Lamivudine prophylaxis and treatment of hepatitis B Virus-exposed recipients receiving reduced intensity conditioning hematopoietic stem cell transplants with alemtuzumab

Hepatitis B Virus Reactivation in Non-Liver Solid Organ Transplantation: Incidence and Risk Analysis

INTRODUCTION

Hepatitis B virus reactivation (HBVr) can occur in solid organ transplant (SOT) recipients with previously inactive hepatitis B virus (HBV) infection. Previous studies have reported that HBVr is generally less than 10% in nonliver SOT recipients with past HBV infection.

METHODS

We conducted a retrospective study from January 2018 to August 2023 at Mayo Clinic sites in Arizona, Florida, and Minnesota. We examined the antiviral prophylaxis strategy used and the characteristics of HBVr in hepatitis B core antibody-positive (HBcAb +) nonliver SOT adult recipients. Past HBV infection was defined as HBcAb + / hepatitis B surface antigen (HBsAg) -. Chronic HBV infection was defined as HBcAb + / HBsAg +.

RESULTS

A total of 180 nonliver SOT recipients were identified during the study period. Indefinite antiviral prophylaxis was utilized in 77 recipients, and none developed HBVr after transplantation. In 103 recipients without antiviral prophylaxis, the incidence of HBVr was 12% (12/97) and 33% (2/6) in those with past HBV infection and chronic HBV infection. The incidence of HBVr in patients with past HBV infection is 16% (8/50), 15% (3/20), and 5% (1/22) in kidney, heart, and lungs, respectively. HBVr was more frequent in those who received alemtuzumab. Among 14 recipients with HBVr, none had HBV-associated liver failure or death.

CONCLUSIONS

Our study observed a higher rate of HBVr (12%) in nonliver SOT recipients with past HBV infection compared to the previous studies. Further studies are needed to identify predictors of HBVr in nonliver SOT recipients and optimize antiviral prophylaxis guidance.

Hepatitis B Virus Infection in Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation

Considering a steady increase in the number of allogeneic hematopoietic stem cell transplantations (allo-HSCT) worldwide and the significant proportion of the world’s population that has been exposed to hepatitis B virus (HBV) infection, HBV reactivation following allo-HSCT remains an important issue for post-transplant morbidity and mortality. Antiviral prophylaxis can reduce HBV replication, severity of HBV-related hepatitis, and mortality; therefore, identification of patients at risk is crucial. It is recommended that all recipients and donors should be screened for active or prior HBV infection, including HBsAg, antiHBc, and antiHBs. Adoptive immunity transfer from the donor seems to have protective effects against HBV reactivation. Antiviral prophylaxis should be initiated in all HBsAg-positive patients. HBsAg-negative, antiHBc-positive patients remain at risk; therefore, antiviral prophylaxis should be considered if baseline serum HBV DNA is detectable. In HBsAg-negative, antiHBc-positive patients without detectable HBV DNA, close monitoring of viral load with an on-demand therapy is necessary. Entecavir or tenofovir rather than lamivudine are more appropriate for the emergence of lamivudine resistance. The treatment duration remains unclear, with 6- to 12-month therapy after cessation of immunosuppressive therapy commonly recommended. Here we review the updated evidence and recent recommendations regarding HBV reactivation in patients undergoing allo-HSCT for individualized therapy.

The Disease-Modifying Therapies of Relapsing-Remitting Multiple Sclerosis and Liver Injury: A Narrative Review

