Liver histology in patients with HBsAg negative anti-HBc and anti-HCV positive chronic hepatitis

Epidemiological and clinical aspects of hepatitis B virus infection in Italy over the last 50 years

A relevant gradual reduction of both the incidence rate of acute hepatitis B (AHB) and prevalence of chronic hepatitis B has occurred in Italy in the last 50 years, due to substantial epidemiological changes: Improvement in socioeconomic and hygienic conditions, reduction of the family unit, accurate screening of blood donations, abolition of re-usable glass syringes, hepatitis B virus (HBV)-universal vaccination started in 1991, use of effective well tolerated nucleo(t)side analogues able to suppress HBV replication available from 1998, and educational mediatic campaigns against human immunodeficiency virus infection focusing on the prevention of sexual and parenteral transmission of infections. As an example, AHB incidence has gradually decreased from 10/100000 inhabitants in 1985 to 0.21 in 2020. Unfortunately, the coronavirus disease 2019 (COVID-19) pandemic has interrupted the trend towards HBV eradication. In fact, several HBV chronic carriers living in the countryside have become unable to access healthcare facilities for screening, diagnosis, clinical management, and nucleo(t)side analogue therapy in the COVID-19 pandemic, mainly for anxiety of becoming infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), movement restrictions, and reduced gains from job loss. In addition, one-third of healthcare facilities and personnel for HBV patients have been devolved to the COVID-19 assistance.

Prediction of occult hepatitis B virus infection in liver transplant donors through hepatitis B virus blood markers

BACKGROUND

Occult hepatitis B virus infection is defined as detectable HBV-DNA in liver of HBsAg-negative individuals, with or without detectable serum HBV-DNA. In deceased liver donors, results of tissue analysis cannot be obtained prior to allocation for liver transplantation.

AIMS

we investigated prevalence and predictability of occult hepatitis B using blood markers of viral exposure/infection in deceased liver donors.

METHODS

In 50 consecutive HBsAg-negative/anti-HBc-positive and 20 age-matched HBsAg-negative/anti-HBc-negative donors, a nested-PCR assay was employed in liver biopsies for diagnosis of occult hepatitis B according to Taormina criteria. All donors were characterized for plasma HBV-DNA and serum anti-HBs/anti-HBe.

RESULTS

In liver tissue, occult hepatitis B was present in 30/50 anti-HBc-positive (60%) and in 0/20 anti-HBc-negative donors (p<0.0001). All anti-HBc-positive donors with detectable HBV-DNA in plasma (n=5) or anti-HBs>1,000 mIU/mL (n=5) eventually showed occult infection, i.e, 10/30 occult hepatitis B-positive donors which could have been identified prior to transplantation. In the remaining 40 anti-HBc-positive donors, probability of occult infection was 62% for anti-HBe-positive and/or anti-HBs ≥ 58 mIU/mL; 29% for anti-HBe-negative and anti-HBs<58 mIU/mL.

CONCLUSIONS

In deceased donors, combining anti-HBc with other blood markers of hepatitis B exposure/infection allows to predict occult hepatitis B with certainty and speed in one third of cases. These findings might help refine the allocation of livers from anti-HBc-positive donors.

Epidemiology of acute and chronic hepatitis B and delta over the last 5 decades in Italy

The spread of hepatitis B virus (HBV) infection has gradually decreased in Italy in the last 5 decades as shown by the steady reduction in the incidence rates of acute hepatitis B, from 10/100000 inhabitants in 1984 to 0.85/100000 in 2012, and by the reduced prevalence of hepatitis B surface antigen (HBsAg)-positive cases among chronic hepatitis patients with different etiologies, from 60% in 1975 to about 10% in 2001. The prevalence of HBsAg chronic carriers in the general population also decreased from nearly 3% in the 1980s to 1% in 2010. Linked to HBV by its characteristics of defective virus, the hepatitis delta virus (HDV) has shown a similar epidemiological impact on the Italian population over time. The incidence of acute HDV infection decreased from 3.2/100000 inhabitants in 1987 to 0.8/100000 in 2010 and the prevalence of HDV infection in HBsAg chronic carriers decreased from 24% in 1990 to 8.5% in 2006. Before the beneficial effects of HBV mass vaccination introduced in 1991, the decreased endemicity of HBV and HDV infection in Italy paralleled the improvement in screening blood donations, the higher standard of living and impressive reduction in the birth rate associated with a marked reduction in the family size. A further contribution to the decline in HBV and HDV infections most probably came from the media campaigns to prevent the spread of human immunodeficiency virus infection by focusing the attention of the general population on the same routes of transmission of viral infections such as unsafe sexual intercourse and parenteral exposures of different kinds.

