Hepatitis B exacerbation with a precore mutant virus following withdrawal of lamivudine in a human immunodeficiency virus-infected patient

Hepatitis B virus (HBV) reactivation-The potential role of direct-acting agents for hepatitis C virus (HCV)

Hepatitis C virus (HCV) is known to inhibit hepatitis B virus (HBV) replication in patients with HBV/HCV coinfection. Reactivation of HBV in patients treated for HCV with direct-acting agents (DAAs) has emerged recently as an important clinical consideration. A growing number of case reports and case series support the association between new HCV treatments and HBV reactivation. Yet, very little is known about the specific viral characteristics that facilitate reactivation as functional characterization of the reactivated HBV has been conducted only rarely. This review provides the most recent data on HBV reactivation in the context of DAA initiation and highlights the existing viral genomic data from reactivating viruses. Current functional studies of HBV reactivation are largely limited by the retrospective identification of cases, no standardization of genomic regions that are studied with respect to HBV reactivation, and the lack of inclusion of nonreactivating controls to establish specific viral mutations that are associated with HBV reactivation. Importantly, none of these sequencing studies included cases of HBV reactivation after initiation of DAAs. While new HCV treatments have revolutionized care for HCV infected patients, HBV reactivation will likely increase in frequency, as DAAs are more commonly prescribed. Pretreatment determination of HBV status and thoughtful management of HBV coinfections will be necessary and lead to improved patient safety and yield optimal treatment results.

Genetic variation of hepatitis B virus and its significance for pathogenesis

Hepatitis B virus (HBV) has a worldwide distribution and is endemic in many populations. Due to its unique life cycle which requires an error-prone reverse transcriptase for replication, it constantly evolves, resulting in tremendous genetic variation in the form of genotypes, sub-genotypes, and mutations. In recent years, there has been considerable research on the relationship between HBV genetic variation and HBV-related pathogenesis, which has profound implications in the natural history of HBV infection, viral detection, immune prevention, drug treatment and prognosis. In this review, we attempted to provide a brief account of the influence of HBV genotype on the pathogenesis of HBV infection and summarize our current knowledge on the effects of HBV mutations in different regions on HBV-associated pathogenesis, with an emphasis on mutations in the preS/S proteins in immune evasion, occult HBV infection and hepatocellular carcinoma (HCC), mutations in polymerase in relation to drug resistance, mutations in HBV core and e antigen in immune evasion, chronicalization of infection and hepatitis B-related acute-on-chronic liver failure, and finally mutations in HBV x proteins in HCC.

Spontaneous reactivation of hepatitis B virus replication in an HIV coinfected patient with isolated anti-Hepatitis B core antibodies

Co-infections with HBV (hepatitis B virus) occur in HIV (human immunodeficiency virus) patients frequently. It has been reported that an effective treatment of HIV can also lead to a suppression of HBV and to anti-HBs seroconversion in HBV-infected patients. Here, we report a spontaneous reactivation of HBV replication in an HIV-infected patient with anti-HBc as the only marker of chronic HBV infection. The patient was known to be coinfected with HIV and HBV for years and the HBV DNA was measured repeatedly at low levels. A significant increase of HBV DNA up to 1.7x10⁷ IU/ml was found accompanied with clinical symptoms of hepatitis. Multiple mutations occurred in the S gene during the flare-up of HBV as shown by sequencing, including I103T, K122R, M133I, F134V, D144E, V164E and L175S. Anti-HIV/HBV treatment led to a resolution of symptoms and to a decrease in the HIV RNA and HBV DNA viral load. It is possible that the accumulated mutations during HBV replication were selected and responsible for the reactivation.

Management of HIV and hepatitis virus coinfection

IMPORTANCE OF THE FIELD

Liver disease related to infection with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) is a frequent cause of morbidity and mortality in those infected with the human immunodeficiency virus (HIV) in this era of highly active antiretroviral therapy (HAART). Although progress has been made in the treatment of HBV and HCV in the setting of HIV-coinfection, there is a lack of data in certain areas and several aspects of the management are unclear at this time.

AREAS COVERED IN THIS REVIEW

Available data on the treatment of HBV and HCV infections, especially in the HIV-coinfected patient, are presented. Practical aspects of the management of these patients are reviewed, including diagnosis, treatment indications, monitoring, and toxicities. The impact of HAART on liver disease, end-stage-liver disease, and new therapeutic approaches are also reviewed.