In this narrative review, we analyze pre-registration and post-marketing data concerning hepatotoxicity of all disease-modifying therapies (DMTs) available for the treatment of relapsing-remitting multiple sclerosis, including beta interferon, glatiramer acetate, fingolimod, teriflunomide, dimethyl fumarate, cladribine, natalizumab, alemtuzumab, and ocrelizumab. We review the proposed causal mechanisms described in the literature and we also address issues like use of DMTs in patients with viral hepatitis or liver cirrhosis. Most data emerged in the post-marketing phase by reports to national pharmacovigilance agencies and published case reports or case series. Serious liver adverse events are rare, but exact incidence is largely unknown, as are predictive factors. Unfortunately, none of the DMTs currently available for the treatment of multiple sclerosis is free of potential hepatic toxic effects. Cases of acute liver failure have been reported for beta-interferon, fingolimod, natalizumab, alemtuzumab, and ocrelizumab by different mechanisms (idiosyncratic reaction, autoimmune hepatitis, or viral reactivation). Patients with multiple sclerosis should be informed about possible hepatic side effects of their treatment. Most cases of liver injury are idiosyncratic and unpredictable. The specific monitoring schedule for each DMT has been reviewed and the clinician should be ready to recognize clinical symptoms suggestive for liver injury. Not all DMTs are indicated in cirrhotic patients. For some DMTs, screening for hepatitis B virus and hepatitis C virus is required before starting treatment and a monitoring or antiviral prophylaxis schedule has been established. Beta interferon, glatiramer acetate, natalizumab, and alemtuzumab are relatively contraindicated in autoimmune hepatitis due to the risk of disease exacerbation.

Reactivation of hepatitis B virus infection in patients with hematologic disorders

Hepatitis B reactivation is the reappearance or rise of hepatitis B virus (HBV) DNA in patients with past or chronic HBV infection, usually occurring in the context of immunosuppression. HBV reactivation has been most commonly reported in patients with hematologic disorders, with potentially serious and life-threatening consequences. In this review, we discuss the basis and presentation of HBV reactivation, and risk factors in terms of the host, the virus and the immunosuppression regimen, including newer agents used to manage hematologic malignancies. We overview the management of HBV reactivation, highlighting an up-dated recommendation on the use of newer nucleoside and nucleotide analogs, such as tenofovir and entecavir, for antiviral prophylaxis.

Efficacy of lamivudine prophylaxis in preventing hepatitis B virus reactivation in patients with resolved infection undergoing allogeneic SCT and receiving rituximab

PURPOSE

Hepatitis B virus (HBV) reactivation during immunosuppressive therapy is common in patients with hematological malignancies, even in case of resolved infection. Prophylaxis of HBV reactivation is universally recommended in stem cell transplant (SCT) recipients and patients treated with anti-CD20 agents (i.e., rituximab). Despite its well-established favorable safety profile, lamivudine (LAM) use in prophylaxis has been debated because of the possible emergence of resistant viral strains. The aim of this study was to investigate the efficacy of LAM in preventing HBV reactivation in allogeneic SCT recipients with a resolved HBV infection.

METHODS

Patients who received first allogeneic SCT in years 2009-2016 were evaluated. Sixty-three patients with resolved infection received LAM prophylaxis and were included in the study. Baseline and post-SCT characteristics were recorded, including rituximab exposure, length of LAM prophylaxis, and time from transplant to the last clinical and virological follow-up.

RESULTS

Overall, 39 patients (62%) were male, 39 (62%) had acute myeloid leukemia, 38 (60%) received transplant from haploidentical donor, 29 (53%) received myeloablative conditioning, and 15 (24%) received rituximab post-transplant. Median clinical follow-up was 24 months after SCT (range 0.3-97); median virological follow-up 16 months (range 0.3-78), and median length of LAM prophylaxis of 14.5 months (range 0.3-78). No patient experienced HBV reactivation while on LAM prophylaxis. One patient experienced reactivation 8 months after discontinuing prophylaxis.

CONCLUSIONS

In this high-risk population, LAM prophylaxis was effective in preventing HBV reactivation in patients with resolved infection. It should be considered a reasonable first-line prophylactic agent to be administered in this setting.

Antiviral prophylaxis during chemotherapy or immunosuppressive drug therapy to prevent HBV reactivation in patients with resolved HBV infection: a systematic review and meta-analysis

BACKGROUND

Until recently, the role of antiviral prophylaxis in preventing hepatitis B virus (HBV) reactivation during immunosuppressive therapy or chemotherapy in patients with resolved HBV infection was unclear. The aim of the study reported here was to compare the efficacy of antiviral prophylaxis versus that of non-prophylaxis in resolved HBV-infected patients undergoing chemotherapy or immunosuppressive therapy.

METHODS

PubMed, the Cochrane library, and the ClinicalTrials.gov website were searched from inception until December 2017. Studies comparing reactivation in prophylaxis versus non-prophylaxis in patients undergoing immunosuppressive therapy or chemotherapy were included. The meta-analysis was performed to calculate the relative risk (RR) and the pooled estimates.

