Reactivation of hepatitis B virus infection in an anti-HBc and anti-HBs positive patient after allogeneic bone marrow transplantation

Reactivation of resolved hepatitis B virus infection combined with nephrotic syndrome in a patient after allogeneic haematopoietic stem cell transplantation

Background

After allogeneic haematopoietic stem cell transplantation (allo-HSCT), Hepatitis B virus reactivation (HBVr) can be observed in patients with previous resolved Hepatitis B virus (HBV) infections. Nephrotic syndrome (NS) is the main clinical manifestation of HBsAg-positive glomerulonephritis. However, the development of HBVr combined with NS after allo-HSCT is uncommon.

Case presentation

We presented a case of a 47-year-old female with acute myelogenous leukemia who underwent HLA-identical sibling allo-HSCT and achieved leukemia free survival. She had pretransplant serological markers of a resolved HBV infection (HBsAg-negative, anti-HBc and anti-HBs positive). However, she developed HBVr combined with nephrotic syndrome (NS) 16 months after HSCT. Her histological renal lesion was mesangial proliferative glomerulonephritis. IgA+, IgM+, and C1q deposits but not HBV antigens (HBsAg and HBcAg) were identified in her renal biopsy material. Long-term entecavir and immunosuppression resulted in decrease of HBV virus replication, amelioration of proteinuria and stabilisation of renal function.

Conclusions

Entecavir combined with immunosuppression has efficacy in the treatment of HBVr combined with NS after allo-HSCT, but long course of treatment is needed. Closely monitoring and antiviral prophylaxis might be necessary for allo-HSCT recipients to prevent reactivation of resolved HBV infection and its related complications.

Short-course tocilizumab increases risk of hepatitis B virus reactivation in patients with rheumatoid arthritis: a prospective clinical observation

AIM

To investigate the impact of short-course tocilizumab (TCZ) on hepatitis B virus (HBV) reactivation in rheumatoid arthritis (RA) patients.

METHODS

RA patients with moderate to high disease activity, with at least one feature of poor prognosis and inadequate response to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) were recruited. Three consecutive doses of intravenous TCZ were given combined with csDMARDs. Liver function and HBV infection status were evaluated at baseline, weeks 4, 8 and 12.

RESULTS

Sixty-three RA patients who were qualified for statistics were classified as chronic HBV infection (n = 7), resolved HBV infection (n = 41) and non-HBV infection (n = 15). Three patients with chronic HBV infection and without antiviral prophylaxis developed HBV reactivation after 1-3 doses of TCZ. They were asymptomatic of hepatitis B with normal aminotransferases and the HBV-DNA of three patients with HBV reactivation became undetectable after therapeutic antiviral therapy. No HBV reactivation developed in patients with resolved HBV infection. Aminotransferases elevated in 22% of all patients, but became elevated ≥ 2-fold of normal range in only two patients: one was treated with adefovir before TCZ for active hepatitis B and the other had resolved HBV infection, with aminotransferases returning to normal 4 weeks later. Thirty-two patients with resolved HBV infection had positive anti-HBs (≥ 10 IU/L) which is a protective antibody. The anti-HBs titer reduced significantly at week 4 and week 8 after the first dose of TCZ compared to baseline (P < 0.05) and even reduced to negative in six (19%). The anti-HBs did not return to positive in three patients during follow-up of 12-36 weeks.

CONCLUSIONS

This prospective clinical observation preliminarily indicated three-dose TCZ combined with csDMARDs might increase the risk of HBV reactivation in RA patients with chronic HBV infection, but in this study patients remained asymptomatic and had a benign outcome after antiviral treatment. To identify the exact risk of TCZ on HBV infection and the prognosis of TCZ-related HBV reactivation, further studies with larger sample sizes and fewer confounding factors are needed.

Incidence and characteristics of HBV reactivation in hematological malignant patients in south Egypt

AIM: To investigate characteristics of hepatitis B virus (HBV) implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.

