Kinetic profiles and management of hepatitis B virus reactivation in patients with immune-mediated inflammatory diseases

Anti-rheumatic drug-induced hepatitis B virus reactivation and preventive strategies for hepatocellular carcinoma

To date, an estimated 3 million people worldwide have been infected with chronic hepatitis B virus (HBV). Although anti-HBV therapies have improved the long-term survival profile of chronic carriers, viral reactivation still poses a significant challenge for preventing HBV-related hepatitis, hepatocellular carcinoma (HCC), and death. Immuno-modulating drugs, which are widely applied in managing rheumatic conditions, are commonly associated with HBV reactivation (HBVr) as a result of drug-induced immune suppression. However, there are few reports on the risk of HBVr and the medication management plan for HBV carriers, especially rheumatic patients. In this review, we summarize immuno-modulating drug-induced HBVr during rheumatoid therapy and its preventive strategies for HBVr-induced liver diseases, especially cirrhosis and HCC. These findings will assist with developing treatments for rheumatic patients, and prevent HBV-related cirrhosis and HCC.

Rituximab treatment of ANCA-associated vasculitis

INTRODUCTION

Rituximab, an anti-B-cell biological therapy, has been investigated in several clinical trials on antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs).

AREAS COVERED

In this paper, the clinical trials and open-label studies on rituximab efficacy and safety in treating AAVs are reviewed.

EXPERT OPINION

Rituximab achieved high remission-induction and sustained-maintenance rates for patients with these severe diseases, thereby challenging the cornerstone treatment of corticosteroids and cyclophosphamide followed by azathioprine. Rituximab should be used as first-line therapy with corticosteroids to induce remission of severe AAVs, especially in situations in which cyclophosphamide may be problematic (relapse after cyclophosphamide, women of childbearing age, risk of malignancy). Cyclophosphamide indications are likely to be restricted in the future. Whenever possible, rituximab should be preferred to azathioprine to maintain remission. The current maintenance regimen has been extended to at least 18 months but its optimal duration remains unknown and recent data suggest the possibility to extend treatment to 4 years. Future challenges include defining the best dose regimen: at present, different schedules are used as alternatives to those recognized as standards by health authorities. In addition, it remains to identify which patients will benefit the most from long-term retreatment: potentially those with relapsing disease or anti-proteinase-3 ANCA-positivity.

Reactivation of hepatitis B virus infection in rheumatic diseases: risk and management considerations

In patients with rheumatic diseases undergoing immunosuppressive treatment, hepatitis B virus reactivation (HBVr) has been long recognized as a major treatment-related adverse event with substantial morbidity and mortality. Because HBVr is easily preventable with appropriate screening and monitoring strategies, and, when indicated, prophylactic antiviral treatment, awareness of this complication is of the utmost importance, especially in the era of biologic treatments. As a condition, it continues to be topical, in view of the emergence of novel classes of immunosuppressive drugs (i.e. Janus kinase inhibitors) acquiring licenses for a variety of rheumatic diseases. The class-specific risk of these agents for HBVr has not yet been determined. Moreover, ambiguity still exists for the management of patients planned to be treated with traditional agents, such as cyclophosphamide and glucocorticoids, particularly in the setting of resolved HBV infection. Clinicians in the field of rheumatic diseases should be tailoring their practice according to the host's profile and treatment-specific risk for HBVr. In this review, the authors attempt to critically review the existing literature and provide practical advice on these issues.

[Infections]

The individual risk assessment concerning infections in patients with rheumatic diseases is based on the detailed personalized documentation of relevant risk factors, such as the underlying disease itself, the intensity of immunosuppressive therapy and the severity of any comorbidities. From the perspective of infectiology, the history of repeated and severe infections as well as previous illnesses, such as (latent) tuberculosis and chronic hepatitis B or C need to be considered. In some instances prophylactic antibiotic therapy might be required, which should otherwise be avoided in order to prevent selection of resistant pathogens. Furthermore, vaccinations are particularly suitable to specifically minimize the risk for frequent infectious diseases.

Reactivation of hepatitis B virus infection following rituximab treatment in HBsAg-negative, HBcAb-positive rheumatoid arthritis patients: A long-term, real-world observation

AIM

Longitudinal data of the reactivation of hepatitis B virus (rHBV) and serial serological markers or HBV-DNA has been limited. This study aimed to investigate the temporal course of rHBV development in rheumatoid arthritis (RA) patients undergoing long-term rituximab therapy.