RESULTS

A meta-analysis was conducted of 13 studies (2 randomized controlled trials [RCTs] and 11 cohort studies). The summary RR for HBV reactivation was 0.47 (95% confidence interval [CI] 0.13-1.69) for antiviral prophylaxis versus non-prophylaxis. Both of the RCTs included in the meta-analysis enrolled patients treated with rituximab. Subgroup analyses showed that the two RCTs ± high-quality cohort studies showed a decreased risk of HBV reactivation among the antiviral prophylaxis groups (RCT 1: RR 0.13, 95% CI 0.02-0.70; P = 0.02; RCT 2: 0.28, 95% CI 0.08-0.98; P = 0.05). Subgroup analyses further showed that the cohort studies did not support an association between the antiviral prophylaxis groups and HBV reactivation (RR 0.62, 95% CI 0.14-2.83; P = 0.54); adjusting for confounding factors, such as detectable anti-HBs antibodies, failed to produce a significant association (RR,0.29, 95% CI 0.07-1.28; P = 0.10).

CONCLUSION

Our meta-analyses did not show an association between antiviral prophylaxis use and risk of HBV reactivation. As using only the RCTs ± high-quality cohort studies data rendered this association significant, clinicians can consider providing antiviral prophylaxis to patients with resolved HBV infection who are undergoing rituximab-based therapy.

Prophylaxis for Hepatitis B Virus Reactivation after Allogeneic Stem Cell Transplantation in the Era of Drug Resistance and Newer Antivirals: A Systematic Review and Meta-Analysis

Patients undergoing allogenic hematopoietic stem cell transplantation (allo-HSCT) are at a very high risk of hepatitis B virus reactivation (HBVr). Lamivudine is commonly used as prophylaxis against HBVr in high-risk patients undergoing allo-HSCT. Unfortunately, its efficacy is diminishing due to the development of HBV mutant drug-resistant strains. With the availability of newer antiviral agents such as entecavir, telbivudine, adefovir, and tenofovir, it is important to assess their role in HBVr prophylaxis. A comprehensive search of 7 databases was performed to evaluate efficacy of antiviral prophylaxis against HBVr in allo-HSCT patients (PubMed/Medline, Embase, Scopus, Cochrane Library, Web of Science, CINAHL, and ClinicalTrials.gov (June 21, 2017)). We identified 10 studies, with 2067 patients undergoing allo-HSCT; these primarily evaluated the use of lamivudine and entecavir as prophylaxis against HBVr in patients undergoing allo-HSCT because there were little or no data about adefovir, telbivudine, or tenofovir as prophylaxis in this specific patient population. Thus, included studies were categorized into 2 main prophylaxis groups: lamivudine and entecavir. Results of our meta-analysis suggest that entecavir is very effective against HBVr, although further clinical trials are required to test efficacy of new antivirals and explore the emerging threat of drug resistance.

Characteristics, Prevention, and Management of Hepatitis B Virus (HBV) Reactivation in HBV-Infected Patients Who Require Immunosuppressive Therapy

Hepatitis B virus (HBV) reactivation becomes a challenging issue with increasing use of immunosuppressive agents and cytotoxic chemotherapy for varied medical conditions, including cancer. The spectrum of HBV reactivation in the setting of immunosuppression may vary from asymptomatic reactivation to liver failure leading to death. HBV reactivation can hamper the course of planned therapies and diminish the effects of therapies; thus, it adversely affects the prognosis of the original disease and the survival of the patients. There is mounting evidence that HBV reactivation can be prevented and managed if patients are screened to determine their risk for HBV reactivation and are treated prophylactically before therapy with immunosuppressive agents or cytotoxic chemotherapy is initiated. In this article, we review the diagnostic criteria and clinical outcomes of HBV reactivation, discuss how immunosuppressive therapy may influence the risk of HBV reactivation, and outline strategies to prevent HBV reactivation.

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.

Prevention and management of hepatitis B virus reactivation in patients with hematological malignancies treated with anticancer therapy

Hepatitis due to hepatitis B virus (HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximab-containing therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc). Patients found to be positive for HBsAg should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving high-risk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBsAg-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies.