METHODS: Serum samples were collected from 53 patients with hematological malignancies negative for hepatitis B surface antigen (HBsAg) before the start of and throughout the chemotherapy course. HBV reactivation was diagnosed when the HBsAg status changed from negative to positive after the initiation of chemotherapy and/or when HBV DNA was detected by real-time detection polymerase chain reaction (RTD-PCR). For detecting the serological markers of HBV infection, HBsAg as well as antibodies to the core antigen (anti-HBc) and to the surface antigen were measured in the sera by CEIA. Nucleic acids were extracted from sera, and HBV DNA sequences spanning the S gene were amplified by RTD-PCR. The extracted DNA was further subjected to PCR to amplify the complete genome as well as the specific genomic sequences bearing the enhancer II/core promoter/pre-core/core regions (nt 1628-2364). Amplicons were sequenced directly.

RESULTS: Thirty-five (66%) of the 53 HBsAg-negative patients were found to be negative serologically for anti-HBc, and the remaining 18 (34%) patients were positive for anti-HBc. Five of the 53 (9.4%) patients with hematologic malignancies experienced HBV reactivation. Genotype D1 was detected in all five patients. Four types of mutant strains were detected in the S gene product of HBV strains and were isolated from 3 patients with HBV reactivation: T/S120, L143, and I126. HBV DNA was detected in the pretreatment HBsAg-negative samples in one of the five patients with HBV reactivation. In this patient, sequences encompassing the HBV full genome obtained from sera before the start of chemotherapy and at the time of de novo HBV hepatitis were detected and it showed 100% homology. Furthermore, in the phylogenetic tree, the sequences were clustered together, thereby indicating that this patient developed reactivation from an occult HBV infection.

CONCLUSION: Past infection with HBV is a risk factor for HBV reactivation in Egypt. Mandatory anti-HBc screening prior to chemotherapy in patients with hematological malignancies is recommended.

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.

Resolved hepatitis B virus infection is not associated with worse outcome after allogeneic hematopoietic stem cell transplantation

Serologic evidence of resolved hepatitis B virus (HBV) infection has been associated with reactivation of hepatitis after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the true impact of this finding is unknown. We conducted a retrospective matched-control analysis of the outcomes of 76 patients with positive HBV core antibody (HBcAb) and negative HBV surface antigen (HBsAg) at the time of allo-HSCT for hematologic or solid malignancies. Control patients (matched controls), with negative serology for HBV and other viral hepatitides, were matched by age, diagnosis, disease risk, intensity of conditioning regimen, and donor type. In addition, the HBcAb-positive patients and all seronegative patients (all controls, n = 1858) undergoing transplantation during the same period were compared to adjust for other confounding effects. Patient characteristics and baseline hepatic function studies were similar in the HBcAb-positive and matched control groups. The cumulative incidence of hepatitis B reactivation (defined as the emergence of HBsAg in serum) was 11.6% at 3 years. There were no significant differences in overall survival, relapse, nonrelapse mortality, and incidence of acute graft-versus-host disease between the HBcAb-positive and control groups. Our data suggest that seropositivity for HBcAb and seronegativity for HBsAg at the time of transplantation does not seem to adversely affect outcome after allo-HSCT.

Risk of hepatitis B surface antigen seroreversion after allogeneic hematopoietic SCT

Allogeneic hematopoietic SCT (HSCT) increases the risk of hepatitis B virus (HBV) reactivation in hepatitis B surface antigen (HBsAg) carriers but the incidence, risk factors and course of HBV reactivation after HSCT in HBsAg-negative/anti-hepatitis B core antigen (anti-HBc)-positive recipients are not well known. A total of 50 HBsAg-negative/anti-HBc-positive HSCT recipients with onco-hematological diseases, underwent sequential clinical and laboratory examinations, including serum HBsAg, during follow-up. Serum HBV DNA collected at HSCT was retrospectively amplified by a sensitive PCR assay. During 17 months of follow-up, six (12%) patients had seroreverted to HBsAg, 7-32 months after HSCT, with 1- and 5-year cumulative rates of 13 and 22%. HBsAg seroreversion was associated with serum HBeAg higher than 8 log₁₀ copies per ml HBV DNA and a 1.5 to 36 fold increase of serum alanine aminotransferase leading to HBeAg-positive chronic hepatitis B in all patients. Patients with chronic onco-hematological disease and long-lasting immunosuppression following HSCT had a higher risk of HBsAg seroreversion independently of serum HBV DNA levels at HSCT. HBsAg-negative/anti-HBc-positive HSCT recipients with chronic onco-hematological disease carry a significant risk of HBsAg seroreversion and HBeAg-positive chronic hepatitis B, independently of serum levels of HBV DNA at transplantation.