WHAT THE READER WILL GAIN

There are two modalities for the treatment of chronic HBV infection: interferon and nucleos(t)ide reverse transcriptase inhibitors (NRTI). The latter is the mainstream of therapy for HIV-HBV-coinfected patients. The double antiviral activity of NRTI requires coordination and careful selection of treatment for both viruses to avoid selection of resistance mutations and toxicity. Combination of pegylated interferon and ribavirin, the current standard treatment for chronic hepatitis C, has significant toxicity and limited efficacy in HIV-HCV-coinfected individuals. Oral anti-HCV treatments are currently under development and need to be studied in the HIV-coinfected population. Liver transplantation has a better outcome in HBV- than in HCV-HIV-coinfected patients. HAART seems to have a positive impact on the liver disease of HBV- and/or HCV-coinfected subjects but the CD4 threshold above which the benefit might take place is unknown at this time.

TAKE HOME MESSAGE

Anti-HBV treatment in the HIV-coinfected patient relies on the available NRTIs with activity against both viruses. Whereas HBV suppression can be achieved with this approach, toxicities and the selection of HBV-resistant variants result in challenging clinical scenarios. Current anti-HCV treatment (pegylated interferon and ribavirin) has limited efficacy in the HIV-coinfected patient, and STAT-C drugs are eagerly awaited.

Frequent hepatitis B virus rebound among HIV-hepatitis B virus-coinfected patients following antiretroviral therapy interruption

BACKGROUND

The impact of antiretroviral therapy (ART) interruption in HIV-hepatitis B virus (HBV)-coinfected patients was examined in the Strategic Management of AntiRetroviral Therapy (SMART) study.

METHODS

Plasma HBV DNA was measured in all hepatitis B surface antigen-positive (HBV-positive) participants at baseline, and at months 1, 2, 4, 6, 8, 10, and 12.

RESULTS

Among HBV-positive participants in the ART interruption (drug conservation) (n = 72) and ART continuation (virological suppression) (n = 62) arms, HBV DNA rebound of more than 1 log from baseline at months 1-4 was seen in 31-33% (P = 0.003) and 3-4% (P = 0.017), respectively. Thirteen HBV-positive participants had HBV DNA rebound of more than 3 log, including 12 in the drug conservation arm, of which eight were on tenofovir-containing regimens. Factors independently associated with a HBV DNA rebound were drug conservation arm (P = 0.0002), nondetectable HBV DNA at baseline (P = 0.007), and black race (P = 0.03). Time to ART reinitiation was shorter (7.5, 15.6, and 17.8 months; P < 0.0001) and proportion reinitiating greater (62.5, 46.5, and 39.7%; P = 0.0002) among HBV-positive participants as compared with hepatitis C virus-positive and non-HBV/hepatitis C virus participants in the drug conservation arm. No hepatic decompensation events occurred among HBV-positive participants in either arm.

CONCLUSION

HBV DNA rebound following ART interruption is common and may be associated with accelerated immune deficiency in HIV-HBV-coinfected patients.

Hepatitis B in the HIV-Coinfected Patient

HIV and hepatitis B virus (HBV) infection share transmission patterns and risk factors; therefore, it is not surprising that the prevalence of chronic HBV infection is elevated among HIV-infected persons. HBV does not significantly affect the course of HIV disease, but HIV does alter the course of HBV. HIV-infected persons are less likely to clear acute HBV infection spontaneously, and HIV/HBV-coinfected persons face a higher risk of liver-related death than those monoinfected with either virus. The immune restoration associated with highly active antiretroviral therapy (HAART) can improve control of HBV replication but can also lead to increased immune-mediated liver injury. On balance, use of HAART before severe immunosuppression develops may be beneficial. Still, the complexity of HBV, HIV, and HAART interactions must be evaluated for each individual. There is a dearth of high-quality evidence about management of coinfected patients. A recent consensus conference has issued recommendations. HBV DNA thresholds for starting anti-HBV therapy are the same in coinfected and HBV-monoinfected patients. Continuing drugs with anti-HBV activity is important, because stopping such therapy has been associated with HBV reactivation. Development of resistance is a risk with the long-term maintenance therapy required in most patients.

