Adefovir therapy for lamivudine escape and hepatitis B virus reactivation after reduced intensity conditioning allogeneic stem cell transplantation

Viral infections in acute graft-versus-host disease: a review of diagnostic and therapeutic approaches

BACKGROUND

While immunosuppressive therapy for acute graft-versus-host disease (aGVHD) advances, viral reactivation has been found to be an increasingly common complication in these patients. Dermatologists may often be consulted on inpatient services for evaluation.

OBJECTIVE

We investigated the literature for the role of viral infections in aGVHD and review the current evidence regarding management.

METHODS

Articles in the public domain regarding aGVHD, cytomegalovirus, Epstein-Barr virus, varicella zoster virus, hepatitis viruses, parvovirus B19, and respiratory viruses were included.

RESULTS

Dermatologic findings vary between different viral antigens, and some infections may be a marker for the development of aGVHD or worsen prognosis.

LIMITATIONS

The heterogeneous cohorts of the studies reviewed often preclude direct comparison between results.

CONCLUSION

The relationship between viral reactivation and aGVHD may be bidirectional and is worthy of further exploration. Additional studies are needed to determine appropriate prophylaxis and treatment.

Risk of hepatocellular carcinoma and cancers at other sites among patients diagnosed with chronic hepatitis B virus infection in Sweden

Hepatitis B virus (HBV) infection is one of most common viral infections worldwide. While chronic HBV infection has been shown consistently to be associated with hepatocellular carcinoma, data on associations with cancers at other sites are limited. In this study a total of 10,197 patients were diagnosed with chronic HBV infection in Sweden, and they were retrieved from the nationwide Swedish Hospital Discharge Register and Outpatient Register and linked to Cancer Registry data. Standardized incidence ratios (SIRs) for cancers were calculated for these patients in comparison with the population without HBV infection. Five hundred sixty-seven of whom developed cancer (SIR 1.82 (95% confidence interval (CI) 1.67-1.97)) during the study period. The SIR for hepatocellular carcinoma in patients with HBV infection was 40.58 (95% CI 30.50-50.07). In addition, a total of seven other cancer sites/types showed increased SIRs: cancers of the upper aerodigestive tract, lung, kidney, skin (squamous cell carcinoma), and thyroid gland, and lymphoma and leukemia. The risks of non-Hodgkin lymphoma and acute myeloid leukemia were increased in both Swedish- and foreign-born patients with HBV infection. In summary, chronic HBV infection is a strong risk factor for hepatocellular carcinoma and also increases the risk of seven other cancers. These findings illustrate the need for surveillance for cancers other than hepatocellular carcinoma in patients with HBV infection.

Adefovir is effective to promote development of immunity to donor origin hepatitis B virus in an allogeneic transplant recipient: a case report

Hepatitis B infection is a serious health problem in endemic areas particularly among immunocompromised patients. The more profound immunosuppression in recipients of hematopoietic stem cell transplantations (HCT) can lead to more complicated hepatitis B virus (HBV)-related events. Despite the high risk of recipient infection allogeneic HCT donors with HBV infection are not excluded in the absence of an alternative donor. A 25 year-old man with severe aplastic anemia underwent allogeneic HCT from his HLA-identical sibling. The patient was hepatitis B naive and had normal liver function tests. However the donor had hepatitis B surface antigen (HbsAg) positivity, and collected stem cells were positive for HBV DNA (1 × 10(4) copies/mL). Lamivudine was initiated to treat the patient prior to transplantation. Forty days after the HCT, the patient displayed hepatitis B surface antibody (HBsAb), hepatitis B core antibody (HBcAb), and hepatitis B e antibody (HBeAb), with HBV-DNA negativity. Cyclosporine was tapered and finally stopped at day + 256. On day +368, 112 days after the cessation of cyclosporine HBV reactivation was detected with an HBV-DNA level of 10 × 10(4) copies/mL despite lamivudine. After demonstration of the YMDD mutation, adefovir dipivoxil was combined with lamivudine. The HBV-DNA became negative; AST ALT levels decreased to normal levels after a month of combination therapy. In conclusion adefovir was effective to treat lamivudine-resistant HBV infection in an allogeneic HCT recipient.