Prevention of Hepatitis B reactivation in the setting of immunosuppression

Advances in the treatment of malignant and inflammatory diseases have developed over time, with increasing use of chemotherapeutic and immunosuppressive agents of a range of drug classes with varying mechanism and potency in their effects on the immune system. These advances have been met with the challenge of increased risk of hepatitis B virus (HBV) reactivation in susceptible individuals. The magnitude of risk of HBV reactivation is associated with the individual’s HBV serological status and the potency and duration of immunosuppression. Individuals with chronic hepatitis B (CHB) and previously infected but serologically cleared HBV infection are both susceptible to HBV reactivation. HBV reactivation in the setting of immunosuppression is a potentially life threatening condition leading to liver failure and death in extreme cases. It is important to recognize that HBV reactivation in the setting of immunosuppression is potentially preventable. Therefore, identification of patients at risk of HBV reactivation and institution of prophylactic antiviral therapy prior to initiation of immunosuppression is essential.

Hepatotoxicity of targeted therapy for cancer

INTRODUCTION

Understanding the mechanism of DILI with MTA, and how to avoid and manage these toxicities is essential for minimising inferior cancer treatment outcomes. An organised and comprehensive overview of MTA-associated hepatotoxicity is lacking; this review aims to fill the gap.

AREAS COVERED

A literature review was performed based on published case reports and relevant studies or articles pertaining to the topics on PubMed. Food and Drug Administration drug information documents and search on the US National Library of Medicine LiverTox database was performed for all relevant MTA.

EXPERT OPINION

MTA-associated hepatotoxicity is common but rarely fatal. The pattern of hepatotoxicity is predominantly idiosyncratic. Pharmacogenomics show potential in predicting patients at risk of poorly metabolising or developing immunoallergic responses to MTA, but prospective data is scant. Preventing reactivation of viral hepatitis using anti-viral drugs, and avoidance of drug combinations at high risk of negative interactions are the most readily preventable measures for DILI.

Lymphoproliferative Disease and Hepatitis B Reactivation: Challenges in the Era of Rapidly Evolving Targeted Therapy

Reactivation of hepatitis B virus (HBV) is a known complication that occurs in patients receiving chemotherapy especially for malignant lymphoma. The increased risk in lymphoma patients parallels the potency of the immunosuppressive treatment regimens that are provided. B-cell-depleting therapy such as anti-CD20 monoclonal antibodies, especially when combined with conventional chemotherapy, significantly increases the risk of HBV reactivation, even in patients with resolved HBV infection. The first reports of HBV reactivation with anti-CD20 therapy emerged only 4 years after its US Food and Drug Administration approval. Today, these drugs carry alert warnings on the risk of hepatic dysfunction and reactivation of HBV infection. Many other new/novel agents active against lymphoma have emerged since then, targeting the different pathways involved in lymphoma pathogenesis, including histone deacetylase inhibitors, antibody-drug conjugates, and proteasome inhibitors. These various drugs have differing depths and mechanisms of immunosuppression, necessitating due diligence when administrating these compounds to prevent infective complications such as HBV reactivation, which can lead to liver failure and death. This review focuses on HBV reactivation with non-Hodgkin lymphoma treatment, in particular with the various approved novel agents. We also discuss the current recommendations for screening non-Hodgkin lymphoma patients for HBV and the role of prophylactic antiviral therapy during and after immunosuppressive treatment.

Hepatitis B virus and hepatitis C virus treatment and management in patients receiving immune-modifying agents

PURPOSE OF REVIEW

To increase awareness and review the management of chronic viral hepatitis in individuals treated with immune-modifying agents to avoid potentially severe consequences.

RECENT FINDINGS

Hepatitis B virus (HBV) reactivation has been reported with a wide variety of immunosuppressive regimens ranging from corticosteroids to cytotoxic chemotherapy. In the rheumatology field, reactivation is best studied with anti-tumor necrosis factor-alpha agents and may occur even in individuals with 'resolved' HBV infection. These complications can be prevented with the use of well tolerated pre-emptive antiviral agents. Treatment of reactivation after it occurs is much less effective. Unlike HBV, acute deterioration is rare with immunosuppression in patients with hepatitis C virus (HCV) and prophylactic therapy is not indicated in these patients. However, patients should undergo evaluation for staging of liver disease preferably before immunosuppression because of the risk of drug-induced liver injury and also rheumatological complications, such as cryoglobulinemia.

