Late HBsAg seroreversion of mutated hepatitis B virus after bone marrow transplantation

Hepatitis B virus reactivation: overview and management

Hepatitis B virus (HBV) can hide in the liver in the form of covalently closed circular DNA. When the body’s immunity changes, HBV reactivation (HBV-R) can occur. The risk of HBV-R is determined by the complex interaction among virological factors, medication factors and host factors. However, many patients do not know that they are infected with HBV, and doctors often do not invest enough time to systematically evaluate the patient’s HBV-R risk factors before immunosuppressive treatment. Therefore, HBV clinical screening should be vigorously promoted to achieve early detection and early prevention for patients with high risk of HBV-R. The mechanism, clinical features, risk factors, HBV-R under different disease etiologies, prevention and treatment of HBV-R were summarized to improve the in-depth understanding and awareness.

Roles of Hepatitis B Virus Mutations in the Viral Reactivation after Immunosuppression Therapies

Reactivation of hepatitis B virus (HBV) is a major problem in patients receiving chemotherapy for malignant diseases or immunosuppression therapies. It has been thought that a reduction in the immune responses might result in the reactivation of HBV replication from covalently closed circular DNA (cccDNA) residing in hepatocytes. However, not only the host’s immune status, but also viral mutations have been reported to be associated with reactivation. Especially, several case reports about amino acid mutations in hepatitis B surface antigen (HBsAg) that escape from immune reactions have been reported, and recent reports showed that the frequencies of such mutations are higher than previously expected. In this review, we summarize the characteristics of viral mutations, including immune escape mutations in HBV-reactivated patients, and discuss their significance.

Adoptive donor immunity protects against resolved hepatitis B virus reactivation after allogeneic haematopoietic stem cell transplantation in the world's largest retrospective cohort study

Reactivation of hepatitis B virus (HBV) by reverse seroconversion (HBV-RS) after allogeneic haematopoietic stem cell transplantation (allo-HSCT) can occur in patients with resolved HBV infection (rHBV, defined as negative HBV surface antigen [HBsAg] and positive HBV core antibody), and may cause fatal hepatitis. To explore the risk factors, we retrospectively identified 817 consecutive patients who underwent allo-HSCT from 2005 to 2016 in this largest single centre cohort from National Taiwan Univerisity Hospital. Transplants using donors or recipients positive for HBsAg or HBV DNA were excluded, leaving 445 rHBV patients for analysis. The 3- and 5-year cumulative incidence of HBV-RS after allo-HSCT was 8·7% and 10·5%, respectively, at a median 16 months after allo-HSCT. All had concurrent HBV reactivation. HBV flares developed in 19% of HBV-RS cases, but none experienced hepatic failure. Neither did it impact non-relapse mortality or overall survival. Multivariate analysis revealed that patients with donor lacking hepatitis B surface antibody and extensive chronic graft-versus-host disease (cGVHD) have the highest risk for HBV-RS, with 5-year incidence of 24·2%. In conclusion, adoptive immunity transfer from the donor seems to have protective effects against HBV-RS, which may alter future donor selection algorithms, and combined with extensive cGVHD provides a good target for risk-adaptive HBV prophylaxis.

HBV reactivation in allogeneic stem cell transplant recipients: Risk factors, outcome, and role of hepatitis B virus mutations