METHODS

The occurrence of rHBV was examined in 157 RA patients during rituximab therapy. Serum levels of HBV surface antigen (HBsAg), HBV core antibody (HBcAb), and HBsAb were determined by electrochemiluminescence immunoassays, and viral loads by real-time polymerase chain reaction assay.

RESULTS

Among 157 patients undergoing rituximab therapy, 103 (65.6%) were HBsAg-negative and HBcAb-positive. Before rituximab therapy, 20 (19.4%) of these 103 patients were HBsAb-negative, while 83 (80.1%) were HBsAb-positive. Five (20%) HBsAb-negative patients developed rHBV after rituximab therapy. Among 83 HBsAb-positive patients, 4 (4.8%) developed rHBV. Among 9 patients with rHBV, 7 (77.7%) exhibited HBsAg seroreversion. Significant decline of HBsAb titers (mean ± SD, 296.0 ± 417.3 mIU/mL at baseline vs 187.0 ± 332.5 mIU/mL after rituximab therapy, P < 0.001) was observed in HBsAg-/HBsAb + patients. All HBsAg-negative patients who developed rHBV during rituximab therapy were characterized by baseline HBsAb titers < 100 mIU/mL and negative HBsAb at the time of rHBV. HBsAb positivity was an independent protective factor for rHBV (hazards ratio: 0.14, 95% CI: 0.03-0.62, P = 0.009).

CONCLUSION

Baseline HBsAb positivity was a significant protective factor for rHBV in HBsAg-negative, HBcAb-positive RA patients receiving rituximab therapy.

Considering hepatitis C virus infection as a systemic disease

Hepatitis C virus (HCV) infection has been demonstrated to result in several adverse hepatic outcomes and has been associated with a number of important extrahepatic manifestations. The scope of extrahepatic clinical possibilities includes systemic diseases such as vasculitis and lymphoproliferative disorders, cardiovascular disease, myalgia, arthritis, and sicca syndrome. These end-organ effects of HCV may dominate the clinical course beyond the hepatic complications and significantly worsen the long-term prognosis of infected patients. Until several years ago, the standard of care for the treatment of HCV infection had been interferon-alpha-based regimens, which not only had limited effectiveness in achieving a cure but were often poorly tolerated, especially in patients with kidney disease. In those HCV-infected patients with significant systemic manifestations, the interferon-based regimens were problematic given their association with a wide variety of toxicities. The development of highly effective direct-acting antiviral agents to treat HCV infection presented an opportunity to improve the HCV care cascade with the eradication of HCV in most infected patients and by reducing the burden of both hepatic and extrahepatic complications.

Clinical connection between rheumatoid arthritis and liver damage

When liver damage is present in rheumatoid arthritis (RA) patients, it is sometimes difficult to determine whether it is a hepatic manifestation of RA, associated primary liver disease or hepatotoxic liver disease which developed during the treatment of RA. Liver damage during RA is most common in the form of asymptomatic abnormal liver tests. Occasionally, liver damage may progress to cirrhosis. Patients with RA are more susceptible to an associated autoimmune liver disease. Medications used in rheumatology are often hepatotoxic and it is difficult to differentiate between hepatic manifestations of the primary disease and potential hepatotoxicity of the administered medications. The significance of the paper is in the fact that it includes the most relevant and the latest information on this commonly present problem in clinical practice. The aim of the author is to provide comprehensive but at the same time concise data which will be useful to the doctors who come into contact with RA patients with symptomatic or asymptomatic liver disease. Timely diagnosis and treatment of liver disease in RA patients can significantly influence the course and outcome of rheumatoid arthritis.

Avoidance of Harm From Treatment for ANCA-Associated Vasculitis

Purpose of review With established immunosuppressant treatment regimens for anti-neutrophil cytoplasm antibody-associated vasculitides (AAV), prognosis has significantly improved. The mainstay of treatment still comprises high-dose corticosteroids and cyclophosphamide for severe forms, although rituximab is being increasingly utilised instead of cyclophosphamide as induction therapy. AAV patients experience an excess of infections, malignancies and cardiovascular events as compared to the general population, which is a combination of the systemic inflammatory process associated with vasculitis and the adverse events from treatment.