SUMMARY

HBV and HCV remain enormous global health problems with over 500 million people infected worldwide. Neither virus is cytopathic with liver damage and control of viral replication caused by the host immune response. With the increasing number and types of immunomodulatory therapies, HBV reactivation is becoming an increasingly recognized issue in many areas of medicine, particularly rheumatology. Unfortunately, screening rates are low, partially because of unclear clinical guidelines. HCV may also complicate immunomodulatory therapy, particularly if cirrhosis is present. The management of rheumatology patients with HBV and HCV infection is discussed with a focus on whom to screen and whom to treat to prevent consequences of these often unrecognized conditions.

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.

Prophylactic antiviral therapy in allogeneic hematopoietic stem cell transplantation in hepatitis B virus patients

AIM: To investigate the timing, safety and efficacy of prophylactic antiviral therapy in patients with hepatitis B virus (HBV) infection undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT).

METHODS: This prospective study recruited a total of 57 patients diagnosed with malignant hematological diseases and HBV infection at the First Affiliated Hospital of Sun Yat-sen University between 2006 and 2013. The patients were classified as hepatitis B surface antigen (HBsAg)-positive or HBsAg-negative/ antiHBc-positive. Patients were treated with chemotherapy followed by antiviral therapy with nucleoside analogues. Patients underwent allo-HSCT when serum HBV DNA was < 10³ IU/mL. Following allo-HSCT, antiviral therapy was continued for 1 year after the discontinuation of immunosuppressive therapy. A total of 105 patients who underwent allo-HSCT and had no HBV infection were recruited as controls. The three groups were compared for incidence of graft-vs-host disease (GVHD), drug-induced liver injury, hepatic veno-occlusive disease, death and survival time.

RESULTS: A total of 29 of the 41 subjects with chronic GVHD exhibited extensive involvement and 12 exhibited focal involvement. Ten of the 13 subjects with chronic GVHD in the HBsAg(-)/hepatitis B core antibody(+) group exhibited extensive involvement and 3 exhibited focal involvement. Five of the 10 subjects with chronic GVHD in the HBsAg(+) group exhibited extensive involvement and 5 exhibited focal involvement. The non HBV-infected group did not differ significantly from the HBsAg-negative/antiHBc-positive and the HBsAg-positive groups which were treated with nucleoside analogues in the incidence of graft-vs-host disease (acute GVHD; 37.1%, 46.9% and 40%, respectively; P = 0.614; chronic GVHD; 39%, 40.6% and 40%, respectively; P = 0.98), drug-induced liver injury (25.7%, 18.7% and 28%, respectively; P = 0.7), death (37.1%, 40.6% and 52%, respectively; P = 0.4) and survival times (P = 0.516). One patient developed HBV reactivation (HBsAg-positivity) due to early discontinuation of antiviral therapy.

CONCLUSION: Suppression of HBV DNA to < 10³ IU/mL before transplantation, continued antiviral therapy and close monitoring of immune markers and HBV DNA after transplantation may assure the safety of allo-HSCT.

Hepatitis B and Hepatitis C Reactivation in the Biologic Era

Hepatitis B (HBV) and hepatitis C (HCV) reactivation may occur after the use of biologic agents. During the last decade, utilization of biologics has changed the fate of many treated for cancer, autoimmune and connective tissue disease, maintenance of transplanted organs, and the prevention of graft-versus-host disease among others. HBV reactivation has been reported in up to 50% of HBV carriers undergoing immunosuppressive therapy, and there is emerging data pointing towards an increased risk for HCV reactivation. If reactivation of HBV and HCV occurs, the spectrum of clinical manifestations can range from asymptomatic hepatitis flares to hepatic decompensation, fulminant hepatic failure, and death. Therefore, identifying patients at risk and early diagnosis are imperative to decrease significant morbidity and mortality. The purpose of this article is to review the pathophysiology of the reactivation of HBV and HCV infection in patients receiving biologic therapies and the approaches used to diagnose, prevent, and treat HBV and HCV reactivation.