Hepatitis B virus (HBV) reactivation (HBVr) in recipients of allogeneic hematopoetic stem cells (aHSCs) appears heterogeneously with respect to its frequency, manifestation, and outcome. The aim of this study was to present data from a large German cohort of recipients of aHSC transplantation (aHSCT), focusing on the incidence of HBVr in antibody to hepatitis B core antigen (anti‐HBc)‐positive aHSCT recipients, its clinical outcome, and the role of mutations in HBV. Between 2005 and 2015, 1,871 patients received aHSCT at University Hospital Essen. A follow‐up of at least 6 months after transplant was available in 55 patients who were anti‐HBc‐positive; clinical and virologic data were analyzed. The HBV genome was sequenced with next generation technology from serum samples of 8 patients with HBVr. Thirteen out of 55 (23.6%) patients developed HBVr at a median of 26 months after aHSCT. After initiation of antiviral treatment, complete HBV DNA suppression was achieved in 7/10 (70%) patients 1 to 40 months after HBVr. Nine of 13 patients had increased alanine aminotransferase; 3 patients had compromised coagulation and model for end‐stage liver disease scores of 18‐27, and 1 of these patients died due to liver failure 5 weeks after HBVr. As a risk factor for HBVr, we identified anti‐HBc signal to cut‐off ration (S/CO) ≥7.5 before transplantation. Complete HBV DNA suppression was achieved in 7/10 patients; therapy‐relevant mutations were found in 1 patient. In 4/8 patients, immune escape mutations were detected either as majority or minority variants. Conclusion: HBVr is common in anti‐HBc‐positive aHRCT recipients and can lead to severe hepatitis with compromised coagulation. The level of anti‐HBc S/CO before transplantation is a risk factor for HBVr. Complete virologic response under adequate antiviral treatment could not be achieved in all patients. (Hepatology Communications 2017;1:1014–1023)

Quantifying perinatal transmission of Hepatitis B viral quasispecies by tag linkage deep sequencing

Despite full immunoprophylaxis, mother-to-child transmission (MTCT) of Hepatitis B Virus still occurs in approximately 2–5% of HBsAg positive mothers. Little is known about the bottleneck of HBV transmission and the evolution of viral quasispecies in the context of MTCT. Here we adopted a newly developed tag linkage deep sequencing method and analyzed the quasispecies of four MTCT pairs that broke through immunoprophylaxis. By assigning unique tags to individual viral sequences, we accurately reconstructed HBV haplotypes in a region of 836 bp, which contains the major immune epitopes and drug resistance mutations. The detection limit of minor viral haplotypes reached 0.1% for individual patient sample. Dominance of “a determinant” polymorphisms were observed in two children, which pre-existed as minor quasispecies in maternal samples. In all four pairs of MTCT samples, we consistently observed a significant overlap of viral haplotypes shared between mother and child. We also demonstrate that the data can be potentially useful to estimate the bottleneck effect during HBV MTCT, which provides information to optimize treatment for reducing the frequency of MTCT.

Hepatitis B reactivation characterized by HBsAg negativity and anti-HbsAg antibodies persistence in haematopoietic stem cell transplanted patient after lamivudine withdrawal

Background

HBV reactivation is associated with high mortality rates in hematopoietic stem cell transplantation (HSCT) and prophylactic lamivudine (LMV) treatment is suggested to prevent this phenomenon. However, the duration of LMV treatment in HSCT patients is not fully defined and the time of immune recovery is considered the best parameter for a drug to be safely interrupted. In patients undergoing allogeneic HSCT, the time of immune recovery is not easy to define and may take years after transplantation and prolonged LMV treatments, which can lead to drug-resistant viral strains.

Case presentation

An anti-HBc-positive hematological patient who was undergoing prolonged immunosuppression and who experienced HBV reactivation 3 months after the suspension of a prolonged LMV prophylaxis is described. HBV-DNA matching an atypical serological profile characterized by HbsAg negativity and anti-HBs positivity was detected in the patient. The genotypic analysis of the HBV strain identified T127P, F170FL and S204R mutations of HbsAg, which can hinder HBsAg recognition in a diagnostic assay.

Conclusions

HBV reactivation in the HSCT host can be sustained by HBsAg viral variants with characteristics of altered immunogenicity that cannot be detected by usual laboratory tests. This clinical case description suggests the importance of screening for serum HBV-DNA levels in the diagnosis of HBV reactivation and monitoring HBV-DNA after prophylaxis suspension, particularly in HSCT subjects who have undergone prolonged periods of LMV treatment.

Risk factors and outcomes of hepatitis B virus reactivation in hepatitis B surface antigen negative patients with hematological malignancies

AIM

Current guidelines recommend all patients scheduled to receive chemotherapy should be screened for hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B virus core antigen (anti-HBc) status. However, still, more research is needed to identify the risk factors for hepatitis B virus (HBV) reactivation. We retrospectively investigated the incidence, risk factors and outcome of HBV reactivation in HBsAg negative patients with hematological malignancies.

