Active vaccination to prevent de novo hepatitis B virus infection in liver transplantation

The shortage of organ donors mandates the use of liver allograft from anti-HBc(+) donors, especially in areas highly endemic for hepatitis B virus(HBV) infection. Theincidence of de novo hepatitis B infection(DNH) is over 30%-70% among recipients of hepatitis B core antibody(HBcA b)(+) grafts without any prophylaxis after liver transplantation(LT). Systematic reviews showed that prophylactic therapy [lamivudine and/or hepatitits B immunoglobulin(HBIG)] dramatically reduces the probability of DNH. However, there are limited studies regarding the effects of active immunization to prevent DNH, and the role of active vaccination is not welldefined. This review focuses on the feasibility and efficacy of pre- and post-LT HBV vaccination to prevent DNH in HBsA g(-) recipient using HBcA b(+) grafts. The presence of HBs Ab in combination with lamivudine or HBIG results in lower incidence of DNH and may reduce the requirement of HBIG. There was a trend towards decreasing incidence of DNH with higher titers of HBs Ab. High titers of HBs Ab( 1000 IU/L) achieved after repeated vaccination could eliminate the necessity for additional antiviral prophylaxis in pediatric recipients. In summary, active vaccination with adequate HBsA b titer is a feasible, cost-effective strategy to prevent DNH in recipients of HBc Ab(+) grafts. HBV vaccination is advised for candidates on waiting list and for recipients after withdrawal of steroids and onset of low dose immunosuppression after transplantation.     

Prevention of hepatitis B virus infection from hepatitis B core antibody-positive donor graft using hepatitis B immune globulin and lamivudine in living donor liver transplantation.

BACKGROUND: Hepatic grafts from hepatitis B surface antigen-negative and anti-core antibody (HBcAb)-positive donors have been shown to transmit hepatitis B virus (HBV) infection. Recently, it has been reported that combined hepatitis B immune globulin (HBIG) and lamivudine therapy is effective in the prevention of hepatitis B recurrence after living donor liver transplantation (LDLT). In this report, we assessed the efficacy of combined HBIG and lamivudine therapy in preventing HBV transmission by graft with HBcAb-positive donors. METHODS: We studied 22 patients who had undergone LDLT with allografts from HBcAb-positive living donors at Gunma University Hospital and Kyushu University Hospital. Long-term combined HBIG and lamivudine therapy were administrated to all recipients. Serum samples from the donor and recipient were tested for HBcAb, HBV DNA, and hepatitis B surface antibody. Liver biopsies from grafts were tested for HBV DNA. RESULTS: All recipients were HBcAb negative before LDLT. All of the donor livers were HBV DNA positive at the time of LDLT. All of the recipients had HBsAb titers greater than 300 mIU/ml 4 weeks after LDLT, and remained 100 mIU/ml thereafter. None of the recipients have become infected with HBV with a follow-up of 25-86 months. CONCLUSIONS: Perioperative combined HBIG and lamivudine therapy can prevent HBV infection in recipients who receive liver grafts from HBcAb-positive donors.     

Active immunization against de novo hepatitis B virus infection in pediatric patients after liver transplantation

The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.     

Vaccination against hepatitis B in patients with chronic liver disease awaiting liver transplantation.

BACKGROUND: Most transplant centers in the United States immunize patients awaiting liver transplantation against hepatitis B to prevent acquisition of hepatitis B through transplantation (de novo hepatitis B). A recent study showed that only 16% of patients with cirrhosis awaiting liver transplantation responded to single-dose recombinant vaccine. METHODS: We studied the immunogenicity of double-dose recombinant vaccine in patients with cirrhosis awaiting liver transplantation. RESULTS: Over a 4-year period (January 1994 to December 1997), 140 patients with cirrhosis without past or current hepatitis B infection were given double-dose recombinant vaccine (40 microg of Engerix B; SmithKline Beecham, Philadelphia, PA) at 0, 1 to 2, and 2 to 4 months. Hepatitis B surface antibody (HBsAb) was measured 1 to 3 months after completing vaccination. The response rate was 37%. However, HBsAb titers became undetectable in 35% of the responders during the post-transplant follow-up period. One hundred and thirty-seven patients underwent 144 liver transplantation procedures during the study period, and 3 patients developed de novo hepatitis B (2.2%). Livers transplanted from hepatitis B core antibody (HBcAb)-positive donors was the source of de novo hepatitis B in all cases. Two of the 3 patients who developed de novo hepatitis B were immunized before transplantation and one of them was a responder. CONCLUSION: Although the response rate to double-dose recombinant vaccines is higher than the previously reported response to single-dose vaccine, it still is less than optimal.     