Do HIV care providers appropriately manage hepatitis B in coinfected patients treated with antiretroviral therapy?

BACKGROUND

The common occurrence of hepatitis B virus (HBV) infection in patients who carry the human immunodeficiency virus (HIV) demands that both viruses be recognized, evaluated, and treated when appropriate.

METHODS

We identified 357 HIV- and hepatitis B surface antigen-positive patients who underwent testing from 1999 to 2003; 155 patients who were new to our clinic and who initiated therapy for HIV and HBV coinfection were considered for inclusion in the study. The frequency of HIV testing (to determine HIV load and CD4+ cell count) performed during the first year of therapy was compared with the frequency of HBV measurements (to determine hepatitis B e antigen, antibody to hepatitis B e antigen, and HBV load), abdominal ultrasound examination, and measurement of levels of alpha-fetoprotein in serum.

RESULTS

HBV load data were obtained for only 16% of patients before initiation of antiretroviral therapy (ART), whereas HIV load was determined for 99% of patients before initiation of ART. The total number of HIV load measurements obtained during the first year after ART initiation was 497 (median number of HIV load measurements per patient, 3.0), compared with 85 measurements of HBV load (median number of HBV load measurements per patient, <1; P<.001). The percentage of patients who received any level of HBV monitoring (i.e., tests to determine hepatitis B e antigen, antibody to hepatitis B e antigen, and HBV load) after ART initiation increased from 7% in 1999 to 52% in 2001 (P<.001), whereas the percentage of patients who underwent HIV load testing remained at 80%-90% during the same period.

CONCLUSIONS

Health care providers treating patients with HIV infection during the period 1999-2003 infrequently monitored HBV response in coinfected patients, but they systematically monitored HIV response after ART initiation. Improved physician adherence to guidelines that better delineate HBV treatment and monitoring for patients with HIV-HBV coinfection is needed.

HIV-related liver disease: infections versus drugs

HIV-infected individuals have myriad causes of hepatotoxicity that range from mild hepatitis to significant liver failure with its associated morbidity and mortality, especially in the setting of chronic viral hepatitis (HCV and HBV). Immune restoration by HAART therapy can contribute liver-related toxicity in HIV-coinfected patients. Clinicians need to be aware of this problem and individualize management in this challenging clinical scenario. Avoidance of potentially hepatotoxic agents or close monitoring during treatment of HIV may prevent liver failure in patients who have HIV. Furthermore, vaccination against hepatitis A virus and HBV in nonimmune HIV individuals may prevent acquisition of hepatitis A virus and HBV infections in patients who have HIV. Finally, treatment of HIV, and, if appropriate, treatment of those who are coinfected with HCV and HBV with close monitoring, may improve the outcome of patients who have HIV and are at risk fo r significant hepatotoxicity during treatment from immune restoration or hypersensitivity reactions.

Treatment options in HBV

The available evidence on interferon-alpha (IFN) treatment for chronic hepatitis B is sufficient to conclude that in patients with HBeAg positive chronic hepatitis, standard IFN therapy significantly improves clearance of HBeAg (number needed to treat [NNT] = 4), loss of HBV-DNA (NNT = 4) and clearance of HBsAg (NNT = 18). HBeAg positive patients with normal or slightly raised ALT should be treated only if there is histological evidence of progressive disease. In patients with HBeAg negative chronic hepatitis, less than 20% of subjects who have achieved an end-of-treatment virological response after a course of standard IFN maintain a sustained virological response in the long-term. IFN treatment could help to delay or prevent disease decompensation and liver-related deaths but further large studies are needed. Lamivudine is effective at reducing, and sometimes clearing, HBV replication in heavily immunosuppressed patients and can be safely administered to patients with advanced liver disease. Lamivudine should be continued over an undefined extended period of time, with a switch from lamivudine to adefovir if there is an HBV-DNA breakthrough under therapy. Adefovir, excluding cost, is preferable to lamivudine as a first-choice because there is less chance of inducing resistance. The long-term benefit of lamivudine and adefovir and the role of combinations is under investigation.