Retrospective and prospective studies of hepatitis B virus reactivation in malignant lymphoma with occult HBV carrier

BACKGROUND

In surface antigen of hepatitis B virus (HBsAg)-positive carrier for anticancer treatment of malignant lymphoma, it is well recognized that reactivation of hepatitis B virus (HBV) occasionally occurs. However, there have been only a few studies of HBV reactivation in serum HBsAg-negative and hepatitis B core antigen (HBcAb)-positive occult HBV carriers. We looked at both retrospective and prospective studies to determine the prevalence, clinical course and risk factor of HBV reactivation during chemotherapy in lymphoma patients.

PATIENTS AND METHODS

Forty-eight of 127 (37.8%) lymphoma patients were HBsAg negative and HBcAb positive, and 24 of these patients were then given liver function tests and HBsAg tests monthly and serum HBV DNA every 3 months.

RESULTS

HBV reactivation was observed in two patients (4.1%) who had received intensive chemotherapy including steroid and rituximab. Immediate administration of entecavir therapy after elevation of HBV DNA level was conducted, and this resulted in reduction of it and improvement of liver function test.

CONCLUSIONS

Rituximab plus steroid-containing regimens may increase the risk of HBV reactivation in HBsAg-negative and HBcAb-positive lymphoma patients. More ambitious prospective studies are required to establish clinically useful or cost-effective follow-up methods for control of HBV reactivation in lymphoma patients with occult HBV infection.

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.

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.

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.

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.

Viral Hepatitis: Manifestations and Management Strategy

Viral hepatitis is the third most common cause of liver disease in allogeneic transplant recipients and causes significant morbidity and mortality. When treating patients with hematological malignancies, an emphasis should be placed on identification of patients at risk for viral hepatitis with appropriate screening. Initial screening serology should include anti-HCV, HBsAg, anti-HBs, and anti-HBc testing. When hepatitis B exposure has been documented, prophylaxis of viral reactivation for all HBsAg-positive patients with a nucleoside analogue should be implemented. HCV infection appears to have little short-term impact on survival after bone marrow transplantation, but is a risk factor for veno-occlusive disease (VOD) and graft-versus-host disease (GVHD). In the long-term survivor, HCV infection can lead to significant morbidity and mortality due to the development of cirrhosis, decompensation, and liver cancer. Since effective antiviral therapies are available for both hepatitis B and C, routine screening and selected intervention is recommended once reactivation and disease recurrence is documented. In this chapter we will highlight the mechanisms of virus reactivation, clinical manifestations, and management strategies to minimize acute and chronic morbidity in this population.

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.

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

Reactivation of resolved hepatitis B virus (HBV) infection, which is known as reverse seroconversion (RS), has been reported as a rare complication of allogeneic hematopoietic stem cell transplantation. We retrospectively studied HBV serologic markers in 14 recipients with pretransplant anti-hepatitis B surface antigen antibody (anti-HBs). Progressive decreases in anti-HBs titer were observed in all cases. In 12 cases, anti-HBs titer had decreased to under the protective value. RS occurred in seven cases after disappearance of anti-HBs. Although reseroconversion occurred in five cases, two cases remained in an HBV-carrier status after resolution of hepatitis. In the other five cases, RS did not occur even after disappearance of anti-HBs. The actual risks of anti-HBs disappearance and RS were estimated to be 75.0% and 39.8% at 2 years and 100.0% and 70.0% at 5 years, respectively. In conclusion, RS is a late-onset complication with high frequency that can be predicted by careful monitoring of progressive decrease in anti-HBs titer.

