV-DNA was reached shortly before or simultaneously with the maximum elevation of serum alanine transaminase (ALT) in most (greater than 90%) of the acute exacerbations. In contrast, the peak of serum ALT was reached before maximum elevation of serum HBV-DNA in only 13.6% of Group I, 3.3% of Group II and 13.6% of Group III (9.5% of whole series). The results suggest that the increase of serum HBV-DNA is an event preceding, rather than the result of, hepatocytolysis in most of the acute exacerbations occurring in patients with chronic type B hepatitis.