Progressive Disappearance of Anti-Hepatitis B Surface Antigen Antibody and Reverse Seroconversion after Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Previous Hepatitis B Virus Infection

Management of viral hepatitis in hematologic malignancies

Viral hepatitis is the third major cause of liver dysfunction in allogeneic transplant recipients and has become a significant concern in patients with hematological malignancies receiving chemotherapy. Thus, identification of patients at risk for viral hepatitis is very important when evaluating and treating hematological malignancies. Serologic screening for all patients should include anti-HCV, hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) testing. Current therapies for hepatitis B (HBV) virus infection are aimed at viral suppression, while treatment for hepatitis C (HCV) virus can eradicate infection in many treated patients. To prevent HBV viral reactivation, prophylaxis with nucleoside analogues should be initiated for all HBsAg-positive patients. HCV infection appears to have little impact on short-term survival after bone marrow transplantation (BMT), but eventually can impact long-term survival due to progression of liver disease. In this review we will highlight the mechanisms of virus reactivation, clinical manifestations, and management strategies to minimize acute and chronic morbidity in this population.

Hepatitis B virus reactivation following immunosuppressive therapy: guidelines for prevention and management

It is well known that immunosuppressive drugs or cancer chemotherapy can stimulate replication of hepatitis B virus (HBV) and precipitate severe flares of HBV infection. The risk of this syndrome of 'reactivation hepatitis B' is highest in haematopoietic stem cell or solid organ transplant recipients and in those undergoing chemotherapy for haematological malignancies; however, it has been described following almost any form of immunosuppressive treatment. Fortunately, it can be largely prevented by prophylactic therapy with oral anti-HBV nucleoside/nucleotide analogues. Importantly, chronic HBV infection is usually asymptomatic, and most patients at risk are likely to be unaware that they carry the infection. Thus, the key to avoiding this potentially fatal complication of immunosuppressive treatment is to ensure that all patients at risk of chronic HBV infection are screened for the disease before commencing immunosuppressive treatment or chemotherapy.

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.

Allografted Recipients Immunized Against Hepatitis B Virus are at High Risk of Gradual Surface Antibody (HbsAb) Disappearance Post Transplant, Regardless of Adoptive Immunity Transfer

Immunized against hepatitis B virus (HBV) recipients are at risk of developing HBV postallogeneic stem cell transplantation because of the potential loss of their HBV immunity. The aim of the study was to evaluate: (1) the HbsAb eradication incidence posttransplant and potential risk factors, (2) the impact of donor's immunity on HbsAb loss, (3) the incidence of hepatitis B in patients with HbsAb disappearance. We studied, retrospectively, in 26 vaccinated and 56 naturally immunized recipients, the posttransplant HbsAb titers for a median period of 36 (6-132) months. The probability of HbsAb loss and HBV-related hepatitis was determined in all recipients. The impact of donor's immunity origin in the HBsAb disappearance was evaluated in the subgroup of, actively or naturally, immunized recipients/donors pairs. The 5-year probability of HbsAb disappearance was 90% for all patients with 18% probability of developing hepatitis at 12 years, for those who lost HbsAb. Marrow graft, antithymocyte globulin administration, age<30 years and chronic graft-versus-host disease were significant risk factors for HbsAb loss. In the subgroup of immunized recipients/donors, the donor's active immunization significantly affected this loss. Allotransplanted patients are at high risk of losing protection against HBV. The adoptive transfer of active HBV immunity does not seem to offer sustained protection posttransplant.