Risk factors for de novo hepatitis B infection in pediatric living donor liver transplantation

AIM: To investigate the incidence of de novo hepatitis B virus (HBV) infection after pediatric living donor liver transplantation (LDLT) and to analyze the risk factors associated with this de novo HBV infection.METHODS: The clinical and laboratory data of children who underwent LDLT from June 2010 to September 2012 in First Center Hospital in Tianjin, China, were retrospectively included in the study. Intrahepatic HBV DNA in donors and recipients was quantified by real-time polymerase chain reaction using DNA extracted from formalin-fixed, paraffin-embedded tissues.RESULTS: Between June 2010 to September 2012, 32 consecutive pediatric patients underwent LDLT in our institute. Thirty LDLT patients (13 girls and 17 boys) were followed up for a median of 15 mo, of whom 53.3% (16/30) were hepatitis B core antibody (HBcAb) positive and 36.7% (11/30) were hepatitis B surface antibody (HBsAb)/HBcAb positive before transplantation. Sixteen of the children received HBcAb-positive allografts, and 43.7% (7/16) of the grafts were found to be intrahepatic HBV DNA positive. De novo HBV infection developed in 16.1% (5/30) of the children within a median of 11 mo after transplantation. All five of the HBV-infected children had received HBcAb-positive allografts, four of which were intrahepatic HBV DNA positive. Two of the children developed de novo HBV infection despite the preoperative presence of both HBsAb and HBcAbCONCLUSION: In pediatric recipients, positive intrahepatic HBV DNA in allografts could be a risk factor for de novo HBV infection from HBcAb-positive allografts. HBsAb/HBcAb positivity in pediatric LDLT patients before transplantation exhibited only weak effectiveness in protecting them against de novo HBV infection from HBcAb-positive allografts.     

Outcomes of liver transplantation using Hepatitis B core-positive liver grafts: Implications for prophylaxis

The number of patients listed for liver transplantation has outpaced the number of transplants that can be performed. This disparity between transplant candidates and the availability of donor grafts has led to an increase in mortality for patients waiting for liver transplantation. One strategy used to increase the donor pool has been the utilization of expanded donor grafts, such as those from donors with hepatitis B core antibody (anti-HBc). However, use of anti-HBc-positive grafts can potentially place the recipient at risk of de novo post-transplant hepatitis B virus (HBV) infection. The spectrum of liver disease from de novo hepatitis B ranges from mild hepatitis to graft loss. Fortunately, the risk of de novo HBV infection can be decreased with administration of oral nucleosides or nucleotides and hepatitis B immunoglobulin to the recipient. This review focuses on the epidemiology, natural history, and prophylactic strategies to reduce the risk of de novo hepatitis B in liver transplant recipients who receive anti-HBc-positive grafts.     

Application of nucleoside analogues to liver transplant recipients with hepatitis B

Hepatitis B is a common yet serious infectious disease of the liver, affecting millions of people worldwide. Liver transplantation is the only possible treatment for those who advance to end-stage liver disease. Donors positive for hepatitis B virus(HBV) core antibody(HBc Ab) have previously been considered unsuitable for transplants. However, those who test negative for the more serious hepatitis B surface antigen can now be used as liver donors, thereby reducing organ shortages. Remarkable improvements have been made in the treatment against HBV, most notably with the development of nucleoside analogues(NAs), which markedly lessen cirrhosis and reduce post-transplantation HBV recurrence. However, HBV recurrence still occurs in many patients following liver transplantation due to the development of drug resistance and poor compliance with therapy. Optimized prophylactic treatment with appropriate NA usage is crucial prior to liver transplantation, and undetectable HBV DNA at the time of transplantation should be achieved. NA-based and hepatitis B immune globulin-based treatment regimens can differ between patients depending on the patients' condition, virus status, and presence of drug resistance. This review focuses on the current progress in applying NAs during the perioperative period of liver transplantation and the prophylactic strategies using NAs to prevent de novo HBV infection in recipients of HBc Ab-positive liver grafts.     