HBV-related events after allogeneic hematopoetic stem cell transplantatıon in a center from Turkey

To investigate the frequency of hepatitis B virus (HBV)-related events after allogeneic HCT in a moderate endemic area for HBV infection. The data of 197 patients who underwent allogeneic hematopoetic stem cell transplatation (HCT) from September 2003 through December 2010 were reviewed retrospectively with respect to HBV-related events. Resolved HBV infection was described as negative HBsAg, positive HBcAb, and positive HBsAb. Latent HBV infection was defined in patients with HBcAb positivity in the abscence of HBV DNA and HBsAb. Hepatitis B naive patients are defined as the patiens with no serological or molecular marker related to HBV. Seropositive patients were the patients with positive HBsAg and HBV-DNA. Median age was 28 (range, 15-64) years, with 128 male and 69 female patients. Median follow-up of the cohort was 8 (range, 0.5-78) months. We detected HBV-related events in 7 (3.6 %) recipients after allogeneic HCT. Five (71.4 %) of these events were HBV reactivation, while two cases (28.6 %) had acute hepatitis B infection. Four of the five reactivations were in the seropositive group (80 %), while one ocurred in a patient with resolved hepatitis. Two patients who developed acute hepatitis B were HBV naive and previously immunized patients, respectively. Hepatitis B virus reactivation remains a problem in seropositive patients and might require more effective treatment strategies.

Hepatitis B virus infection: pathogenesis, reactivation and management in hematopoietic stem cell transplant recipients

Hepatitis B virus (HBV) is a partially double stranded DNA virus that can integrate into host cell chromosomes as covalently closed circular DNA forms. HBV reactivation following hematopoietic stem cell transplantation in recipients with evidence of past HBV exposure, as well as exacerbation of a current HBV infection in HBV carrier recipients, secondary to chemotherapy and post-transplant immunosuppression that affect both humoral and cell-mediated control of HBV infection, are well documented in the literature. Management options include HBV-DNA screening and antiviral prophylaxis. Nucleos(t)ide analogues have been used at the start of chemotherapy and pretransplantation, with the course continuing for 6 months. However, depending on the serum HBV-DNA level, the antiviral agent might be given until a therapeutic end point is reached.

[Current treatment of hepatitis B infection: where do the new nucleos(t)ide analogues fit in?]

One of the most important advances made in the treatment of chronic hepatitis B infection has been the development of nucleos(t)ide analogues. The first antiviral agents used had limited efficacy due to the high resistance rate. However, in the last few years, new agents (tenofovir, entecavir) have been developed with greater antiviral potency and a lower resistance rate. Consequently, these agents are considered to be the treatment of choice in the most recent clinical guidelines. Nevertheless, interferon may still play an important role in the treatment of hepatitis B in selected patients. Moreover, in some contexts, such as renal insufficiency, pregnancy or immunosuppression, the role of the new oral antiviral agents has not been precisely defined. The present review analyzes these aspects, as well as some of the particular features of the management of patients treated with nucleos(t)ide analogues.

Hepatitis B reactivation in patients receiving cytotoxic chemotherapy: diagnosis and management

Nearly one third of the world's population have been infected with hepatitis B and the virus is endemic in many Asian countries. With increasing life expectancy and the expected global increase in cancer, chemotherapy induced reactivation of hepatitis B is likely to become an increasing problem. Patients with significant levels of hepatitis B virus (HBV) DNA in serum prior to chemotherapy and patients receiving intensive chemotherapy for hematological malignancies appear particularly at risk. Most patients who suffer reactivation of hepatitis B are positive for hepatitis B surface antigen (HBsAg) prior to chemotherapy and are therefore easily identifiable by routine screening. In addition, the very large population of patients who have been exposed to the virus and have apparently cleared the virus as assessed by serological testing (HBsAg negative/hepatitis B core antibody [HBcAb] positive) may also be at risk of reactivation. These patients should be monitored and in some cases receive prophylaxis during chemotherapy. Published experience with antiviral prophylaxis has largely been limited to the nucleoside analogue, lamivudine. The commencement of antiviral prophylaxis prior to chemotherapy and its continuation until restitution of normal host immunity is the cornerstone to effective prevention of hepatitis B reactivation. This review summarizes the important issues related to HBV reactivation and suggests an algorithm for managing these patients in the clinical setting.

Prevention and treatment of hepatitis virus infections in hematopoietic stem cell transplant recipients

Infections with Hepatitis viruses B and C pose major problems both short and long term respectively after HSCT. The key to prevention for Hepatitis B disease remains vaccination for HBV-naïve patients and judicial use of anti-viral therapy in both pre- and post-transplant settings for HBV-infected patients. HBsAg positive grafts to HBV-naïve recipients result in transmission of the virus in about 50%. The newer anti-viral agents have enabled effective treatment of post-transplant patients who might be lamivudine-resistant or might develop so. Selecting a previously infected donor who has high titres of surface antibody for HBsAg positive patients gives the best chance for immunological clearance. The most challenging aspect of preventing HBV reactivation remains the duration of anti-viral therapy and timing of its withdrawal as most reactivations and often fatal ones occur after this period. Hepatitis C, on the other hand affects long-term survival with early onset of fibrosis and cirrhosis. Early effect of Hepatitis C virus on the immune system remains conjectural. The standard combination therapy seems to be effective, but data on this front remains sparse, as in the case of the use of newer antiviral agents. HSCT from HCV infected grafts result in more consistent transmission of the virus and pre-donation treatment of donors should be undertaken to render them non-viremic, if possible. The current understanding and recommendations regarding prevention and management of these infections in HSCT recipients are discussed.