Recent findings Successful therapy should focus on suppressing disease activity and minimising treatment-related toxicity. Infection is the largest contributor to morbidity and mortality in the first year of treatment, and annual pneumococcal and influenza vaccinations, Pneumocystis jiroveci prophylaxis and tuberculosis (TB) and Hepatitis B virus screening are advised. Patients on high-dose corticosteroid treatment should have regular blood sugar monitoring, a FRAX assessment with vitamin D and calcium supplementation, consideration of prophylaxis for gastric ulcers and a cardiovascular risk assessment. Patients who are treated with cyclophosphamide could also receive MESNA to reduce the risk of chemical cystitis. Cyclophosphamide, methotrexate and azathioprine all require blood monitoring schedules due to the risk of bone marrow suppression, liver and renal toxicity. Hypogammaglobulinaemia is a recognised risk of rituximab treatment. Patients of reproductive age need to be counselled on the infertility risks with cyclophosphamide and the teratogenicity associated with it, methotrexate and mycophenolate mofetil.

Summary A greater focus on identifying clinical and biological markers that will help identify those patients at greatest risk of relapse, e.g. GPA and PR3-ANCA specificity, from those patients at greatest risk of toxicity, e.g. increasing age and declining GFR, is required to allow treatment to be tailored accordingly.

Safety of Abatacept in Rheumatoid Arthritis With Serologic Evidence of Past or Present Hepatitis B Virus Infection

OBJECTIVE

Rheumatoid arthritis (RA) with concomitant hepatitis B virus (HBV) infection represents a therapeutic challenge due to the risk of HBV reactivation under immunosuppressive treatment. To date there are few data coming from anecdotal case reports that concern HBV reactivation following treatment with abatacept. This observational retrospective study was aimed to assess the safety profile of abatacept in this particular clinical setting.

METHODS

Eleven Italian rheumatologic centers provided data from patients with RA and positive HBV serology treated with intravenous abatacept. HBV markers and clinical and laboratory data were checked at followup visits every 3 months.

RESULTS

In total, 72 patients were included in the study: 47 inactive carriers, 21 occult carriers, and 4 chronic active carriers for HBV. At baseline all of the patients had normal liver function tests and low or undetectable HBV DNA levels, except for those with chronic active hepatitis. Thirteen patients received prophylaxis with lamivudine, and 4 received treatment with adefovir or tenofovir. At the end of the 24-month followup period, 49 patients were being treated. Data from 316 followup visits showed that abatacept was safe. No patients experienced reactivation of hepatitis B. Treatment withdrawals (23 patients) were due to lack of efficacy, subject decision/lost at followup, or adverse events not related to HBV infection.

CONCLUSION

Our study provides reassuring data about the safety profile of abatacept in RA with concomitant HBV infection without universal antiviral prophylaxis. Further prospective studies are needed to confirm these preliminary results.

Infectious complications of a rituximab-based immunosuppressive regimen in patients with glomerular disease

BACKGROUND

Recent years have seen increasing use of rituximab (RTX) for various types of primary and secondary glomerulopathies. However, there are no studies that specifically address the risk of infection related to this agent in patients with these conditions.

METHODS

We reviewed the outcomes of all patients who received RTX therapy for glomerular disease between June 2000 and October 2011 in eight French nephrology departments. Each case was analysed for survival, cause of death if a non-survivor and/or the presence of infectious complications, including severe or opportunistic infection occurring within the 12 months following RTX infusion.

RESULTS

Among 98 patients treated with RTX, 25 presented with at least one infection. We report an infection rate of 21.6 per 100 patient-years. Five patients died within 12 months following an RTX infusion, of whom four also presented with an infection. The median interval between the last RTX infusion and the first infectious episode was 2.1 months (interquartile range 0.5-5.1). Most infections were bacterial (79%) and pneumonia was the most frequent infection reported (27%). The presence of diabetes mellitus (P = 0.006), the cumulative RTX dose (P = 0.01) and the concomitant use of azathioprine (P = 0.03) were identified as independent risk factors. Renal failure was significantly associated with an increased infection risk by bivariate analysis (P = 0.03) and was almost significant by multivariate analysis (P = 0.05). Nephrotic syndrome did not further increase the risk of infection and/or death.

CONCLUSION

The risk of infection after RTX-based immunosuppression among patients with glomerulopathy must be considered and patients should receive close monitoring and appropriate infection prophylaxis, especially in those with diabetes and high-dose RTX regimens.