Hepatitis B vaccination in liver transplant candidates

Liver transplantation has become the treatment of choice for patients with end-stage liver disease. De novo hepatitis B infection after liver transplantation is a rare event and usually runs a mild clinical and histological course. Despite the favourable outcome, a wide spectrum of hepatitis B virus (HBV)-associated liver disease may develop, ranging from asymptomatic carriage to severe chronic active hepatitis or cirrhosis and even fulminant hepatic failure. The achievement of protective titres of anti-HBs through vaccination has been suggested to be protective against the development of de novo HBV infection. The results of vaccination in cirrhotic patients awaiting for liver transplant have been very disappointing. High-dose/short-term schedules have been tried in transplant candidates in order to increase the response rate. New and more immunogenic formulations (containing new adjuvants or additional pre-S1/pre-S2 recombinant antigens), and, more importantly, early vaccination of potential transplant candidates at earlier stages of their liver disease should further prevent de novo hepatitis B in transplant recipients.     

Update on occult hepatitis B virus infection

The event of mutations in the surface antigen gene of hepatitis B virus(HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core(anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection(OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction(PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for:(1) patients with a previous history of chronic or acute HBV infection;(2) patients co-infected with hepatitis C virus/human immunodeficiency virus;(3) patients undergoing chemotherapy or anti-CD20 therapy;(4) recipients of organ transplant;(5) blood donors;(6) organ transplant donors;(7) thalassemia and hemophilia patients;(8) health care workers;(9) patients with liver related disease(cryptogenic);(10) hemodialysis patients;(11) patients undergoing lamivudine or interferon therapy; and(12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.     

Latent hepatitis B virus infection in healthy individuals with antibodies to hepatitis B core antigen

Several recent reports have shown that hepatitis B virus (HBV) could be frequently transmitted to the recipients from donors who have antibodies to hepatitis B core antigen (anti-HBc) through liver transplantation. We provide here the molecular evidence of latent HBV infection accompanied with ongoing viral replication in the liver tissue of anti-HBc-positive healthy individuals. HBV DNA was detectable in 13 of 14 healthy donors who were positive for both anti-HBc and antibodies to hepatitis B surface antigen (anti-HBs), but in none of 3 who were positive for anti-HBs alone. The detected HBV genomes from these subjects included covalently closed circular DNA and pregenomic RNA, the replication intermediate of HBV. Notably, 5 of 7 cases tested were predominantly infected with wild type HBV strains without any mutations in the precore and core promoter regions under the presence of circulating antibody to hepatitis B e antigen. Interestingly, a predominant clone detected in one donor showed a 63-nucleotide deletion in the precore region including an encapsidation signal sequence. Our findings indicate that the majority of healthy individuals positive for anti-HBc, which had been assumed to denote a past history of transient HBV infection, were latently infected with the episomal form of HBV accompanied by ongoing viral replication and few nucleotide mutations in the precore and core regions.     

Genetic alterations in the S gene of hepatitis B virus in patients with acute hepatitis B, chronic hepatitis B and hepatitis B liver cirrhosis before and after liver transplantation.

BACKGROUND: Several studies have shown that hepatitis B immunoglobulin (HBIG) imposes a selection pressure on the hepatitis B virus (HBV) S gene, and that the emergence of mutations in this region would make reinfection after orthotopic liver transplantation (OLT) possible. AIMS: This study was undertaken to analyze the presence of HBV S-gene mutations in the different stages of HBV infection and the relationship between HBIG therapy and the emergence of mutations in liver transplant recipients. METHODS: The frequency and location of mutations in the coding region of the HBV S gene were studied by PCR and direct sequencing in 30 patients (7 with acute self-limited hepatitis B, 16 with chronic hepatitis B and 7 recipients of (OLT) for HBV-related end stage liver disease who became reinfected). RESULTS: The average number of amino acid changes was higher in patients with a more advanced stage of disease, 0.57 mutations/100 positions in acute hepatitis B and 1.57 in chronic hepatitis B (1.28 in HBeAg-positive and 1.8 in anti-HBe-positive patients). The average number of substitutions in the transplanted patients was 2.7 before OLT and 3 after OLT. No amino acid substitutions were detected in the "a" determinant of HBsAg in acute hepatitis B, however, 8 substitutions were observed in 6 chronic patients. In 3 OLT patients, 4 substitutions were observed in samples before and after OLT. One of these patients, who had protective levels of anti-HBs, showed 3 additional new amino acid substitutions after OLT, suggesting escape mutant selection by the effect of HBIG therapy. No changes were observed between the consensus sequences obtained several years before and after transplantation, indicating consensus sequence stability. CONCLUSION: These results show that there is an accumulation of HBV S-gene mutations in HBV-related end-stage liver disease. Prophylaxis with HBIG mainly obtained from acute self-limited hepatitis patients who have a highly homogeneous viral population, may be one factor underlying the reinfection after liver transplantation.     