[Hepatitis B virus infection in pregnancy and the immunosuppressed patient]

Hepatitis B virus (HBV) infection continues to be a major public health problem worldwide. Although treatment indications are well established in clinical practice guidelines, there are some risk groups, such as pregnant women and immunosuppressed patients, who require different and specific management of HBV infection. In pregnant women, treatment indication should be individualized and the risk of HBV transmission to the newborn evaluated because cases of vertical transmission continue to be reported, despite active and passive immunoprophylaxis. In patients receiving immunosuppressive therapy, HBV reactivation is associated with high morbidity and mortality, even in patients with past HBV infection, highlighting the importance of screening and the need to evaluate prophylactic therapy in some cases.

Management of patients with hepatitis B who require immunosuppressive therapy

Patients with chronic HBV infection are at risk of reactivation of HBV should they require immunosuppressive therapies for a variety of clinical settings, including chemotherapy for patients with cancer, immunosuppression for solid organ and stem cell transplant recipients, and use of anti-CD20 antibodies, TNF inhibitors, or corticosteroids in patients with oncological, gastrointestinal, rheumatological or dermatological conditions. The key to preventing HBV reactivation is the identification of patients with HBV infection prior to immunosuppressive therapy, initiation of prophylactic antiviral therapy in patients at moderate or high risk of HBV reactivation, and close monitoring of other patients so that antiviral therapy can be initiated at the first sign of HBV reactivation. Unfortunately, many patients infected with HBV are unaware of their infection or risk factors, and physicians often do not have sufficient time to systematically assess patients for risk factors for HBV prior to starting immunosuppressive therapy. In this article, we review the incidence, risk factors and outcomes of HBV reactivation, and the efficacy of antiviral therapy in preventing its occurrence. We also propose an algorithm for managing patients with HBV infection who require immunosuppressive therapy.

Liver abnormalities in the immunosuppressed

The immunosuppressed state may arise due to medical illness or drug therapy, which can result in a diverse array of liver derangements. This article discusses the commonly-encountered immunosuppressed conditions and the associated specific liver diseases. Due to the frequency of blood-borne viral disease globally, viral hepatitis (hepatitis B and C) during chemotherapy, transplantation and the increasingly utilised biological therapies for autoimmune disorders is discussed. An overview of human immunodeficiency virus co-infection with hepatitis B and C is provided. This article aims to highlight the variety of liver diseases which can occur in clinically relevant, particularly iatrogenic, immunosuppressed conditions, and summarise learning and practice points for clinicians. Recognition and prevention of viral liver disease is crucial and early involvement of experts prior to administration of immunosuppressive therapy is advised.

Hepatitis B in immunosuppressed cancer patients: pathogenesis, incidence and prophylaxis

BACKGROUND

Hepatitis B virus (HBV) reactivation in immunosuppressed cancer patients is a serious clinical problem for HBV carriers undergoing chemotherapy, because it may result in severe liver injury and prevent completion of life-saving treatment of the underlying malignant disease.

DESIGN

We reviewed the literature on the incidence, pathogenesis and management of hepatitis B in immunosuppressed cancer patients. The role of primary prophylaxis has also been reviewed.

RESULTS

Patients with a previous HBV infection (negative for hepatitis B surface antigen [HBsAg], and positive for both hepatitis B core antibody [anti-HBc] and/or hepatitis B surface antibody [HBsAb]) can experience HBV reactivation. All guidelines support screening of patients with cancer who are about to undergo potentially immunosuppressive therapy, even if the ASCO provisional clinical opinion considers the screening for patients at heightened risk for chronic HBV infection or if undergoing highly immunosuppressive therapy, as hematopoietic cell transplantation and regimens including rituximab. Several meta-analyses support the prophylactic role of lamivudine in preventing HBV reactivation. Most of studies evaluated retrospectively or, if prospectively designed, compared the effect of prophylactic antiviral therapy against historical controls.

CONCLUSION

Screening for HBV should be considered before chemotherapy. Prophylaxis with lamivudine can reduce the incidence of HBV reactivation as well as HBV-related morbidity and mortality. Unsolved issues include the role of antiviral agent with higher potency and less resistance, how to monitor patients for reactivation and when to stop prophylaxis.