Hepatitis B Reactivation in Rheumatic Diseases: Screening and Prevention

Hepatitis B virus (HBV) reactivation (HBVr) has been an increasingly recognized and appreciated risk of immunosuppressive therapies in rheumatic patients. Despite its potential for significant morbidity and mortality, HBVr is a fully preventable complication with appropriate pretreatment screening and close monitoring of susceptible patients. Better knowledge of the risk for HBVr with the different antirheumatic agents and the establishment of the new-generation oral antivirals in clinical practice has greatly improved the design of screening and therapeutic algorithms. In this review, all available data regarding HBVr in rheumatic patients are critically presented and a screening and therapeutic algorithm is proposed.

New insights into HCV-related rheumatologic disorders: A review

Hepatitis C virus (HCV) infected patients are known to be exposed to major liver complications i.e. cirrhosis and hepatocellular carcinoma. In addition, many extrahepatic manifestations including rheumatologic disorders have been reported in up to two-third of HCV infected patients. These manifestations include frank auto-immune and rheumatic diseases (such as arthralgia, myalgia, arthritis, sicca syndrome and vasculitis) which may dominate the course of infection. Until recently, the standard of care of HCV has been the use of interferon-alpha based regimens, which not only had limited effectiveness in HCV cure but were poorly tolerated. In patients with rheumatic diseases interferon-based regimens may be problematic given their association with a wide variety of autoimmune toxicities. Recent therapeutic advances with new direct anti-HCV therapies (interferon-free) which are more effective and better tolerated, make screening for this comorbidity in patients with rheumatic disorders more important than ever. This review aimed to outline main HCV extrahepatic with a special focus on rheumatologic manifestations.

Hepatitis C Therapy in Renal Patients: Who, How, When?

Renal patients are overexposed to hepatitis C virus (HCV) infection. Hepatitis C virus infection may induce renal disease, i.e., cryoglobulinemic membrano-proliferative glomerulopathy and non-cryoglobulinemic nephropathy. Hepatitis C virus impacts general outcomes in chronic kidney disease, dialysis or transplanted patients. Hepatitis C virus infection is now about to be only part of their medical history thanks to new direct acting antiviral drugs exhibiting as much as over 95% of sustained virological response. All HCV-infected patients potentially can receive the treatment. Control of the virus is associated with better outcomes in all cases, whatever the severity of the hepatic or renal disease. This article focuses on HCV-induced renal diseases, the reciprocal impact of HCV infection on the renal outcome and renal status in liver disease, use of new direct-acting antiviral drugs with dosage adaptations and the most recent safety data.

Reactivation of occult hepatitis B virus infection in patients with rheumatic diseases: pathogenesis, risk assessment and prevention

Over the past decade, reactivation of occult hepatitis B virus (HBV) infection has garnered much attention from rheumatologists owing to a number of reports which have indicated the potential risk of biologics in causing this previously ignored infectious complication. Hepatitis due to reactivation of occult HBV infection occurs only occasionally but with high mortality upon occurrence, placing us in a clinical dilemma "to address or not to address?" In this review, we discuss how biological and other immunosuppressive therapies increase the risk of developing reactivation of occult HBV infection and attempt to solve this clinical quandary.

Safety of biologic and nonbiologic disease-modifying antirheumatic drug therapy in veterans with rheumatoid arthritis and hepatitis B virus infection: a retrospective cohort study

Introduction

We evaluated the safety of current treatment regimens for patients with RA and HBV in a large US cohort.

Methods

We identified biologic and nonbiologic treatment episodes of RA patients using 1997 to 2011 national data from the US Veterans Health Administration. Eligible episodes had evidence of HBV infection (HBV surface antigen, HBV core antibody, HBV e-antibody and/or HBV DNA) and had a baseline alanine aminotransferase (ALT) <1.5 times the upper limit of laboratory normal within 90 days prior to initiation of a new biologic or nonbiologic DMARD. The main outcome of interest was hepatotoxicity, defined as ALT elevation >100 IU/mL. Results were reported as the cumulative incidence of treatment episodes achieving hepatotoxicity at 3, 6 and 12 months post biologic exposure.