Adult Living Donor Liver Transplantation Using Hepatitis B Core Antibody-Positive Grafts in Korea, a Hepatitis B-endemic Region

Background/Aims

The exclusion of hepatitis B core antibody (HBcAb)-positive donors from liver transplants (LTs) due to the risk of transmitting hepatitis B virus (HBV) does not appear to be practical in Korea, where hepatitis B is endemic. This study assessed the risk of de novo HBV infection in hepatitis B surface antigen (HBsAg)-negative LT recipients receiving a liver from HBcAb-positive donors.

Methods

Of 341 adult living donor LTs conducted at our institution between March 2001 and September 2008, 176 donors (51.6%) were HBcAb-positive, and 26 HBcAb-positive grafts were transplanted to HBsAg-negative recipients. The median follow-up time after LT was 41.9 months.

Results

Without anti-HBV prophylaxis, 2 out of 26 (7.7%) HBsAg-negative recipients who received grafts from HBcAb-positive donors developed de novo HBV infection 20 and 85 months after LT. These patients had been negative for all HBV serologic markers before transplantation. In both cases, there were no abnormalities in liver function tests upon diagnosis of de novo HBV infection.

Conclusions

De novo HBV infection from HBcAb-positive donors after LT does not appear to be of great concern in terms of the number of cases in Korea because high risk patients who are HBV-negative comprise only a small proportion of the recipients. However, HBV-naïve LT recipients still carry the risk of developing de novo HBV infection as in non-HBV endemic areas.     

Prophylactic managements of hepatitis B viral infection in liver transplantation

Liver transplantation (LT) is a considerably effective treatment for patients with end-stage hepatitis B virus (HBV)-related liver disease. However, HBV infection often recurs after LT without prophylaxis. Since the 1990s, the treatment for preventing HBV reinfection after LT has greatly progressed with the introduction of hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogues (NAs), resulting in improved patient survival. The combination therapy consisting of high-dose HBIG and lamivudine is highly efficacious for preventing the recurrence of HBV infection after LT and became the standard prophylaxis for HBV recurrence. However, mainly due to the high cost of HBIG treatment, an alternative protocol for reducing the dose and duration of HBIG has been evaluated. Currently, combination therapy using low-dose HBIG and NAs is considered as the most efficacious and cost-effective prophylaxis for post-LT HBV reinfection. Recently, NA monotherapy and withdrawal of HBIG from combination therapy, along with the development of new, potent high genetic barrier NAs, have provided promising efficacy, especially for low-risk recipients. This review summarizes the prophylactic protocol and their efficacy including prophylaxis of de novo HBV infection from anti-HBc antibody-positive donors. In addition, challenging approaches such as discontinuation of all prophylaxis and active immunity through hepatitis B vaccination are discussed.     

Randomized trial of lamivudine versus hepatitis B immunoglobulin for long-term prophylaxis of hepatitis B recurrence after liver transplantation

BACKGROUND/AIMS: The long-term prophylaxis of hepatitis B after liver transplantation requires further optimization. In a randomized trial we investigated a regimen where the initially given hepatitis B immunoglobulin (HBIg) is replaced by long-term lamivudine treatment. METHODS: Twenty-four liver transplant recipients (all HBsAg-positive/HBV DNA-negative before transplantation), who had received HBIg for at least 6 months without HBV recurrence, were randomized to receive lamivudine (n = 12) or HBIg (n = 12) for 52 weeks. The efficacy criteria involved seronegativity for HBsAg and undetectable HBsAg/ HBcAg in the liver. RESULTS: Twenty-one of 24 patients completed the study without hepatitis B virus (HBV) recurrence (11 on HBIg, ten on lamivudine), while three patients became HBsAg-positive. Amongst those without HBV recurrence HBV DNA was detectable only by polymerase chain reaction, intermittently in serum and lymphocytes, and in liver specimens from six of eight patients receiving HBIg and five of seven receiving lamivudine. YMDD variant was found in four cases with no viral antigen expression. Eight patients continued lamivudine after the study and during an additional 6-22 months remained HBsAg-negative with normal graft function. CONCLUSIONS: Substitution of HBIg with lamivudine is effective for prevention of HBV recurrence in low-risk liver transplant recipients and offers a convenient and cost-effective alternative for long-term HBV prophylaxis.     