Natural history of chronic hepatitis B in co-infected patients

HIV co-infection influences the course and natural history of hepatitis B virus (HBV) infection by impairing the quantity and quality of the innate and adaptive immune response. The rates of spontaneous resolution after acute infection and spontaneous anti-HBe and anti-HBs seroconversions are decreased, and levels of HBV replication are increased in HIV-infected patients. A more rapid progression of liver fibrosis and a higher rate of cirrhosis decompensation (but not hepatocellular carcinoma) have been demonstrated in co-infected patients. The risk of HBV-associated end-stage liver disease and liver-related mortality may be increased by HIV co-infection. Antiretroviral therapy may trigger spontaneous anti-HBe and anti-HBs seroconversion and/or a better immune control of HBV replication by restoring adaptive immunity, but can also increase hepatitis flares. Reactivation of chronic hepatitis B has been observed after suspension of anti-retrovirals with anti-HBV activity or after occurrence of HBV resistance to lamivudine. Future research should focus on: the impact of HIV-induced changes in innate and adaptive immune response and modifications induced by anti-retroviral therapy that may impact on progression of advanced chronic hepatitis B; the association between HBV genotype and clinical course of disease; and the role of occult HBV infection as a co-factor with other causes of liver injury.

Complications in treating chronic hepatitis B in patients with HIV

The management of chronic hepatitis B virus (HBV) poses specific problems in the presence of HIV infection, as therapeutic approaches have to consider both HBV and HIV. There are currently four drugs approved for the treatment of chronic HBV: IFN-alpha, lamivudine, adefovir and entecavir. Furthermore, the dual antiviral activity against HIV and HBV of antiretrovirals such as tenofovir and emtricitabine broadens the armamentarium against HBV in the HIV-coinfected population. Nucleotide analogues adefovir and tenofovir have the advantage of a higher genetic barrier for resistance when compared with the nucleoside analogues lamivudine and emtricitabine. Fortunately, the two families do not share resistance mutations, allowing salvage therapy and the consideration of combination therapy for drug-naive individuals. Although response to IFN-alpha is poorer in HBV/HIV-coinfected patients compared with HBV-monoinfected individuals, the more potent pegylated forms of IFN-alpha have brought new hopes.

Reactivation of hepatitis B in an HIV-infected patient with antibodies against hepatitis B core antigen as the only serological marker

Presented here is the first report of clinical reactivation of hepatitis B virus (HBV) in an HIV-infected patient who previously had anti-HBc as the only serological marker of past infection (anti-HBc alone). Reactivation occurred after lamivudine was removed from the patient's antiretroviral treatment regimen due to lack of virological response. HIV-infected patients frequently present anti-HBc alone, and in some cases this serological profile is associated with occult HBV infection. The current case demonstrates the importance of ruling out the possibility of occult infection in this patient group.

Management of patients co-infected with hepatitis B virus and HIV

The management of chronic hepatitis B virus (HBV) infection poses specific problems in the presence of HIV co-infection, since therapeutic approaches have to consider both HBV and HIV infections. There are currently four drugs approved for the treatment of chronic HBV infection (interferon alpha, lamivudine, adefovir, and entecavir); the dual antiviral activity of tenofovir and emtricitabine broadens the armamentarium against HBV in HBV/HIV co-infected patients. Nucleotide analogues--eg, adefovir and tenofovir--have the advantage of a higher genetic barrier to the development of resistance compared with nucleoside analogues--eg, lamivudine and emtricitabine. Fortunately, the two families do not share resistance mutations, allowing salvage therapy and the possibility of combination therapy for drug-naive individuals. Although response to interferon alpha is poorer in HBV/HIV co-infected patients compared with HIV-negative individuals, especially in hepatitis B e antigen-negative HBV infection, the more potent pegylated forms of interferon alpha have brought new hope.

Hepatitis B virus variants in an HIV-HBV co-infected patient at different periods of antiretroviral treatment with and without lamivudine

Background

Lamivudine inhibits replication of both human immunodeficiency virus (HIV) and hepatitis B virus (HBV) and is commonly used as part of antiretroviral therapy. The main limitation in the use of lamivudine is resistant mutation selection. Most of these mutations affect the YMDD motif of the HBV DNA polymerase. The resistance occurs through M550V or M550I aminoacid replacements. The M550V variation may be accompanied by L526M mutation, notably in HIV-HBV co-infected patients. The aim of this study was to investigate mutations associated with lamivudine resistance in a hemodialysis patient chronically co-infected with HIV-1 and HBV, who was submitted to several antiretroviral treatments.