Results

Five hundred sixty-six unique RA patients with HBV contributed 959 treatment episodes. Mean age was 62.1 ± 10.3 years; 91.8% were male. Hepatotoxicity was uncommon, with 26 events identified among 959 episodes (2.7%) within 12 months. Hepatotoxicity was comparable between biologic and nonbiologic DMARDs (2.6% vs. 2.8%, P = 0.87). The median time between HBV screening and starting a new RA drug was 504 days (IQR 144, 1,163). Follow-up HBV testing occurred among 14 hepatotoxicity episodes (53.8%) at a median of 202 days (IQR 82, 716) from the date of ALT elevation. A total of 146 (15.2%) treatment episodes received at least one test for HBV DNA at any point in the observation period.

Conclusions

Among US veterans with RA and HBV the risk of hepatotoxicity is low (2.7%), and comparable between biologic and nonbiologic DMARDS (2.8% vs. 2.6%, P = 0.87). HBV testing associated with DMARD initiation or hepatotoxicity was infrequent.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0628-z) contains supplementary material, which is available to authorized users.

Risk of hepatitis B virus reactivation in rheumatoid arthritis patients undergoing biologic treatment: Extending perspective from old to newer drugs

Hepatitis B virus (HBV) reactivation in rheumatoid arthritis (RA) patients undergoing biological therapy is not infrequent. This condition can occur in patients with chronic hepatitis B as well as in patients with resolved HBV infection. Current recommendations are mainly focused on prevention and management strategies of viral reactivation under tumor necrosis factor-α inhibitors or chimeric monoclonal antibody rituximab. In recent years, growing data concerning HBV reactivation in RA patients treated with newer biological drugs like tocilizumab and abatacept have cumulated. In this review, epidemiology, pathogenesis and natural history of HBV infection have been revised first, mainly focusing on the role that specific therapeutic targets of current biotechnological drugs play in HBV pathobiology; finally we have summarized current evidences from scientific literature, including either observational studies and case reports as well, concerning HBV reactivation under different classes of biological drugs in RA patients. Taking all these evidences into account, some practical guidelines for screening, vaccination, prophylaxis and treatment of HBV reactivation have been proposed.

Frequency, risk factors and prophylaxis of infection in ANCA-associated vasculitis

BACKGROUND

Antineutrophil cytoplasm antibody (ANCA)-associated vasculitides are potentially life-threatening disorders.

MATERIALS AND METHODS

Even though immunosuppressive therapy improves the prognosis, adverse events, either attributable to persistent disease activity or side effects of treatment remain a challenge. Infectious complications are the leading cause of death in the first year after diagnosis and a major cause of morbidity and mortality thereafter.

RESULTS

Their incidence in clinical trials varies considerably but opportunistic and life-threatening infections, such as Pneumocystis jirovecii pneumonia or systemic cytomegalovirus infections, are frequent and thus predisposing/risk factors need to be defined. Pneumocystis jirovecii pneumonia has been associated with a lymphocyte count below 300/mm(3) . Additionally, besides the aggressiveness of the immunosuppressive regimen administered (especially the cumulative dose of steroids and cyclophosphamide), an elevated serum creatinine or dialysis dependency, older age and pulmonary involvement increase the rate of infectious complications.

CONCLUSIONS

We suggest to routinely prescribe trimethoprim-sulfamethoxazole or antimicrobial agents such as pentamidine in case of intolerance or contraindication in the early phase of induction therapy irrespective of the immunosuppressive strategy used and to continue therapy, together with other targeted measures (antiviral, antimycotic or antibiotic) in the presence of risk factors for a prolonged period of time. Finally, there is an urgent need to standardize the reporting of infectious complications in clinical trials to enable comparing the adverse event spectrum of distinct treatment approaches more appropriately.

Extrahepatic manifestations of chronic hepatitis C virus infection

Hepatitis C virus (HCV) infected patients are known to be at risk of developing liver complications i.e. cirrhosis and liver cancer. However, the risks of morbidity and mortality are underestimated because they do not take into account non-liver consequences of chronic hepatitis C virus infection. Numerous extrahepatic manifestations have been reported in up to 74% of patients, from perceived to disabling conditions. The majority of data concern hepatitis C virus-related autoimmune and/or lymphoproliferative disorders, from mixed cryoglobulinaemia vasculitis to frank lymphomas. More recently, other hepatitis C virus-associated disorders have been reported including cardiovascular, renal, metabolic, and central nervous system diseases. This review aims to outline most of the extrahepatic manifestations that are currently being investigated, including some of autoimmune and/or lymphoproliferative nature, and others in which the role of immune mechanisms appears less clear. Beyond the liver, hepatitis C virus chronic infection should be analyzed as a multifaceted systemic disease leading to heavy direct and indirect costs. The accurate consideration of extrahepatic consequences of such a systemic infection significantly increases the weight of its pathological burden. The need for effective viral eradication measures is underlined.