Acute hepatitis C virus (HCV) infection in chronic carriers of hepatitis B virus (HBV): the impact of underlying active HBV replication on persistence of HCV infection and antibody responses to HCV

BACKGROUND AND AIMS: Liver donors with serological evidence of resolved hepatitis B virus (HBV) infection (HBV surface antigen (HBsAg) negative, anti-HBV core (HBc) positive) can transmit HBV infection to recipients. In the context of organ shortage, we investigated the efficacy of hepatitis B immunoglobulin (HBIG) to prevent HBV infection, and assessed the infectious risk by polymerase chain reaction (PCR) testing for HBV DNA on serum and liver tissue of anti-HBc positive donors. PATIENTS: Between 1997 and 2000, 22 of 315 patients were transplanted with liver allografts from anti-HBc positive donors. Long term HBIG therapy was administered to 16 recipients. Four naive and two vaccinated patients received no prophylaxis. RESULTS: Hepatitis B developed in the four HBV naive recipients without prophylaxis and in none of the vaccinated subjects. Among the 16 recipients receiving HBIG, one patient with residual anti-HBs titres below 50 UI/ml became HBsAg positive. The remaining 15 remained HBsAg negative and HBV DNA negative by PCR testing throughout a 20 month (range 4-39) follow up period. HBV DNA was detected by PCR in 1/22 donor serum, and in 11/21 liver grafts with normal histology. A mean of 12 months post-transplantation (range 1-23) HBV DNA was no longer detectable in graft biopsies from patients remaining HBsAg negative. CONCLUSION: Anti-HBs antibodies may control HBV replication in liver grafts from anti-HBc positive donors, without additional antiviral drugs. These grafts are thus suitable either to effectively vaccinated recipients or to those who are given HBIG to prevent HBV recurrence.     

Genetic alterations in the S gene of hepatitis B virus in patients with acute hepatitis B,chronic hepatitis B and hepatitis B liver cirrhosis before and after liver transplantation

Abstract: Background: Several studies have shown that hepatitis B immunoglobulin (HBIG) imposes a selection pressure on the hepatitis B virus (HBV) S gene, and that the emergence of mutations in this region would make reinfection after orthotopic liver transplantation (OLT) possible. Aims: This study was undertaken to analyze the presence of HBV S-gene mutations in the different stages of HBV infection and the relationship between HBIG therapy and the emergence of mutations in liver transplant recipients. Methods: The frequency and location of mutations in the coding region of the HBV S gene were studied by PCR and direct sequencing in 30 patients (7 with acute self-limited hepatitis B, 16 with chronic hepatitis B and 7 recipients of (OLT) for HBV-related end stage liver disease who became reinfected). Results: The average number of ammo acid changes was higher in patients with a more advanced stage of disease, 0.57 mutations/100 positions in acute hepatitis B and 1.57 in chronic hepatitis B (1.28 in HBeAg-positive and 1.8 in anti-HBe-positive patients). The average number of substitutions in the transplanted patients was 2.7 before OLT and 3 after OLT. No amino acid substitutions were detected in the “a” determinant of HBsAg in acute hepatitis B, however, 8 substitutions were observed in 6 chronic patients. In 3 OLT patients, 4 substitutions were observed in samples before and after OLT. One of these patients, who had protective levels of anti-HBs, showed 3 additional new amino acid substitutions after OLT, suggesting escape mutant selection by the effect of HBIG therapy. No changes were observed between the consensus sequences obtained several years before and after transplantation, indicating consensus sequence stability. Conclusion: These results show that there is an accumulation of HBV S-gene mutations in HBV-related end-stage liver disease. Prophylaxis with HBIG mainly obtained from acute self-limited hepatitis patients who have a highly homogeneous viral population, may be one factor underlying the reinfection after liver transplantation.     

Hepatitis B immunoglobulin discontinuation followed by hepatitis B virus vaccination: A new strategy in the prophylaxis of hepatitis B virus recurrence after liver transplantation