Hepatitis B virus infection: pathogenesis, reactivation and management in hematopoietic stem cell transplant recipients

Hepatitis B virus (HBV) is a partially double stranded DNA virus that can integrate into host cell chromosomes as covalently closed circular DNA forms. HBV reactivation following hematopoietic stem cell transplantation in recipients with evidence of past HBV exposure, as well as exacerbation of a current HBV infection in HBV carrier recipients, secondary to chemotherapy and post-transplant immunosuppression that affect both humoral and cell-mediated control of HBV infection, are well documented in the literature. Management options include HBV-DNA screening and antiviral prophylaxis. Nucleos(t)ide analogues have been used at the start of chemotherapy and pretransplantation, with the course continuing for 6 months. However, depending on the serum HBV-DNA level, the antiviral agent might be given until a therapeutic end point is reached.

Infections in Leukemia and Hematopoietic Stem Cell Transplantation

Infections are one of the most common complications in patients diagnosed with leukemia and serve as a major obstacle to treatment. Through the early 1970s, infections were the most common cause of death in patients diagnosed with acute leukemia, but improvement in treatment and supportive care over the past few decades, coupled with expanded prophylaxis and prevention regimens, have led to reduction in both the frequency and severity of infections. Regardless, due in part to an aging cancer population and the diversity of cancer treatments and procedures, infectious diseases remain a major cause of morbidity and mortality in patients with leukemia.

Current trends in management of hepatitis B virus reactivation in the biologic therapy era

Hepatitis B virus (HBV) reactivation represents an emerging cause of liver disease in patients undergoing treatment with biologic agents. In particular, the risk of HBV reactivation is heightened by the use monoclonal antibodies, such as rituximab (anti-CD20) and alemtuzumab (anti-CD52) that cause profound and long-lasting immunosuppression. Emerging data indicate that HBV reactivation could also develop following the use of other biologic agents, such as tumor necrosis factor (TNF)-α inhibitors. When HBV reactivation is diagnosed, it is mandatory to suspend biologic treatment and start antiviral agents immediately. However, pre-emptive antiviral therapy prior to monoclonal antibody administration is crucial in preventing HBV reactivation and its clinical consequences. Several lines of evidence have shown that risk of HBV reactivation is greatly reduced by the identification of high-risk patients and the use of prophylactic antiviral therapy. In this article, we discuss current trends in the management of HBV reactivation in immunosuppressed patients receiving biologic therapy, such as rituximab, alemtuzumab and TNF-α antagonists.

HBV disease: HBsAg carrier and occult B infection reactivation in haematological setting

HBV reactivation in patients with haematological malignancies undergoing chemoimmunotherapy is a serious and frequent complication. This is linked to either the high frequency of inactive HbsAg carriers and occult B infection among oncohaematological patients or the profound immunosuppression caused by high dose chemotherapy, monoclonal antibody therapy or auto- and allo-haematopoietic stem cell (HSC) transplantations. Identifying the patients at risk is mandatory in this clinical setting and prophylaxis with antiviral drugs or close monitoring may reduce and/or eliminate the HBV reactivation risk and the serious consequences. In general, preemptive anti-HBV therapy is more effective than treatment at reactivation. Prompt lamivudine prophylaxis should be given to HBsAg positive patients (inactive carriers) undergoing chemotherapy-immunochemotherapy and continued after cessation of immunosuppression even though long-term lamivudine therapy involves a risk of developing drug resistance. Use of newer anti-HBV agents may be considered. HBV reactivation has also been observed in occult B infection (HBcAb positive) and the optimal management of this group of patients requires special attention.