Long-term surveillance of haematopoietic stem cell recipients with resolved hepatitis B: high risk of viral reactivation even in a recipient with a vaccinated donor

Reactivation of resolved hepatitis B virus (HBV) infection is increasingly recognized in patients with severe immunosuppression. We monitored seven patients with pretransplant antibodies to hepatitis B surface antigen (anti-HBs) and hepatitis B core antigen (anti-HBc) for HBV reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Reverse seroconversion (from anti-HBs to HBsAg) was observed in six recipients occurring 12, 14, 16, 22, 31 and 39 months after allo-HSCT, respectively. The only patient without HBV reactivation had the highest pretransplant anti-HBs titre and died after the shortest follow-up period (25 months). A novel HBV surface mutant (D144G/G145E) was isolated from one recipient of stem cells from a donor vaccinated against HBV. Another surface mutant (P142L/G145R) was detected in a recipient from a non-immune donor. Serum ALT elevation was measured in only two of the six patients with viral reactivation, followed by spontaneous clearance of HBsAg in one of them. Antiviral treatment reduced viral load in five patients, but the emergence of YMDD motif polymerase mutations resulted in lamivudine resistance in two patients. In conclusion, the risk of reactivation of a resolved HBV infection is close to 100% in allogeneic stem cell recipients and vaccination of the donor does not always warrant reliable protection.

Risk assessment in haematopoietic stem cell transplantation: The liver as a risk factor

Patients with liver dysfunction have an increased risk of developing early and late complications after haematopoietic stem-cell transplantation (HSCT). That's why it is mandatory to evaluate liver status before transplantation in all cases. This evaluation should allow us to decide whether HSCT can be performed or whether we should adopt measures focused on preventing these complications. The evaluation of the liver in an HSCT candidate requires the collection of information by history-taking, physical examination, liver-function tests and, occasionally, imaging tests and liver biopsy. Additionally, as infection by hepatitis B or C viruses represents the most relevant cause of hepatic dysfunction after HSCT, the serological status of the patient should be carefully evaluated. This chapter tries to analyse and systematise the most important aspects in the patient's evaluation. Finally, as some liver dysfunctions in the stem-cell donor can have a negative impact for the donor during the harvest and/or for the recipient during HSCT, the methodology to evaluate the donors will also be analysed.

[Autoimmune thrombopenia associated with hepatitis B reactivation (reverse seroconversion) after autologous hematopoietic stem cell transplantation]

We report a case of autoimmune thrombocytopenia associated with acute reverse seroconversion of hepatitis B in a patient who was initially hepatitis B virus surface antigen negative and hepatitis B virus surface antibody positive. Reactivation occurred 9 months after chemotherapy with anti-CD 20 monoclonal antibodies and autologous hematopoietic stem cell transplantation for lymphoma had been performed. After non specific polyglobulin injections and treatment with adefovir dipivoxil, thrombocytopenia and viral replication were controlled. Seroconversion for both HBe and HBs occurred at 5 months. Adefovir was stopped 4 months later with no relapse during fifteen months of follow-up. This case shows that patients who have had previous contact with hepatitis B virus should be monitored if they become immunosuppressed, even if anti-HBs were initially present.

Changes in Serologic Markers of Hepatitis B Following Autologous Hematopoietic Stem Cell Transplantation

Korea is an endemic area for hepatitis B virus (HBV) infection. Reactivation of HBV is a well-recognized complication in patients with chronic HBV infection undergoing cytotoxic or immunosuppressive therapy, and there are some reports of hepatitis B reverse seroconversion after HSCT. This study evaluated changes in HBV serology after HSCT. We reviewed the medical records of 141 patients who had available HBV serologic data after autologous HSCT. Patient information was retrospectively collected from the BMT database. Before transplantation, 12 patients were positive for hepatitis B surface antigen (HBsAg) and received lamivudine prophylaxis. There was 1 case of reactivation of HBV among these patients. One hundred twenty-nine patients were negative for HBsAg before HSCT, of whom 110 were positive and 19 were negative for hepatitis B surface antibody (anti-HBs). Sixty-two of the 110 patients who were positive for anti-HBs were also positive for hepatitis B core antibody (anti-HBc). Eight patients were negative for anti-HBs and anti-HBc. Seven patients who were initially negative for HBsAg were identified as positive after HSCT, and 5 of those 7 patients developed acute hepatitis, thus indicating reverse seroconversion. Univariate analysis showed that reverse seroconversions were observed more frequently with multiple myeloma than another disease (P = .005; relative risk, 11.854; 95% confidence interval, 1.381-101.770). Other factors, such as age, sex, and presence of HBcAb before HSCT, had no statistically significant affect on reverse seroconversion. In conclusion, reverse seroconversion of HBV is not a rare complication of autologous HSCT, and the risk of reverse seroconversion after treatment is a serious concern due to possible complications arising from patients' suppressed immune systems.

Screening, prevention and treatment of viral hepatitis B reactivation in patients with haematological malignancies

The prevalence of hepatitis B virus (HBV) infection in patients with haematological malignancies is increased compared with the general population worldwide. HBV reactivation is common following chemotherapy and is associated with a high mortality despite prompt anti-viral treatment. HBV reactivation may necessitate interruption of chemotherapy with adverse prognostic consequences for the haematological disease. Chemotherapy-induced immune suppression may lead to increased HBV replication. Immune reconstitution within the weeks and months following recovery from chemotherapy may be associated with a flare of hepatitis B manifested by hepatocellular injury. Risk factors associated with HBV reactivation include detectable hepatitis B surface antigen (HBsAg), HBV DNA, Hepatitis B e (HBeAg) antigen, antibodies to hepatitis B core antigen (anti-HBc), treatment with corticosteroids, young age and male gender. Lamivudine is effective during HBV reactivation due to immune suppression. Clinical trials have demonstrated that pre-emptive antiviral treatment with lamivudine is superior to deferred treatment. Current recommendations emphasise screening for HBV infection in all haematology patients, particularly prior to chemotherapy. Patients who are HBsAg positive or HBV DNA positive should receive pre-emptive treatment with lamivudine before chemotherapy. The duration of lamivudine treatment may be prolonged commensurate with the degree of immunosuppression. HBV naïve patients should be immunised against hepatitis B, as should haematopoietic stem cell donors. In summary, overt and occult HBV pose a serious, but preventable, threat. Pre-treatment screening of patients at risk should be practiced diligently by all clinicians that treat patients with malignancies.

Occult hepatitis B virus infection

The persistence of hepatitis B virus (HBV) genomes in HBV surface antigen (HBsAg) negative individuals is termed occult HBV infection. Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays, but more frequently it is due to a strong suppression of viral replication and gene expression. Occult HBV infection is an entity with world-wide diffusion, although the available data of prevalence in various categories of individuals are often contrasting because of the different sensitivity and specificity of the methods used for its detection in many studies. Occult HBV may impact in several different clinical contexts, including the transmission of the infection by blood transfusion or organ transplantation and its acute reactivation when an immunosuppressive status occurs. Moreover, much evidence suggests that it can favour the progression of liver fibrosis and above all the development of hepatocellular carcinoma.

Reactivation of an occult hepatitis B virus escape mutant in an anti-HBs positive, anti-HBc negative lymphoma patient

BACKGROUND

Hepatitis B virus (HBV) often persists after resolution, but its replication is suppressed by antiviral T cells. Immunosuppressive treatment may lead to viral reactivation and severe hepatitis. Early antiviral therapy prevents reactivation but some occult HBV infections are not easily detectable.

RESULTS

Here we describe a patient with a progressive non-Hodgkin lymphoma who had probably not been vaccinated against HBV and, before immunosuppression, showed antibodies (anti-HBs) against the viral surface antigen (HBsAg) as the only possible marker of occult HBV infection. Under immunosuppression he developed viremia (>10(8)copies/mL). The virus exhibited three S gene mutations (L109R, C137W, G145R) which led to false negative HBsAg results and diminished binding of vaccine-induced anti-HBs.

CONCLUSIONS

Reliable screening and monitoring of severely immunosuppressed patients for HBV should include, in addition to anti-HBc and HBsAg, anti-HBs and sensitive HBV DNA assays. Furthermore, active vaccination or hepatitis B immune globulin may not protect against such mutants.

Hepatitis B virus reactivation in patients receiving chemotherapy for malignancies: role of precore stop-codon and basic core promoter mutations

Hepatitis B virus (HBV) strains carrying the precore stop-codon mutation (A1896) have been considered among the predisposing factors for reactivation during chemotherapy for malignancies. The role of the T1762/A1764 basic core promoter (BCP) mutations has not been fully evaluated. We aimed to record any changes in HBV serological markers after reactivation, detect the presence of A1896 and BCP mutations and evaluate the type of cytotoxic drugs involved. We retrospectively screened eight patients presenting with HBV reactivation following chemotherapy for malignancies. The chemotherapy regimens used included corticosteroids (CSs), fludarabine and cyclophosphamide/adriamycine. The INNO-LiPA HBV PreCore kit was used for the detection of the A1896 and BCP mutations. Six patients who were hepatitis B surface antigen (HBsAg)-(+)/hepatitis B e antigen (HBeAg)-(-) before chemotherapy, had disease reactivation following a mean of four cycles of chemotherapy. Four survived and two died of hepatic failure. At the time of reactivation, all six patients carried the A1896 and five of them the BCP mutations. The remaining two patients were HBsAg-(-)/anti-HBs-(+)/anti-hepatitis B core (HBc)-(+)/HBeAg-(-) before chemotherapy. One of them reverted to HBeAg-(+) status but remained HBsAg-(-), while the other became HBsAg-(+)/HBeAg-(+), following three and eight cycles of fludarabine treatment, respectively. The former carried the A1896 and the latter the wild-type virus. Both died from causes associated with their haematological disease. All but one of our patients with HBV reactivation during chemotherapy carried the precore stop-codon and BCP mutations. Whether this occurs more frequently in such patients than those carrying the wild-type virus needs further investigation. Fludarabine should be added to the list of drugs inducing HBV reactivation. HBV reactivation following fludarabine treatment occurred in HBsAg-(-) patients who had been anti-HBs-(+).

Reactivation of Hepatitis B Infection following Allogeneic Bone Marrow Transplantation in a Hepatitis B-Immune Patient: Case Report and Review of the Literature

BACKGROUND

Reactivation of hepatitis B virus (HBV) infection following allogeneic bone marrow transplantation is a rare phenomenon.

METHODS

Reverse seroconversion, defined as the clearance of antibody to hepatitis B surface antigen (HBsAb) and the appearance of hepatitis B surface antigen (HBsAg) in a patient with resolved HBV infection (i.e., a HBsAg-negative, HBsAb-positive, hepatitis B core antibody-positive patient) following receipt of a bone marrow transplant is described. A review of related cases in the literature was undertaken to identify clinical features associated with this phenomenon.

RESULTS

We present a case of reactivation of HBV infection in a 47-year-old man after receipt of an allogeneic bone marrow transplant for acute myelogenous leukemia. Before undergoing bone marrow transplantation, the presence of HBsAb and hepatitis B core antibody and the absence of HBsAg indicated clearance of natural HBV infection. The donor was HBsAg and HBsAb negative. Twenty-nine months after bone marrow transplantation, the patient developed transaminitis and evidence of active HBV infection (the patient had test results positive for HBsAg, negative for HBsAb, and positive for HBV DNA). A total of 28 other cases of reverse seroconversion have been described in the literature, 11 of which provided adequate information to be summarized in detail together with the present case. Reactivation of HBV infection following bone marrow transplantation appears to occur almost exclusively in patients who have received marrow from an HBsAb-negative donor and have experienced graft-versus-host disease, the onset of which is associated with tapering of immunosuppressive therapy.

CONCLUSIONS

Although HBV reverse seroconversion is an uncommon event, understanding the clinical features associated with the development of HBV reverse seroconversion may provide insight into how such a potentially fatal complication may be avoided.