Computerized physician order entry-based system to prevent HBV reactivation in patients treated with biologic agents: the PRESCRIB project

Computerized physician order entry (CPOE) applications are widely used to prevent medical errors. In our center, a CPOE system has been in use since 2009 on both the inpatient and outpatient levels. A new and simple alert was introduced in the CPOE system to notify healthcare providers of the potential risk of viral reactivation when prescribing biological therapies, thereby facilitating the request for a serological profile (hepatitis B surface antigen [HBsAg], anti-HBc, and anti-HBs) in patients who have not had these tests. Between May 2012 and May 2013, a total of 1,076 patients undergoing biological treatment were included in the implementation of the CPOE in our hospital, resulting in the identification of 4 HBsAg-positive and 69 anti-HBc-positive/HBsAg-negative patients, two of them with positive viral loads. Since the implementation of this alert system, over 90% of patients who were prescribed a biological drug (BD) have undergone serological screening to detect hepatitis B virus (HBV) infection. The use of the alert system has increased the screening rate from less than 50% to 94% for HBsAg and from less than 30% to 85% for anti-HBc in patients for whom a BD is prescribed. Six patients received prophylactic antiviral therapy. No patient had HBV reactivation.

CONCLUSION

This study demonstrates the feasibility of implementing a CPOE system that has allowed our hospital to increase the rate of HBV screening. Its use has facilitated the identification of patients at high risk for HBV reactivation and permitted physicians to prescribe prophylactic measures according to current guidelines.

Immunosuppression in Patients with Chronic Hepatitis B

After hepatitis B virus (HBV) infection, HBV DNA persists in minute amounts in hepatocyte nuclei even in individuals with “resolved” infection. Viral replication and development of liver disease depend on the balance between viral mechanisms promoting persistence and host immune control. Patients with active or inactive disease or resolved HBV infection are at risk for reactivation with immunosuppressive therapy use. HBV reactivation varies from a clinically asymptomatic condition to one associated with acute liver failure and death. We review recent studies on HBV reactivation during immunomodulatory therapies for oncologic, gastroenterological, rheumatic, and dermatologic disorders. Risk calculation should be determined through HBV screening and assessment of immunosuppressive therapy potency. We also discuss monitoring for reactivation, prophylactic antiviral therapy, and treatment of reactivation. Prophylactic antiviral treatment is needed for all HBsAg carriers and selected patients who have anti-HBc without HBsAg and is critical for preventing viral reactivation and improving outcomes.

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.

Systemic diseases and biotherapies: understanding, evaluating, and preventing the risk of hepatitis B reactivation

Hepatitis B virus (HBV) reactivation can occur in chronic carriers of the HBV surface antigen (HBsAg) and constitutes a well-known complication of immunosuppressive therapy. HBV reactivation has also been reported after contact with the HBV. The increasing use of biological agents (TNFα antagonists, rituximab, abatacept, and tocilizumab) to treat systemic diseases has resulted in numerous publications about the risk of HBV reactivation. The relevant scientific societies have issued recommendations designed to prevent HBV reactivation. The main measures consist of screening for markers indicating chronic HBV infection (HBsAg) or HBV infection in the distant past (antibodies to the HBV core antigen) before initiating biological therapies, vaccinating marker-negative patients, and considering close follow-up or antiviral treatment before immunosuppressive treatment initiation or in the event of HBV reactivation. Here, we discuss the pathophysiological mechanisms underlying HBV reactivation during biological treatments, most notably in patients with occult HBV infection or markers for remote HBV infection, whose hepatocyte nuclei may contain a resistance form of HBV DNA known as covalently closed circular DNA (cccDNA). Assessment of the risk of reactivation relies on the HBV status, drugs used, and data from the literature. Finally, we discuss the various recommendations and modalities for HBV vaccination, preemptive treatment, and patient management, according to the level of risk and to the circumstances in which reactivation occurs.