Infectious complications of acute and chronic GVHD

Immune defects prolonged by treatment regimens for graft-versus-host disease (GVHD) include cell-mediated immunity and hypogammaglobulinemia. Infections have become increasingly important during GVHD therapy, paradoxically because the success of immunosuppressive practice has led to improved survival. Infections originate from both endogenous and exogenous sources. Regimens for prevention of infection include: (a) continued surveillance monitoring for infections with reliable diagnostic testing, and (b) antimicrobial prophylaxis for those pathogens without markers that could be followed for surveillance. Repeated episodes of the same infection, diagnosis of a new life-threatening infection, or specific underlying hematologic diagnoses should prompt a look for gross immunoglobulin deficiency that could be corrected in the short term by immunoglobulin therapy. At times, measurement of CD4+ lymphocyte counts will assist in determining whether augmented prophylaxis is warranted. Since their efficacy may be limited, vaccine injections are not given during the immunosuppression associated with GVHD therapy, with the exception of influenza.

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 prophylaxis in patients undergoing chemotherapy for lymphoma: a decision analysis model

Hepatitis B reactivation is a major cause of morbidity and mortality in patients undergoing chemotherapy for lymphomas. These patients may experience direct liver-related complications or reduced cancer survival because of interruptions in chemotherapy. Our aim was to compare the costs and outcomes of 2 different chronic hepatitis B management strategies. In hepatitis B carriers undergoing chemotherapy, we pursued a decision analysis model to compare the costs and clinical outcomes of using lamivudine prophylaxis versus initiating lamivudine only when clinically overt hepatitis occurred. Our results indicate that the use of lamivudine prophylaxis is cost-effective. Even though the use of lamivudine prophylaxis was associated with an incremental cost of $1530 per patient ($18,707 versus $17,177), both the number and severity of hepatitis B reactivations were reduced. None of the patients in the prophylaxis group had liver-related deaths versus 20 who died in the no-prophylaxis group. Cancer deaths were also reduced from 47-39 with lamivudine prophylaxis, presumably because of the increased need for cessation or modification of chemotherapy in patients who had severe hepatitis B virus flares. The incremental cost-effectiveness ratio of using lamivudine prophylaxis was $33,514 per life year saved.

CONCLUSION

Our results provide pharmacoeconomic support for the use of lamivudine prophylaxis in patients undergoing chemotherapy for lymphoma treatment.

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.

Hepatitis B virus reactivation in breast cancer patients receiving cytotoxic chemotherapy: a prospective study

Breast cancer is a rapidly increasing problem in many developing countries, and cytotoxic chemotherapy is now an integral part of its management. In several developing countries, the carriage of hepatitis B virus (HBV) in cancer patients may be as high as 12%, and such patients are at risk of developing fatal HBV reactivation during chemotherapy. HBV reactivation is well recognized in patients with hematological malignancies, but limited data are available on patients with other, more common, cancers, such as breast cancer. Recent data have suggested that increased viral replication, an indication of HBV reactivation, may precede clinical hepatitis. In the absence of serial HBV DNA monitoring, HBV reactivation during chemotherapy may have been underestimated. In this prospective study, breast cancer patients who were hepatitis B surface antigen (HBsAg) seropositive were followed up during chemotherapy. The main objectives were to determine the incidence of HBV reactivation in breast cancer patients undergoing conventional chemotherapy; to investigate whether "serial HBV DNA monitoring" improves the accuracy of diagnosing HBV reactivation when compared with previous schema that only measured HBV DNA at the time of clinical hepatitis ("conventional monitoring"); and to assess the clinical consequences as a result of developing the condition. The secondary objective was to identify risk factors associated with this condition. Over an 18-month period, 41 patients were studied. Ten developed HBV reactivation by conventional monitoring criteria, but with serial HBV DNA monitoring, seven additional patients were diagnosed when increased HBV DNA levels were detected before, but not concomitant with, clinical hepatitis. Thus, a total of 17 patients (41%) developed HBV reactivation. Premature termination of chemotherapy or delay in treatment schedules occurred in 71% of the patients who developed viral reactivation, as compared with 33% in those who did not develop the condition (P = 0.019). No risk factors associated with the development of HBV reactivation could be identified. Serial monitoring of HBV DNA, in addition to liver function, increases the sensitivity of diagnosing of HBV reactivation, and helps explain some cases that would otherwise be labeled as "cryptogenic hepatitis," for which concomitant HBV DNA measured at the time of hepatitis was undetectable. The present study highlights the importance of monitoring HBsAg-seropositive patients who are receiving chemotherapy for common solid tumors such as breast cancer.