Fibrosing cholestatic hepatitis after liver transplantation in a patient with hepatitis C and HIV infection

Cholestatic hepatitis C following liver transplantation: an outcome-based histological definition, clinical predictors, and prognosis

Cholestatic hepatitis C virus (HCV) is a rare form of recurrent HCV following liver transplantation (LT) without specific diagnostic criteria. An outcome-based method to improve its diagnosis and a description of its prognosis are needed. All 1-year post-LT protocol liver biopsy samples and biopsy samples initially reported to show cholestatic HCV from patients transplanted with HCV between February 2002 and December 2009 were reviewed for the inflammation grade, the fibrosis stage, and 4 cholestatic HCV features: ductular proliferation, canalicular cholestasis with or without intracellular cholestasis, hepatocyte swelling with or without lobular disarray, and sinusoidal/pericellular fibrosis. We used patient and graft survival to define histological criteria for cholestatic HCV, and compared the clinical features of these patients to those of patients with minimal or significant post-LT fibrosis. One hundred seventy-nine patients were analyzed, the median age was 56 years, and 73% were male. Patients with 3 or more of the 4 cholestatic HCV criteria had significantly worse survival (log-rank P < 0.001) regardless of the fibrosis stage, and this was used as our novel definition of cholestatic HCV. Using this definition, we found that 27 patients (15%) had cholestatic HCV, 53 (30%) had significant fibrosis (stage ≥ 2/4), and 99 (55%) had minimal fibrosis (stage < 2/4). The final model for clinical predictors of cholestatic HCV included donor age [odds ratio (OR) = 1.37 per decade, P = 0.04] and previous rejection (Banff grade ≥ 5; OR = 4.19, P = 0.002). Total bilirubin was the strongest laboratory predictor of cholestatic HCV (area under the curve = 0.93), whereas the HCV viral load was not a significant predictor. The final model of post-LT survival included the pathology group {cholestatic HCV [hazard ratio (HR) = 6.07, P < 0.001] and significant fibrosis (HR = 2.53, P = 0.02)}, donor age (HR = 1.49 per decade, P < 0.001), and cold ischemia time (HR = 1.11 per hour, P = 0.02). In conclusion, we propose diagnostic criteria for cholestatic HCV that include specific criteria (the presence of at least 3 of the 4 histopathological features on biopsy) and other supportive and exclusionary criteria. Older donor age and rejection increase the risk of cholestatic HCV, and an elevation in the total bilirubin level may help to identify these patients. These criteria must be validated prospectively.

Liver transplant outcomes in HIV-infected patients: a systematic review and meta-analysis with synthetic cohort

OBJECTIVES

The relative success of liver transplantation in those with HIV compared to HIV-uninfected individuals remains a point of intense debate. We aimed to evaluate the effectiveness of liver transplantation in HIV-hepatitis co-infected patients using a meta-analysis and individual patient data meta-analysis as a synthetic cohort.

METHODS

We searched MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE (inception to 2010), AMED, CINAHL, TOXNET, Development and Reproductive Toxicology, Hazardous Substances Databank, Psych-info and relevant conferences. We included cohort studies and individual case-reports evaluating survival of co-infected transplant patients. We abstracted data on cohort and case demographics and outcomes. We pooled cohorts using a random-effects analysis and created a synthetic cohort of cases using individual patient data. We confirmed this with the pooled cohort analysis.

RESULTS

We included 15 cohort studies and 49 case series with individual patient data. At 12 months, 84.4% [95% confidence interval (CI) 81.1-87.8%] of patients had survived. Within the HIV-infected population evaluated, HIV-hepatitis B virus (HBV) co-infection was associated with optimal survival. In an adjusted model, individuals positive for HBV were 8.28 (95% CI 2.26-30.33) times more likely to survive when compared to those without HBV. Further, individuals with an undetectable HIV viral load at the time of transplantation were 2.89 (95% CI 1.41-5.91) times more likely to survive when compared to those with detectable HIV viremia. Hepatitis C virus was not a predictor of patient survival when adjusted for by other key predictors [0.54 (95% CI 0.17-1.80)].

Post-liver transplant cholestatic hepatitis C: a systematic review of clinical and pathological findings and application of consensus criteria

Liver transplantation is currently the only definitive modality for the treatment of end-stage liver disease due to chronic hepatitis C. However, recurrent hepatitis C after liver transplantation is nearly universal. Cirrhosis may develop in 20% of recipients within 5 years, and recurrent hepatitis C may lead to graft failure, retransplantation, and even death. A subset of recipients may develop post-liver transplant cholestatic hepatitis C (PLTCHC), which is characterized by cholestasis, hepatocyte ballooning, and rapid progression to graft failure. We present a systematic review of PLTCHC that is focused on hepatitis C-infected liver transplant recipients. We compare the pathological definitions of PLTCHC, clinical factors, management strategies, and outcomes reported in studies. We found differences among studies in the types of histological criteria used to diagnose PLTCHC during liver biopsy and in the types of clinical information provided. Three of the 12 studies published after 2003 used the definition of PLTCHC published by the first International Liver Transplantation Society expert panel consensus conference on liver transplantation and hepatitis C. We propose that studies on PLTCHC use the consensus criteria for diagnosis and suggest clinical information that should be provided in future studies with the goal of improving our understanding and management of this deadly disease.