Clinical impact of occult hepatitis B virus infection in immunosuppressed patients

Occult hepatitis B infection (OBI), is characterized by low level hepatitis B virus (HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepatitis B surface antigen (HBsAg)-/anti-HBs-negative subjects is considered indicative of OBI. OBI is mostly observed in the window period of acute HBV infection in blood donors and in recipients of blood and blood products, in hepatitis C virus chronic carriers, in patients under pharmacological immunosuppression, and in those with immunodepression due to HIV infection or cancer. Reactivation of OBI mostly occurs in anti-HIV-positive subjects, in patients treated with immunosuppressive therapy in onco-hematological settings, in patients who undergo hematopoietic stem cell transplantation, in those treated with anti-CD20 or anti-CD52 monoclonal antibody, or anti-tumor necrosis factors antibody for rheumatological diseases, or chemotherapy for solid tumors. Under these conditions the mortality rate for hepatic failure or progression of the underlying disease due to discontinuation of specific treatment can reach 20%. For patients with OBI, prophylaxis with nucleot(s)ide analogues should be based on the HBV serological markers, the underlying diseases and the type of immunosuppressive treatment. Lamivudine prophylaxis is indicated in hemopoietic stem cell transplantation and in onco-hematological diseases when high dose corticosteroids and rituximab are used; monitoring may be indicated when rituximab-sparing schedules are used, but early treatment should be applied as soon as HBsAg becomes detectable. This review article presents an up-to-date evaluation of the current knowledge on OBI.

Clinical impact of occult hepatitis B virus infection in immunosuppressed patients

Occult hepatitis B infection (OBI), is characterized by low level hepatitis B virus (HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepatitis B surface antigen (HBsAg)-/anti-HBs-negative subjects is considered indicative of OBI. OBI is mostly observed in the window period of acute HBV infection in blood donors and in recipients of blood and blood products, in hepatitis C virus chronic carriers, in patients under pharmacological immunosuppression, and in those with immunodepression due to HIV infection or cancer. Reactivation of OBI mostly occurs in anti-HIV-positive subjects, in patients treated with immunosuppressive therapy in onco-hematological settings, in patients who undergo hematopoietic stem cell transplantation, in those treated with anti-CD20 or anti-CD52 monoclonal antibody, or anti-tumor necrosis factors antibody for rheumatological diseases, or chemotherapy for solid tumors. Under these conditions the mortality rate for hepatic failure or progression of the underlying disease due to discontinuation of specific treatment can reach 20%. For patients with OBI, prophylaxis with nucleot(s)ide analogues should be based on the HBV serological markers, the underlying diseases and the type of immunosuppressive treatment. Lamivudine prophylaxis is indicated in hemopoietic stem cell transplantation and in onco-hematological diseases when high dose corticosteroids and rituximab are used; monitoring may be indicated when rituximab-sparing schedules are used, but early treatment should be applied as soon as HBsAg becomes detectable. This review article presents an up-to-date evaluation of the current knowledge on OBI.

Hepatitis B-core antibody positive donors in liver transplantation and their impact on graft survival: evidence from the Liver Match cohort study

BACKGROUND & AIMS

The appropriate allocation of grafts from HBcAb positive donors in liver transplantation is crucial, yet a consensus is still lacking.

METHODS

We evaluated this issue within Liver Match, a prospective observational Italian study. Data from 1437 consecutive, first transplants performed in 2007-2009 using grafts from deceased heart beating donors were analyzed (median follow-up: 1040 days). Of these, 219 (15.2%) were HBcAb positive. Sixty-six HBcAb positive grafts were allocated to HBsAg positive and 153 to HBsAg negative recipients.

RESULTS

329 graft losses occurred (22.9%): 66 (30.1%) among 219 recipients of HBcAb positive grafts, and 263 (21.6%) among 1218 recipients of HBcAb negative grafts. Graft survival was lower in recipients of HBcAb positive compared to HBcAb negative donors, with unadjusted 3-year graft survival of 0.69 (s.e. 0.032) and 0.77 (0.013), respectively (log-rank, p=0.0047). After stratifying for recipient HBsAg status, this difference was only observed among HBsAg negative recipients (log rank, p=0.0007), 3-year graft survival being excellent (0.88, s.e. 0.020) among HBsAg positive recipients, regardless of the HBcAb donor status (log rank, p=0.4478). Graft loss due to de novo HBV hepatitis occurred only in one patient. At Cox regression, hazard ratios for graft loss were: MELD (1.30 per 10 units, p=0.0002), donor HBcAb positivity (1.56, p=0.0015), recipient HBsAg positivity (0.43, p <0.0001), portal vein thrombosis (1.99, p=0.0156), and DRI (1.41 per unit, p=0.0325).

CONCLUSIONS

HBcAb positive donor grafts have better outcomes when transplanted into HBsAg positive than HBsAg negative recipients. These findings suggest that donor HBcAb positivity requires more stringent allocation strategies.

Massive APOBEC3 editing of hepatitis B viral DNA in cirrhosis

DNA viruses, retroviruses and hepadnaviruses, such as hepatitis B virus (HBV), are vulnerable to genetic editing of single stranded DNA by host cell APOBEC3 (A3) cytidine deaminases. At least three A3 genes are up regulated by interferon-α in human hepatocytes while ectopic expression of activation induced deaminase (AICDA), an A3 paralog, has been noted in a variety of chronic inflammatory syndromes including hepatitis C virus infection. Yet virtually all studies of HBV editing have confined themselves to analyses of virions from culture supernatants or serum where the frequency of edited genomes is generally low (≤10⁻²). We decided to look at the nature and frequency of HBV editing in cirrhotic samples taken during removal of a primary hepatocellular carcinoma. Forty-one cirrhotic tissue samples (10 alcoholic, 10 HBV⁺, 11 HBV⁺HCV⁺ and 10 HCV⁺) as well as 4 normal livers were studied. Compared to normal liver, 5/7 APOBEC3 genes were significantly up regulated in the order: HCV±HBV>HBV>alcoholic cirrhosis. A3C and A3D were up regulated for all groups while the interferon inducible A3G was over expressed in virus associated cirrhosis, as was AICDA in ∼50% of these HBV/HCV samples. While AICDA can indeed edit HBV DNA ex vivo, A3G is the dominant deaminase in vivo with up to 35% of HBV genomes being edited. Despite these highly deleterious mutant spectra, a small fraction of genomes survive and contribute to loss of HBeAg antigenemia and possibly HBsAg immune escape. In conclusion, the cytokine storm associated with chronic inflammatory responses to HBV and HCV clearly up regulates a number of A3 genes with A3G clearly being a major restriction factor for HBV. Although the mutant spectrum resulting from A3 editing is highly deleterious, a very small part, notably the lightly edited genomes, might help the virus evolve and even escape immune responses.

Retroviruses and hepadnaviruses such as hepatitis B virus (HBV) are vulnerable to mutation by host cell single stranded DNA cytidine deaminases. The result is hypermutated viral peppered with uracil residues. While there are potentially 11 such human enzymes, the major players belong to the 7 gene APOBEC3 cluster on chromosome 22, some of which can be activated by anti-viral interferons. We investigated the nature and frequency of HBV editing in 41 cirrhotic samples following surgical removal of primary hepatocellular carcinoma. Numerous APOBEC3 genes were activated in the decreasing order HCV±HBV>HBV>alcoholic cirrhosis. We observed that APOBEC3G was the dominant restricting factor in vivo with up to 35% of HBV edited genomes. Among the HBV mutants generated by APOBEC3 editing, we found a small fraction of lightly APOBEC3G edited genomes that can impact HBV replication in vivo and possibly immune escape.

Hepatitis C virus core protein subverts the antiviral activities of human Kupffer cells

BACKGROUND & AIMS

Kupffer cells (KC) are important innate immune cells of the liver, functioning as scavenging sinusoidal phagocytes and transducers of pattern recognition signals, including those of toll-like receptors (TLRs). The hepatitis C virus core protein (HCVc) engages TLR2 on peripheral blood monocytes and induces production of multiple inflammatory cytokines. We examined the effects of HCVc on human primary KC functions.

METHODS

KC were isolated from living donor allografts and stimulated with HCVc and/or ligands for TLRs. KC were examined for production of cytokines, expression of programmed death-ligand 1 (PD-L1), secretion of type 1 interferons (IFNs), and expression of the apoptosis-inducing protein tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL).

RESULTS

HCVc acts as a ligand for TLR2 on human KC, inducing them to secrete interleukin (IL)-1beta, TNF-alpha, and IL-10 and up-regulate cell surface PD-L1. HCVc blocked TLR3-mediated secretion of IFN-alpha, IFN-beta, and cell surface expression of the cytotoxic molecule TRAIL. Inhibition of phosphoinositide 3 kinase with LY294002 blocked the up-regulation of PD-L1 by TLR ligands and the TLR3-specific induction of TRAIL and type 1 IFNs.

CONCLUSIONS

KC are intravascular macrophages that are continuously exposed to, and tolerant of, bacterial TLR ligands, which are delivered via the portal circulation. By mimicking a bacterial TLR2 ligand and effectively blocking the TLR3-mediated, double-stranded RNA-induced antiviral response, HCVc might appear to exploit this unique aspect of immunity in the liver.

Clinical and virological improvement of hepatitis B virus-related or hepatitis C virus-related chronic hepatitis with concomitant hepatitis A virus infection

BACKGROUND

We evaluated the clinical and virological characteristics of hepatitis A virus infection in persons concomitantly infected with hepatitis B virus (HBV) or hepatitis C virus (HCV).

METHODS

We enrolled 21 patients with acute hepatitis A and chronic hepatitis with no sign of liver cirrhosis, 13 patients who were positive for hepatitis B surface antigen (case B group), 8 patients who were anti-HCV positive (case C group), and 21 patients with acute hepatitis A without a preexisting liver disease (control A group). Two control groups of patients with chronic hepatitis B (control B group) or C (control C group) were also chosen. All control groups were pair-matched by age and sex with the corresponding case group.

RESULTS

Fulminant hepatitis A was never observed, and hepatitis A had a severe course in 1 patient in the case B group and in 1 patient in the control A group. Both patients recovered. On admission, HBV DNA was detected in 1 patient in the case B group (7.7%) and in 13 patients (50%) in the control B group; HCV RNA was found in no patient in the case C group and in 16 patients (81.2%) in the control C group. Of 9 patients in the case B group who were followed up for 6 months, 3 became negative for hepatitis B surface antigen and positive for hepatitis B surface antibody, 2 remained positive for hepatitis B surface antigen and negative for HBV DNA, and 4 became positive for HBV DNA with a low viral load [corrected] Of 6 patients in the case C group who were followed up for 6 months, 3 remained negative for HCV RNA, and 3 had persistently low viral loads.

CONCLUSION

Concomitant hepatitis A was always self-limited, associated with a marked inhibition of HBV and HCV genomes, and possibly had a good prognosis for the underlying chronic hepatitis.

Ductular proliferation in liver tissues with severe chronic hepatitis B: An immunohistochemical study

AIM: To clarify the pathogenesis of ductular proliferation and its possible association with oval cell activation and hepatocyte regeneration.

METHODS: Immunohistochemical staining and image analysis of the ductular structures in the liver tissues from 11 patients with severe chronic hepatitis B and 2 healthy individuals were performed. The liver specimens were sectioned serially, and then cytokeratin 8 (CK8), CK19, OV6, proliferating cell nuclear antigens (PCNA), glutathione-S-transferase (GST), α-fetal protein (AFP) and albumin were stained immunohistochemically.

RESULTS: Typical and atypical types of ductular proliferation were observed in the portal tracts of the liver tissues in all 11 patients. The proliferating ductular cells were positive for CK8, CK19, OV6 and PCNA staining. Some atypical ductular cells displayed the morphological and immunohistochemical characteristics of hepatic oval cells. Some small hepatocyte-like cells were between hepatic oval cells and mature hepatocytes morphometrically and immunohistochemically.

CONCLUSION: The proliferating ductules in the liver of patients with severe chronic liver disease may have different origins. Some atypical ductular cells are actually activated hepatic oval cells. Atypical ductular proliferation is related to hepatocyte regeneration and small hepatocyte-like cells may be intermediate transient cells between hepatic oval cells and mature hepatocytes.