Methods

HBV isolates derived from three blood samples collected at different times of antiretroviral therapies with and without lamivudine, were titred and submitted to nucleotide sequencing.

Results

HBV isolate derived from a sample collected in 1999 during an antiretroviral treatment with lamivudine showed the lamivudine resistant double mutation (L526M, M550V). However, no mutation associated with lamivudine resistance was observed in the HBV genome derived from the sample collected during a period of treatment without lamivudine (2001). After reinstitution of lamivudine (2002), the predominant HBV population exhibited a rare triple mutation (V519L, L526M, M550V), which has previously been associated with an in vitro reduction of virus antigenicity (escape mutant). HBV DNA was detected at high levels (10⁸–10⁹ copies/ml) in the three blood samples.

Conclusions

Reintroduction of lamivudine as part of antiretroviral treatment in a patient who had developed lamivudine resistant HBV strains favored the predominance of an HBV isolate with reduced antigenicity. The absence of hepatitis acute exacerbation in this patient may be correlated to the absence of significant variations of the viral load, which was independent of the presence of mutations in the HBV DNA polymerase.

Treatment of chronic hepatitis B in the human immunodeficiency virus-infected patient: present and future

The management of chronic hepatitis B poses specific problems in the presence of human immunodeficiency virus (HIV) coinfection, because therapeutic approaches have to address both hepatitis B virus (HBV) and HIV infections. Response to interferon (IFN-alpha) is lower in HBV-HIV-coinfected than in HIV-negative subjects, especially in patients in advanced stages of immunosuppression. Thus far, there are no data on the performance of the new pegylated forms of IFN-alpha in HBV- and HIV-coinfected persons. After prolonged use of lamivudine, resistance develops in the majority of HBV-HIV-coinfected patients treated with the drug. The more recently approved tenofovir has shown excellent short-term results, and data from longer follow-up studies are eagerly awaited. Several drugs with combined anti-HIV and anti-HBV activity have recently been approved (emtricitabine) or are currently under development. Preliminary results with some of them are quite promising and probably will widen the therapeutic armamentarium against hepatitis B in patients with HIV infection.

Prevalence and characterization of lamivudine-resistant hepatitis B virus mutations in HIV-HBV co-infected individuals

OBJECTIVE

To determine the prevalence of hepatitis B virus (HBV) genotypic resistance to lamivudine, identify risk factors associated with lamivudine resistance, and characterize the pattern of HBV polymerase mutations in patients co-infected with HIV.

DESIGN

Retrospective cross-sectional study.

METHODS

Thirty-three chronic HBV-infected patients were identified from a cohort of 1719 HIV-infected individuals. Patient information was collected from case records, HBV DNA was measured on stored serum by polymerase chain reaction, and positive samples underwent sequencing of HBV polymerase, basal core promoter and precore regions.

RESULTS

Three groups of patients were identified: group 1 were viraemic in the absence of lamivudine-resistance mutations, group 2 were viraemic in association with lamivudine-resistance mutations, and group 3 were not viraemic. Group 2 patients with lamivudine-resistant mutations had significantly higher HBV-DNA viral loads but did not differ in duration of lamivudine therapy, HBV genotype, HIV viral load or CD4 cell count compared with patients with wild-type HBV. Group 2 individuals also demonstrated significantly higher serum alanine aminotransferase (ALT) levels than group 1, who were higher than group 3. Unique mutations were detected in HBV polymerase, including rtV173L plus rtL180M plus rtM204V, which occurred in three patients. This virus has the in-vitro characteristics of a 'vaccine escape' mutant of HBV.

CONCLUSION

Genotypic HBV lamivudine resistance was found in 39% of HIV-HBV co-infected individuals treated with lamivudine as part of highly active antiretroviral therapy. These patients exhibited significantly elevated HBV viral loads and serum ALT, and three were infected with a lamivudine-resistant HBV strain that was potentially transmissible to HBV-vaccinated individuals.

Management of chronic viral hepatitis in HIV-infected patients: Spanish Consensus Conference. October 2000

Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed.