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

Adoptive immune transfer from donors offers Anti-HBV protection to HBsAb-negative patients after Allo-HSCT

Adoptive transfer of hepatitis B virus (HBV) immunity may occur following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Here, we investigated the adoptive transfer of HBV immunity in 112 patients without HBV surface antibody (HBsAb) (HBsAb-) at the time of their first allo-HSCT. After allo-HSCT, HBV-DNA（87.5%） and HBsAg（11.1%%）cleared in HBsAg+ patients. All HBsAg- patients acquired HBsAb immediately. Nevertheless, HBsAb titers subsequently declined, and 39/67 (58.2%) patients lost HBsAb during follow-up. The 5-year overall survival (OS) was better in patients who lost HBsAb. Multivariate analysis showed that the independent risk factors for OS were lack of cytomegalovirus (CMV) clearance, acute graft-versus-host disease (aGVHD), and no HBsAb loss. Overall, adoptive immune transfer offers anti-HBV protection to patients without HBsAb, as they acquire HBsAb and clear HBV-DNA and HBsAg, while HBsAb loss after allo-HSCT predicts better survival.

Immune Status Against Hepatitis B in Patients After Allogeneic Hematopoietic Cell Transplantation-Factors Affecting Early and Long-Lasting Maintenance of Protective Anti-HBs Titers

The immunization of allogeneic hematopoietic cell transplantation (HCT) recipients against vaccine-preventable diseases is a part of posttransplantation guidelines. We conducted a prospective study to assess clinical and immunological parameters that would determine the response and long-term maintenance of protective antibody titers upon the hepatitis B virus (HBV) vaccination after HCT. The investigated variables included: vaccination of the HCT recipients and their donors prior to HCT, chronic graft versus host disease (cGVHD) and the timing of post-HCT vaccination, and B- and T-cell subtype status. Forty-two patients were immunized with three or more doses of recombinant hepatitis B surface antigen (rHBsAg) administered according to the individualized schedule of 0-1-2-6-(12) months. After vaccination, seroconversion was achieved in the whole group. The vaccines were categorized according to the antibody (Ab) titers as weak (WRs; 28.7%), good (GRs; 38%) or very good responders (VGRs; 3.3%). In multivariate logistic regression, severe cGVHD (OR= 15.5), and preceding donor immunization (OR= 0.13) were independent predictors of a weak response to vaccination. A prior belonging to the WR group impaired the durability of protection (OR= 0.17) at a median follow-up of 11.5 years. Patients with severe cGVHD showed a trend toward lower median Ab titers, although they required a higher rate of booster vaccine doses. All VGRs had CD4+ cells > 0.2 x 10⁶/L. There was a lower mean rate of CD4+IL2+ lymphocytes in WRs. Vaccination demonstrated the immunomodulatory effect on B-cell and T-cell subsets and a Th1/Th2 cytokine profile, while shifts depended on a history of severe cGVHD and the type of vaccine responder. To conclude, vaccination of HCT donors against HBV allows a better response to vaccination in the respective HCT recipients. Double doses of rHBsAg should be considered in patients with cGVHD and in those not immunized before HCT. A dedicated intensified vaccination schedule should be administered to WRs.

Efficacy and Safety of Revaccination against Tetanus, Diphtheria, Haemophilus influenzae Type b and Hepatitis B Virus in a Prospective Cohort of Adult Recipients of Allogeneic Hematopoietic Stem Cell Transplantation

Data on immunogenicity and safety of the recommended revaccination schedule against diphtheria, tetanus, poliomyelitis, pertussis, Haemophilus influenzae type b (Hib), and hepatitis B in adult allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients are limited. This prospective single-center cohort study (April 2014 to March 2018) included adult allo-HSCT recipients referred to a dedicated vaccinology consultation and vaccinated with the pediatric combined diphtheria, tetanus, acellular pertussis, hepatitis B virus, inactivated poliovirus, and Haemophilus influenzae type b (DTaP(±HB)-IPV-Hib) vaccine (3 doses 1 month apart, booster dose 1 year later). The proportion of responders to tetanus, diphtheria, Hib, and hepatitis B vaccine and geometric mean concentrations (GMCs) of antibodies were assessed before and up to 24 months after vaccination. A total of 106 patients were vaccinated at a median (interquartile range) time of 12.4 (10 to 18.4) months post-transplant. At 5.3 (4.8 to 6.6) and 23.1 (21.1 to 25.1) months after vaccine initiation, high and sustained rates of protective antibody titers were achieved for tetanus (97.8% [95% confidence interval (95% CI), 92.4% to 99.7%], n = 91/93 and 100% [95% CI, 92% to 100%], n = 44/44), diphtheria (94.6% [95% CI, 87.9% to 98.2%], n = 88/93 and 90.9% [95% CI, 78.3% to 97.5%], n = 40/44), Hib (96.6% [95% CI, 90.4% to 99.3%], n = 85/88 and 93% [95% CI, 80.9% to 98.5%], n = 40/43), and hepatitis B (83.5% [95% CI, 73.5% to 90.9%], n = 66/79 and 81.1% [95% CI, 64.8% to 92%], n = 30/37). Underlying disease, stem cell source, chronic graft-versus-host-disease, and extracorporeal photopheresis differentially influenced GMCs of tetanus, diphtheria, and hepatitis B antibodies after 3 doses but not in the long term (24 months). Six (5.7%) patients experienced mild side effects. The pediatric DTaP(±HB)-IPV-Hib vaccine was safe and effective in eliciting a sustained protective humoral response in adult allo-HSCT recipients. Hepatitis B revaccination might be optimized by using higher antigen doses.

Determining Whether Prophylactic Antiviral Treatment Is Necessary in HBsAg-Negative/HBcAb-Positive Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation

The incidence of hepatitis B virus (HBV) infection is high in the Asian population. Increasing attention is being given to the risk of HBV reactivation in hepatitis B core antibody-positive [HBcAb(+)] patients during immunosuppressive therapy. Knowledge of HBV reactivation in hematopoietic stem cell transplantation (HSCT) is limited. Moreover, the effect of hepatitis B surface antibody (HBsAb) on HBV reactivation in HBcAb(+) patients during HSCT remains uncertain. We sought to investigate the role of HBsAb and the need for prophylactic antiviral treatment in hepatitis B surface antigen-negative [HBsAg(-)]/HBcAb(+) patients during HSCT. We classified 665 HBsAg(-) HSCT recipients into 4 groups: HBcAb(-)HBsAb(-) (n = 189), HBcAb(-)HBsAb(+) (n = 176), HBcAb(+)HBsAb(-) (n = 49), and HBcAb(+)HBsAb(+) (n = 251). HBV reactivation was identified in 16 patients after HSCT. The median time to HBV reactivation was 645 days (range, 455 to 1957 days) after transplantation. The cumulative HBV reactivation rate was significantly higher in the HBcAb(+)HBsAb(-) group compared with the HBcAb(+)HBsAb(+), HBcAb(-)HBsAb(-), and HBcAb(-)HBsAb(+) groups, respectively (P< .001). Notably, the risk of HBV reactivation was significantly higher in the HBcAb(+)HBsAb(-) group compared with the HBcAb(+)HBsAb(+) group (P= .007; hazard ratio, 4.750; 95% confidence interval, 1.531 to 14.737). Our results point to a protective role of HBsAb in HBV-resolved patients undergoing HSCT and indicate that prophylactic anti-HBV treatment might not be mandatory for HBsAg(-), HBcAb(+)HBsAb(+) patients following HSCT. The surveillance protocol of intense follow-up early (HBV DNA and HBsAg monthly) might not be necessary.

HBV Reactivation in Patients Undergoing Hematopoietic Stem Cell Transplantation: A Narrative Review

HBV reactivation (HBVr) can occur due to the ability of HBV to remain latent in the liver as covalently closed circular DNA and by the capacity of HBV to alter the immune system of the infected individuals. HBVr can occur in patients undergoing hematopoietic stem cell transplantation (HSCT) with a clinical spectrum that ranges from asymptomatic infection to fulminant hepatic failure. The risk of HBVr is determined by a complex interplay between host immunity, virus factors, and immunosuppression related to HSCT. All individuals who undergo HSCT should be screened for HBV. HSCT patients positive for HBsAg and also those HBcAb-positive/HBsAg-negative are at high risk of HBV reactivation (HBVr) due to profound and prolonged immunosuppression. Antiviral prophylaxis prevents HBVr, decreases HBVr-related morbidity and mortality in patients with chronic or previous HBV. The optimal duration of antiviral prophylaxis remains to be elucidated. The vaccination of HBV-naïve recipients and their donors against HBV prior to HSCT has an important role in the prevention of acquired HBV infection. This narrative review provides a comprehensive update on the current concepts, risk factors, molecular mechanisms, prevention, and management of HBVr in HSCT.

Vaccination of haemopoietic stem cell transplant recipients: guidelines of the 2017 European Conference on Infections in Leukaemia (ECIL 7)

Infection is a main concern after haemopoietic stem cell transplantation (HSCT) and a major cause of transplant-related mortality. Some of these infections are preventable by vaccination. Most HSCT recipients lose their immunity to various pathogens as soon as the first months after transplant, irrespective of the pre-transplant donor or recipient vaccinations. Vaccination with inactivated vaccines is safe after transplantation and is an effective way to reinstate protection from various pathogens (eg, influenza virus and Streptococcus pneumoniae), especially for pathogens whose risk of infection is increased by the transplant procedure. The response to vaccines in patients with transplants is usually lower than that in healthy individuals of the same age during the first months or years after transplant, but it improves over time to become close to normal 2-3 years after the procedure. However, because immunogenic vaccines have been found to induce a response in a substantial proportion of the patients as early as 3 months after transplant, we recommend to start crucial vaccinations with inactivated vaccines from 3 months after transplant, irrespectively of whether the patient has or has not developed graft-versus-host disease (GvHD) or received immunosuppressants. Patients with GvHD have higher risk of infection and are likely to benefit from vaccination. Another challenge is to provide HSCT recipients the same level of vaccine protection as healthy individuals of the same age in a given country. The use of live attenuated vaccines should be limited to specific situations because of the risk of vaccine-induced disease.

Expansion of viral variants associated with immune escape and impaired virion secretion in patients with HBV reactivation after resolved infection

HBV reactivation could be induced under immunosuppressive conditions in patients with resolved infection. This study aimed to clarify the viral factors associated with the pathogenesis of HBV reactivation in association with the immunosuppressive status. Whole HBV genome sequences were determined from the sera of 24 patients with HBV reactivation, including 8 cases under strong immunosuppression mediated by hematopoietic stem cell transplantation (HSCT) and 16 cases without HSCT. Ultra-deep sequencing revealed that the prevalence of genotype B and the ratio of non-synonymous to synonymous evolutionary changes in the surface (S) gene were significantly higher in non-HSCT cases than in patients with HSCT. Those non-synonymous variants included immune escape (6/16 cases) and MHC class II-restricted T-cell epitope variants (6/16 cases). Furthermore, reactivated HBV in 11 of 16 (69%) non-HSCT cases possessed substitutions associated with impaired virion secretion, including E2G, L77R, L98V, T118K, and Q129H in the S region, and M1I/V in the PreS2 region. In conclusion, virologic features of reactivated HBV clones differed depending on the intensity of the immunosuppressive condition. HBV reactivation triggered by immunosuppressive conditions, especially those without HSCT, was characterized by the expansion of variants associated with immune escape, MHC class II-restricted T-cell epitope alterations, and/or impaired virion secretion.

Vaccinating donors for hematopoietic cell transplantation: A systematic review and future perspectives

Allogeneic hematopoietic cell transplantation (Allo-HCT) recipients are at an increased risk of infectious complications, which is a major cause of morbidity and mortality post-transplant. Vaccination of donors is one of the strategies that has been studied to improve immune reconstitution post-transplant, however the efficacy and safety of this strategy is not well reviewed in the literature. In this systematic review we sought to evaluate the current strategies of donor vaccination along with their immunogenicity, effectiveness and safety. Utilizing strict selection criteria with defined MeSH terminology, an electronic search was conducted from the following databases: Medline, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Scopus. Abstracts of various professional society meetings were also screened and hand searching of various reviews and guideline articles was carried out. The full text of 52 articles were reviewed, from which 5 articles satisfied the inclusion/exclusion criteria for effectiveness and immunogenicity trials and 1 article was included for safety data. Jadad score was used to assess the quality of included studies. The results of the included studies were inconsistent, and the studies were generally of suboptimal methodological quality. Most of the included studies (n = 3) investigated the use of more than one vaccine, however not all commonly used vaccines in HCT were investigated. None of the studies reported any long-term benefits for HCT recipients of vaccinated donors. Only one study reported safety data of using vaccination in donors. Given the suboptimal quality of the studies, and questionable effectiveness, donor vaccination cannot be recommended for all. Prospective high-quality vaccine trials in HCT donors are needed.

Reactivation of occult HBV infection in an HIV/HCV Co-infected patient successfully treated with sofosbuvir/ledipasvir: a case report and review of the literature

BACKGROUND

Reactivation of occult or inactive Hepatitis B virus (HBV) infection during immunosuppressant treatments is well known and widely described in literature. The same observation has been made in Hepatitis C (HCV)-infected patients previously exposed to HBV and treated with interferon-free DAA treatments. Because of common transmission routes, persons may have been exposed to HCV, HBV and HIV, but few cases have been reported in this scenario to date. Frequency of HBV reactivation in HIV/HCV co-infected patients previously exposed to HBV and treated with DAA remains unclear. Herein, we report an episode of HBV reactivation in an HIV/HCV co-infected patient prescribed with sofosbuvir/ledipasvir for HCV.

CASE PRESENTATION

The patient is a Caucasian 54-years old female, with HIV/HCV co-infection (genotype 4), and a previous exposure to HBV, documented by negativity of HBsAg and positivity of HBsAb and HBcAb. Her medical history included: myocardial infarct, chronic kidney disease stage 3, chronic obstructive pulmonary disease, and mild pulmonary hypertension. HCV had not been treated with interferon (IFN)-based regimens and liver stiffness was 10.5 KPa (Metavir stage F3) at hepatic elastography. Because of CKD, she was prescribed with a nucleoside reverse transcriptase (NRTI)-sparing regimen including darunavir/ritonavir plus etravirine, and thereafter with sofosbuvir/ledipasvir for 12 weeks. Four weeks after DAA termination, the patient was hospitalized with symptoms of acute hepatitis. Blood tests showed HCV RNA <12 IU/ml, but positivity of HBAg, HBeAg, and of anti-core antibodies (IgM and IgG), while anti-HBs and anti-HBe antibodies were negative. HBV DNA was 6.06 Log₁₀ IU/ml. Entecavir was started obtaining resolution of symptoms, normalization of liver enzymes, as well as reduction of HBV DNA and of quantitative HBV surface antigen.

CONCLUSIONS

This case-report highlights the risk of HBV reactivation with interferon-free DAA treatment in HIV/HCV co-infected patients previously exposed to HBV and who have contraindications for treatment with nucleoside/nucleotide reverse transcriptase Inhibitors because of comorbid conditions. In the setting of HIV infection, clinicians prescribing DAA should be aware of this risk, and HBV assessment at treatment start as well as virological monitoring during DAA treatment is recommended. Large epidemiological and virological studies are needed to investigate reactivation of occult HBV infection more in depth.

VH1 Family Immunoglobulin Repertoire Sequencing after Allogeneic Hematopoietic Stem Cell Transplantation

After allogeneic hematopoietic stem cell transplantation (HSCT), recovery of humoral immunity is essential to protect from life-threatening infections. However, monitoring the humoral immune system after transplantation with standard techniques in the clinical routine is imprecise. Here, we performed sequencing of mononuclear bone marrow cells to characterize the VH1-repertoire of switched B cells of healthy volunteers and patients undergoing HSCT. Analysis of healthy bone marrow donors and patients showed virtually no clonally related sequences between individuals. Interestingly, clonally related sequences were present in pre- and post-transplantation bone marrow of patients undergoing HSCT for acute myeloid leukemia treatment. We consistently observed such related B cell clones, irrespective of conditioning regimen, donor source or time post transplantation. In general, repertoire diversity was lower in post-HSCT as compared to pre-HSCT samples. However, post-HSCT repertoires retained highly mutated sequences, despite immunosuppressive therapy and presence of T cell deficiency after HSCT. These observations identify key properties of the recovering B cell compartment and provide a conceptual framework for the surveillance of humoral immunity after allogeneic transplantation.

Hepatitis B virus (HBV) reverse seroconversion (RS) can be prevented even in non-responders to hepatitis B vaccine after allogeneic stem cell transplantation: long-term analysis of intervention in RS with vaccine for patients with previous HBV infection

BACKGROUND

Reactivation of hepatitis B virus (HBV) infection, reverse seroconversion (RS), is a serious complication after allogeneic stem cell transplantation (alloHSCT). We previously conducted a post-transplant hepatitis B vaccine intervention trial and demonstrated the vaccine efficacy in preventing HBV-RS. This report is an update of the hepatitis B vaccine study.

METHODS

In this trial, 21 patients were enrolled and received a standard 3-dose regimen of hepatitis B vaccine after discontinuation of immunosuppressants, whereas 25 transplant recipients with previous HBV infection did not receive the vaccine and served as controls.

RESULTS

None of the 21 patients in the vaccine group developed HBV-RS and 12 controls developed HBV-RS in median follow-up periods of 60 months (range 13-245). HBV vaccine resulted in a positive value of hepatitis B surface antibody (HBsAb) titer in 9 patients, while HBsAb remained negative in 12 patients. Presence of a high titer of HBsAb before vaccination was associated with conversion into HBsAb positivity after vaccination.

CONCLUSION

These results demonstrated the long-term effects of HBV vaccine for preventing HBV-RS after alloHSCT. Of note, no HBV-RS occurred, even in patients who did not achieve conversion into HBsAb positivity after vaccination.

Immune reconstitution after hematopoietic cell transplantation

PURPOSE OF REVIEW

Successful immune reconstitution is important for decreasing posthematopoietic cell transplant (post-HCT) infections, relapse, and secondary malignancy, without increasing graft-versus-host disease (GVHD). Here we review how different parts of the immune system recover, and the relationship between recovery and clinical outcomes.

RECENT FINDINGS

Innate immunity (e.g., neutrophils, natural killer cells) recovers within weeks, whereas adaptive immunity (B and T cells) recovers within months to years. This has been known for years; however, more recently, the pattern of recovery of additional immune cell subsets has been described. The role of these subsets in transplant complications like infections, GVHD and relapse is becoming increasingly recognized, as gleaned from studies of the association between subset counts or function and complications/outcomes, and from studies depleting or adoptively transferring various subsets.

SUMMARY

Lessons learned from observational studies on immune reconstitution are leading to new strategies to prevent or treat posttransplant infections. Additional knowledge is needed to develop effective strategies to prevent or treat relapse, second malignancies and GVHD.

Development of immunity against hepatitis B virus after donor lymphocyte infusion in a peripheral blood stem cell transplantation recipient with chronic hepatitis B

Hepatitis B virus (HBV) infection is one of the main concerns in blood and marrow transplantation (BMT) patients for possible breakthrough hepatitis. Active recipient immunization against HBV was found to be ineffective and many studies had showed that the adoptive transfer of immunity against hepatitis B virus would be possible by BMT with unknown duration and mechanism. A 46-year-old female patient with chronic hepatitis B had persistent detectable HBV DNA and positive serum hepatitis B e antigen (HBeAg), even while on long-term lamivudine and adefovir therapy. She received allogeneic matched unrelated donor peripheral blood stem cell transplantation (allo-MUD-PBSCT) for her refractory acute myeloid leukemia (AML). The HBV DNA became undetectable and she developed HBeAg seroconversion after PBSCT. Her hepatitis B surface antigen (HBsAg) remained positive, which disappeared later, along with the development of antibody to HBsAg after one shot of donor lymphocyte infusion (DLI) as a boost against her AML. In summary, BMT from an immunized donor would probably bring adoptive immunity against HBV. This adoptive immunity might be further enhanced by the subsequent DLI.

Changes of hepatitis B virus serologic status after allogeneic hematopoietic stem cell transplantation and impact of donor immunity on hepatitis B virus

Reverse seroconversion (RS) of Hepatitis B virus (HBV) has been reported after allogeneic transplantation with an incidence of 14% to 86%. However, most prior studies on HBV RS were performed in HBV nonendemic areas. In this study, the frequency of HBV RS at a single center in Korea, endemic for HBV, was evaluated. Also, the influence of the donor's immunity for HBV on posttransplantation HBV serologic changes in recipients was also investigated. A total of 288 patients underwent allogeneic transplantation between February 1996 and June 2008. We retrospectively reviewed the medical records of 288 patients and their paired donors. Among the 268 HBsAg(-) patients, 205 were assessed for posttransplantation HBsAg, and 114 (55.6%) of 205 had HBcAb before transplantation. With a median follow-up of 77.9 months, 3 of 114 patients experienced HBV RS (2.6%). With regard to donor immunity, significantly more patients with anti-HBs(-) donors experienced anti-HBs loss (P = .006), and the donor anti-HBs showed significant protective effects against the anti-HBs loss with an HR of 0.4. HBV RS after allogeneic transplantation may not be as common in HBV endemic areas. Also, donor anti-HBs showed a significant favorable effect on maintaining HBV immunity in recipients.

Risk of de novo hepatitis in liver recipients from hepatitis-B core antibody-positive grafts - a systematic analysis

SkagenMany transplant programs utilize liver grafts from hepatitis-B core antibody (HBcAb)-positive and hepatitis-B surface antigen (HBsAg)-negative donors. However, there is risk for de novo hepatitis B (DNH) in recipients of these grafts. We reviewed 26 studies reporting the rates of DNH in recipients receiving HBcAb-positive liver grafts. Four hundred and sixty-two donor-recipient pairs were included to evaluate the risk of DNH stratified by the recipient's immune status to hepatitis B and type of prophylactic therapy given, if any. The rate of DNH was highest (58%) in the stratum of hepatitis-B (HBV) naïve recipients who did not receive prophylaxis. In HBV naïve recipients, prophylactic therapy (lamivudine and/or hepatitis-B immunoglobulin - HBIG) reduced DNH to 11% (odds ratio [OR] = 11.1, 95% CI 4.98-25, p < 0.0001 for DNH without prophylaxis). Recipients with hepatitis-B surface antibody (HBsAb) positivity had DNH rates of 18% without prophylaxis and 0% with prophylaxis (OR = 9.2, 95% CI 1.1-83.3, p = 0.039). Recipients with both HBsAb and HBcAb positivity had DNH rates of 4% without prophylaxis and 3% with prophylaxis (p = 1.00), while recipients with HBcAb positivity alone had DNH rates of 14% without prophylaxis and 3% with prophylaxis (p = 0.21). There was no significant difference between the types of HBV prophylaxis received whether lamivudine, HBIG or both. However, in the subgroup who received HBIG alone, rates of DNH were higher after cessation of HBIG prophylaxis compared to DNH rates with indefinite HBIG (p = 0.0002). In summary, the risk of DNH is highest for HBV naïve liver recipients from HBcAb-positive donors. Recipients who are HBV naïve as well as those recipients with isolated HBsAb positivity derive significant benefit from HBV prophylaxis after transplantation with a HBcAb-positive graft. The ideal prophylactic regimen for prevention of DNH is unclear, but based on our analysis of the literature, antivirals alone may suffice. More data are needed with the newer antivirals for hepatitis B.

Hepatitis B virus reactivation following allogeneic hematopoietic stem cell transplantation

Reactivation of resolved hepatitis B virus (HBV) infection has been reported in allogeneic hematopoetic stem cell transplantation (HSCT) recipients, but its epidemiology is not well characterized. We performed a retrospective assessment of the timing and risk factors of HBV reactivation among patients with resolved HBV infection undergoing allogeneic HSCT between January 2000 and March 2008. HBV reactivation was defined as development of positive hepatitis B surface antigen after transplant. Among the 61 patients with resolved HBV infection before transplant (hepatitis B core antibody-positive, hepatitis B surface antigen-negative), 12 (19.7%) developed HBV reactivation. The cumulative probability of HBV reactivation 1, 2, and 4 years after transplant was 9.0%, 21.7%, and 42.9%, respectively. In a time-dependent Cox model, the adjusted hazard ratio (HR) of HBV reactivation for patients with pretransplant hepatitis B surface antibody levels <10 milli-international units per milliliter (mIU/mL) was 4.56 (95% confidence interval [CI] 1.23-16.9) compared to those with levels > or =10 mIU/mL; the adjusted HR among patients who developed extensive chronic graft-versus-host disease (cGVHD) was 7.21 (95% CI 1.25-41.5) compared to those who did not. HBV reactivation is a common late complication among allogeneic HSCT recipients with pretransplant resolved infection. Screening for HBV reactivation should be considered for at-risk HSCT recipients. In this cohort, HBV reactivation often developed in patients with cGVHD. Liver biopsy was useful in those patients with both to delineate the contribution of each to liver dysfunction.

HB vaccination in the prevention of viral reactivation in allogeneic hematopoietic stem cell transplantation recipients with previous HBV infection

Hepatitis B virus (HBV)-reverse seroconversion (RS) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a frequent late-onset complication in recipients with previous HBV infection. We followed 38 allo-HSCT recipients with previous HBV infection, and conducted posttransplant HB vaccine intervention in 13 recipients. First, we followed the recipients without any intervention (historic control) until 2003; hence, we commenced HB vaccination. Out of the patients who underwent transplantation after 2003, 13 recipients were immunized by a standard three-dose regimen after immunosuppressant cessation (vaccine group), whereas 12 recipients were observed without any intervention (nonvaccine group). Eight of the 13 historic control group recipients and 3 of the 12 nonvaccine group recipients, but none of the 13 vaccine group recipients, suffered HBV-RS. Cumulative risks of HBV-RS at 3 years post-HSCT in the historic control, nonvaccine and vaccine groups were 41%, 39%, and 0% respectively (P=.022). We therefore conclude that intervention with HB vaccines is significantly effective in preventing post-HSCT HBV-RS.