METHODS

Seven hundred and thirty-eight HBsAg negative patients with hematological malignancies were included in the study. HBV reactivation was defined as reverse seroconversion of HBsAg (HBsAg reappearance). Risk factors, cumulative incidence and overall survival of HBV reactivation were analyzed.

RESULTS

Reactivation occurred in 23 of the 738 (3.1%) enrolled patients. As expected, the reactivation rate of the anti-HBc positive group was significantly higher than that of the anti-HBc negative group (5.4% vs 0.8%). Multivariate analysis indicated that loss of antibody to the hepatitis B surface antigen (anti-HBs) was an independent risk factor. Patients with acute lymphoblastic leukemia and multiple myeloma showed significantly higher reactivation rate than those with other diseases. The cumulative incidence of HBV reactivation after starting chemotherapy in the anti-HBc positive subgroup was 0.3% at 1 year, 1.7% at 2 years and 10.5% at 3 years.

CONCLUSION

Close monitoring of HBV markers, including anti-HBs, should be performed for longer than 24 months. Further study is needed to establish a strategy to prevent HBV reactivation after chemotherapy in HBsAg negative patients with hematological malignancies.

Hepatitis B reactivation in the setting of chemotherapy and immunosuppression - prevention is better than cure

Due to the inherent relationship between the immune system and the hepatitis B virus (HBV) in exposed and infected individuals, immunomodulation associated with the treatment of solid tumours, haematological malignancies and inflammatory disorders has been linked to HBV reactivation (HBVr). Reactivation of HBV infection in the setting of chemotherapy and immunosuppression may lead to fulminant liver failure and death, but there is a cumulative body of evidence that these are potentially preventable adverse outcomes. As chronic hepatitis B is largely asymptomatic but also endemic worldwide, clinicians caring for patients requiring chemotherapy or immunosuppression need to be vigilant of the potential for HBVr in susceptible individuals. Serological screening and prophylactic and pre-emptive antiviral treatment with a nucleos(t)ide analogue should be considered in appropriate settings. Hepatitis B prevalence is examined in this review article, as are the risks of HBVr in patients receiving chemo- and immunosuppressive therapy. Recommendations regarding screening, monitoring and the role of antiviral prophylaxis are outlined with reference to current international associations’ guidelines and the best available evidence to date.

Prospective long-term study of hepatitis B virus reactivation in patients with hematologic malignancy

BACKGROUND AND AIM

To elucidate the clinical characteristics of hepatitis B virus reactivation (HBV-R), we performed a prospective long-term study of patients with hematologic malignancy, including both hepatitis B virus (HBV) carriers and those with resolved HBV infection.

METHODS

Twenty-one patients with hematopoietic stem-cell transplants (HSCT) and 36 patients given rituximab-based chemotherapy were enrolled. Entecavir was administered prophylactically to eight patients with HBV surface antigen (HBsAg). HBV-DNA was measured every month in 49 patients with resolved HBV infection, and preemptive therapy was given to eight patients with HBV-R.

RESULTS

HBV-R developed in five (26%) of 19 patients with HSCT and three (10%) of 30 patients given rituximab-based chemotherapy. HBV-R occurred a median of 3 months (range: 2-10) after the end of rituximab-based chemotherapy and 22 months (range: 9-36) after HSCT. HBV-R did not develop in patients with an antibodies against HBsAg (anti-HBs) titer exceeding 200 mIU/mL at baseline. Mutations in the "a" determinant region with amino acid replacement were detected in four of the eight patients with HBV-R. Preemptive therapy prevented severe hepatitis related to HBV-R. Entecavir treatment was stopped in four patients with HBV-R. Since the withdrawal of entecavir, HBV-DNA has not been detected in two patients persistently positive for anti-HBs. No patient had fatal hepatitis.

CONCLUSIONS

Proper management of patients with HBsAg or resolved HBV infection prevented fatal hepatitis related to HBV-R in patients who received immunosuppressive or cytotoxic therapy. Entecavir could be safely discontinued in patients with HBV-R who had acquired anti-HBs.