It is widely agreed that hepatitis B virus immunoglobulin (HBIG) should be administered for at least 12 months to patients transplanted for hepatitis B virus (HBV)-related diseases to prevent HBV recurrence. No data are available, however, on how long this treatment should be used, and most centers currently administer HBIG on a life-long basis. Herein, we report the results of a new prophylactic strategy aiming at the discontinuation of HBIG treatment and consisting of the administration of double dose recombinant HBV vaccine (0, 1-, and 6-month schedule) to liver transplant recipients fulfilling the following criteria: (1) liver transplantation for conditions related to nonreplicative HBV infection (hepatitis B surface antigen [HBsAg] positive, hepatitis B e antigen [HBeAg] negative, and HBV DNA negative); (2) at least 18 months of HBIG administration; and (3) no HBV infection recurrence, normal or slightly altered liver graft function, and low-grade immunosuppression at the time of vaccination. Seventeen patients received HBV vaccination and 14 of them (82%) developed protective serum titers of anti-HBs (>10 IU/L). Six patients seroconverted after a first course of vaccination, whereas 8 patients required a second course (3 additional doses of vaccine). Responding patients were followed for a median of 14 months (range, 3-50) after seroconversion. During this period no HBV recurrence occurred and in only 2 patients a decrease of anti-HBs titers below 10 UI/L was observed. Our data suggest that in selected liver transplant recipients, posttransplantation HBV vaccination may be a useful and cost-effective strategy in the prophylaxis of HBV recurrence, allowing the discontinuation of life-long HBIG treatment.     

Hepatitis B surface antigenemia in chronic hemodialysis patients: effect of hepatitis B immunization

OBJECTIVE: Hemodialysis patients with hepatitis B surface antigen (HBsAg) are considered to have the hepatitis B virus (HBV) and are segregated to limit transmission. However, transient de novo HBsAg has been identified in hemodialysis patients shortly after vaccination. Our hypothesis is that immunization rather than actual HBV infection is the most common cause of de novo HBsAg among hemodialysis patients. METHODS: We performed a prospective study between January, 1998 and June, 2000 of de novo HBV infection in over 2400 hemodialysis patients who were screened monthly for HBsAg using a standard enzyme immunoassay. Positive results were confirmed with a neutralization assay. If the confirmatory test was positive, anti-hepatitis B core antibody IgM testing was performed. RESULTS: We identified nine patients with de novo HBsAg confirmed with the neutralization assay. In eight of the nine patients with de novo HBsAg (89%), HBsAg was temporally related to HBV immunization. In none of these eight patients was there a detectable anti-hepatitis B core antibody IgM, an elevated ALT level, or clinical history suggestive of recent hepatitis. The mean age (+/- SD) of the four men and four women was 56.4 +/- 18.8 yr. HBsAg was detectable within 3 days of immunization in most patients. CONCLUSION: Our results suggest that HBV immunization is the most common cause of detectable HBsAg in hemodialysis patients. Hemodialysis patients should not be screened for HBV within a week of immunization, and caution should be exercised when interpreting HBsAg seropositivity within 4 wk of HBV immunization.     

Lamivudine resistance leading to de novo hepatitis B infection in recipients of hepatitis B core antibody positive liver allografts

Most studies have shown that lamivudine (LAM) prophylaxis is sufficient to prevent hepatitis B virus (HBV) transmission in recipients of hepatitis B core antibody positive (HBcAb⁺) allografts. However, de novo hepatitis B (DNHB) is known to occur in this patient population. Herein, we report a case series of four liver transplant recipients who developed DNHB after receiving HBcAb⁺ allografts due to acquisition of LAM resistance mutations, suggesting that LAM prophylaxis may be suboptimal. A retrospective chart review was performed of all adult liver transplants performed at Mount Sinai from 2001 to 2010. A total of 79 patients received HBcAb⁺ allografts for non‐hepatitis B‐related liver disease. Of these 79 recipients, four patients developed DNHB and were found to have documented LAM resistance. With the increasing use of HBcAb⁺ donor livers, we suspect that there will also be a growing number of cases of DNHB due to acquisition of LAM resistance. We suggest that other agents, such as entecavir or tenofovir, be considered for use as prophylaxis in this patient population to decrease this risk.     

Persistence of occult hepatitis B after removal of the hepatitis B virus-infected liver

Occult hepatitis B is defined as the persistence of hepatitis B virus (HBV) DNA in persons without HBV surface antigen (HBsAg). The primary site for HBV persistence in persons with occult hepatitis B is considered to be the liver. We provide virological and immunological evidence for long-term persistence of HBV, even after removal of the infected liver, in 25 consecutive, randomly selected liver transplant recipients who tested positive for anti-HBV core antigen (anti-HBcAg) and negative for HBsAg at the time of transplantation. Furthermore, in a cohort of 101 anti-HBcAg-positive/HBsAg-negative patients, 2 showed clinical HBV reactivation after transplantation. Thus, these data indicate that a long-term extrahepatic HBV reservoir exists, which is relevant not only for liver transplantation but also for other types of transplantations, including bone marrow grafting.