Reactivation of resolved hepatitis B virus infection after allogeneic haematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation after allogeneic haematopoietic stem cell transplantation (allo-HSCT) is well known in HBsAg-positive carriers but has only occasionally been reported in patients with resolved HBV infection. We investigated six allo-HSCT recipients with pretransplant anti-HBs and anti-HBc antibodies for serologic markers of HBV infection and for the presence of HBV-DNA in serum. Reverse seroconversion, that is, reappearance of HBsAg after a gradual loss of anti-HBs, but no severe liver damage was observed in three patients at 14, 22 and 12 months after HSCT, respectively. There was an increase in HBV-DNA concentration prior to reverse seroconversion. One patient was repeatedly HBV-DNA positive (10(2)-10(3) copies/ml) without reverse seroconversion. Sequencing of the HBsAg and precore region derived from the four HBV-DNA-positive patients showed no relevant mutations. In conclusion, this study demonstrated a high risk (50%) of reverse seroconversion in allo-HSCT recipients with resolved HBV infection. A highly sensitive HBV-DNA assay (TaqMan-PCR) allowed early identification of the individual patients at risk.

Hepatitis B virus reactivation after kidney transplantation and new onset lymphoma

A case of hepatitis B virus (HBV) reactivation after kidney transplantation is reported. The presence of antibodies against hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) before transplantation indicated previous infection with HBV. Eight years after transplantation, a diffuse, large B-cell lymphoma occurred, and the patient was positive for HBsAg and hepatitis B e antigen, in association with normal activity of serum aminotransferases. Postmortem liver histology did not show any sign of portal tract or lobular inflammation despite the presence at immunostaining of extensive intranuclear and cytoplasmic positivity for HBcAg, indicating active viral replication. Natural immunity to HBV may not protect against reactivation in patients with a suppressed immune system. In this setting, periodic follow-up of HBV serology in patients at highest risk for HBV reactivation to allow for early diagnosis and prompt treatment with lamivudine is highly recommended.

Frequency and load of hepatitis B virus DNA in first-time blood donors with antibodies to hepatitis B core antigen

The objective of this study was to determine the frequency and load of hepatitis B virus (HBV) DNA in anti-HBc-positive first-time blood donors; it was designed to contribute to determining whether anti-HBc screening of blood donations might reduce the residual risk of posttransfusion HBV infection. A total of 14 251 first-time blood donors were tested for anti-HBc using a microparticle enzyme immunoassay; positive results were confirmed by a second enzyme-linked immunosorbent assay (ELISA). For the detection of HBV DNA from plasma samples, we developed a novel and highly sensitive real-time polymerase chain reaction (PCR) assay. The 95% detection limit of the method amounted to 27.8 IU/mL, consistent with the World Health Organization (WHO) international standard for HBV DNA. A total of 216 blood donors (1.52%) tested anti-HBc-positive in both tests, and 205 of them (16 HBsAg(+), 189 HBsAg(-)) were tested for HBV DNA. In 14 (87.5%) of the HBsAg-positive blood donors, HBV DNA was repeatedly detected, and in 3 (1.59%) of the HBsAg-negative donors, HBV DNA was also found repeatedly. In the 3 HBV DNA-positive, HBsAg-negative cases, anti-HBe and anti-HBs (> 100 IU/L) were also detectable. HBV DNA in HBsAg-negative as well as HBsAg-positive samples was seen at a low level. Thus, HBV DNA is sometimes found in HBsAg-negative, anti-HBc-positive, and anti-HBs-positive donors. Retrospective studies on regular blood donors and recipients are necessary to determine the infection rate due to those donations. Routine anti-HBc screening of blood donations could probably prevent some transfusion-transmitted HBV infections.