Prevention and treatment of hepatitis virus infections in hematopoietic stem cell transplant recipients

Infections with Hepatitis viruses B and C pose major problems both short and long term respectively after HSCT. The key to prevention for Hepatitis B disease remains vaccination for HBV-naïve patients and judicial use of anti-viral therapy in both pre- and post-transplant settings for HBV-infected patients. HBsAg positive grafts to HBV-naïve recipients result in transmission of the virus in about 50%. The newer anti-viral agents have enabled effective treatment of post-transplant patients who might be lamivudine-resistant or might develop so. Selecting a previously infected donor who has high titres of surface antibody for HBsAg positive patients gives the best chance for immunological clearance. The most challenging aspect of preventing HBV reactivation remains the duration of anti-viral therapy and timing of its withdrawal as most reactivations and often fatal ones occur after this period. Hepatitis C, on the other hand affects long-term survival with early onset of fibrosis and cirrhosis. Early effect of Hepatitis C virus on the immune system remains conjectural. The standard combination therapy seems to be effective, but data on this front remains sparse, as in the case of the use of newer antiviral agents. HSCT from HCV infected grafts result in more consistent transmission of the virus and pre-donation treatment of donors should be undertaken to render them non-viremic, if possible. The current understanding and recommendations regarding prevention and management of these infections in HSCT recipients are discussed.

How I treat and monitor viral hepatitis B infection in patients receiving intensive immunosuppressive therapies or undergoing hematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation is a serious but preventable complication of immunosuppression. Full HBV serologic profile must be obtained from all patients receiving intensive immunosuppressive therapy. In general, preemptive anti-HBV therapy is more effective than giving treatment after development of reactivation. Prompt lamivudine therapy should be given to at-risk patients who are hepatitis B surface antigen (HBsAg)-positive. It is recommended that lamivudine be continued until at least 6 months after the cessation of immunosuppression. Some patients requiring a longer duration of lamivudine therapy are at risk of developing drug resistance. The newer anti-HBV agents are effective in overcoming lamivudine resistance. Early use of these agents may be considered. HBV reactivation was observed in HBsAg-negative patients with occult HBV infection (HBV DNA-positive) who are on heavy immunosuppression. The optimal management of this group of patients is unclear. For patients receiving allogeneic HSC transplants, the HBV status of the donors requires special attention. To minimize the risk of transmission of infection to recipients, HBsAg-positive donors should receive adequate anti-HBV therapy before HSC donation. As the result of adoptive immune transfer, clearance of HBsAg is observed in HBsAg-positive patients receiving HSC transplants from donors who are positive for hepatitis B surface and core antibodies.

Deficiencies in the standardization and sensitivity of diagnostic tests for hepatitis B virus

The patterns of hepatitis B virus (HBV) markers described in textbooks apply to acute and chronic infection with wild-type HBV. Deviations from these patterns occur in the very early phase, in low-level (or occult) infection and under immunosuppression. Variability may originate from the virus, the host or the test kits. In order to obtain a reliable diagnosis under these conditions, tests for all three markers of HBV infection have to be applied: HBsAg, HBV DNA and anti-HBc. All tests should be as sensitive as feasible, but even then occult infection may be missed. Reliable detection of occult or mutated HBV is particularly important in blood and organ donors and in patients before or with immunosuppression.

Management of hepatitis B: summary of a clinical research workshop

Chronic hepatitis B is caused by persistent infection with the hepatitis B virus (HBV), a unique DNA virus that replicates through an RNA intermediate produced from a stable covalently closed circular DNA molecule. Viral persistence appears to be due to inadequate innate and adaptive immune responses. Chronic infection has a variable course after several decades resulting in cirrhosis in up to one-third of patients and liver cancer in a proportion of those with cirrhosis. Sensitive assays for HBV DNA levels in serum have been developed that provide important insights into pathogenesis and natural history. Therapy of hepatitis B is evolving. Peginterferon induces long-term remissions in disease in one-third of patients with typical hepatitis B e antigen (HBeAg) positive chronic hepatitis B, but a lesser proportion of those without HBeAg. Several oral nucleoside analogues with activity against HBV have been shown to be effective in suppressing viral levels and improving biochemical and histological features of disease in a high proportion of patients with and without HBeAg, at least in the short term. What is uncertain is which agent or combination of agents is most effective, how long therapy should last, and which criteria should be used to start, continue, switch or stop therapy. Long-term therapy with nucleoside analogues may be the most appropriate approach to treatment, but the expense and lack of data on long-term safety and efficacy make recommendations difficult. Clearly, many basic and clinical research challenges remain in defining optimal means of management of chronic hepatitis B.