Liver transplant in patients with HIV: infection risk associated with HIV and post-transplant immunosuppression

Before the introduction of highly active antiretroviral therapy, HIV-infected patients who underwent liver transplantation (LT) had poor survival, mainly because of a rapid progression to AIDS and its infectious complications during the post-LT immunosuppression phase. However, in the era of highly active antiretroviral therapy, under some specific and well-determined conditions, LT might be as safe and efficacious in HIV patients as it is in non-HIV-infected patients. End-stage liver failure as caused by hepatitis B virus, cirrhosis, and hepatotoxicity should be considered indications for LT in every transplant center. Because of the almost universal hepatitis C virus reinfection and its accelerated course post-LT, LT in hepatitis C virus-coinfected patients deserves more caution and more extended follow-up before it is accepted as a standard indication for LT in HIV-infected patients.

Ethical and scientific issues surrounding solid organ transplantation in HIV-positive patients: Absence of evidence is not evidence of absence

End-stage liver disease is emerging as a leading cause of death among HIV-positive patients. Historically, an HIV diagnosis was a contraindication for a liver transplant; however, because of the efficacy of highly active antiretroviral therapy (HAART), HIV-positive patients have one-year, two-year, and three-year post-transplantation survival rates similar to that of HIV-negative patients. Based on this evidence, HIV-positive patients are now considered eligible for transplantation. However, newly emerging guidelines include the stipulation that HIV-positive patients must be on HAART to be placed on a waiting list for transplantation. The purpose of the present paper is to evaluate the scientific and ethical probity of requiring HIV-positive patients to be on HAART as a condition for being on a liver transplant waiting list. It is argued that the emphasis should be placed on the probability of post-transplantation HAART tolerance, and that concerns about pretransplantation HAART tolerance are of secondary importance.

Barriers preventing liver transplantation in Canadians with HIV-infection--perceptions of HIV specialists

Liver transplantation is a life-saving procedure with demonstrated utility. There are accumulating data indicating that this procedure is helpful in HIV-infected patients as well. Liver transplantation is currently largely unavailable to those living with HIV in Canada. Understanding the obstacles to this procedure is the first step to increasing access. Between August 2005 and November 2005, HIV physicians, one from each Canadian HIV Trials Network site, were asked to complete a quantitative questionnaire on adult liver transplant access and need. Forty-six per cent (16 of 35) of sites responded. A median 20% of the nearly 12,700 HIV patients followed at these sites had concurrent liver disease (20% caused by hepatitis C virus, 5% caused by hepatitis B virus and 5% were alcohol-related). On average, two patients per site were thought to be appropriate candidates for liver transplant evaluation. Eighty per cent of respondents anticipated increased need for liver transplantation over the next five years. Organ supply was universally identified as the chief obstacle to transplantation in patients with HIV. Other key issues included risk of hepatitis C virus reinfection and transplant surgical team willingness. Based on these data, it is believed that these issues should be the focus of efforts designed to increase access to transplantation in Canadians with end-stage liver disease and concurrent HIV.

HIV/HCV co-infection: histopathologic findings, natural history, fibrosis, and impact of antiretroviral treatment: a review article

Human immunodeficiency virus/hepatitis C virus (HIV/HCV) co-infection has emerged as a leading cause of liver morbidity in the last two decades. Liver failure is also frequently a cause of death in HIV/HCV co-infected patients. Highly active antiretroviral treatment (HAART) has revolutionized the HIV treatment, leading to a significantly decreased morbidity, prolonged survival, and an overall better outcome of HIV infection. Hepatotoxicity associated with antiretroviral treatment, however, has been recognized as one of the serious complications of the treatment. The effects of HIV infection on the natural history and progression of HCV-associated chronic liver disease that had been well documented in the pre-HAART treatment era have been changing, and there are now many indications that HIV/HCV co-infection should be recognized as an evolving and a challenging disease entity.

Survival of liver transplant patients coinfected with HIV and HCV is adversely impacted by recurrent hepatitis C

Although liver transplantation (LTx) in HIV-positive patients receiving highly active antiretroviral therapy (HAART) has been successful, some have reported poorer outcomes in patients coinfected with hepatitis C virus (HCV). Here we discuss the impact of recurrent HCV on 27 HIV-positive patients who underwent LTx. HIV infection was well controlled post-transplantation. Survival in HIV-positive/HCV-positive patients was shorter compared to a cohort of HIV-negative/HCV-positive patients matched in age, model for end-stage liver disease (MELD) score, and time of transplant, with cumulative 1-, 3- and 5-year patient survival of 66.7%, 55.6% and 33.3% versus 75.7%, 71.6% and 71.6%, respectively, although not significantly (p = 0.07), and there was a higher likelihood of developing cirrhosis or dying from an HCV-related complication in coinfected subjects (RR = 2.6, 95% CI, 1.06-6.35; p = 0.03). Risk factors for poor survival included African-American race (p = 0.02), MELD score > 20 (p = 0.05), HAART intolerance postLTx (p = 0.01), and postLTx HCV RNA > 30000000 IU/mL (p = 0.00). Recurrent HCV in 18 patients was associated with eight deaths, including three from fibrosing cholestatic hepatitis. Among surviving coinfected recipients, five are alive at least 3 years after LTx, and of 15 patients treated with interferon-alpha/ribavirin, six (40%) are HCV RNA negative, including four with sustained virological response. Hepatitis C is a major cause of graft loss and patient mortality in coinfected patients undergoing LTx.

Natural history and predictors of severity of chronic hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection

Co-infection by the hepatitis C virus (HCV) is observed in up to 30% of HIV-infected individuals. In studies conducted in the 'pre-HAART era', the late consequences of HCV-related chronic liver disease were overshadowed by extra-hepatic causes of deaths, related to severe immune deficiency, and the impact of HCV infection on mortality of HIV-infected patients was low. While the development of HAART has resulted in a significant decrease in morbidity and mortality amongst HIV-infected patients, this clear benefit allowed the expression of liver-related complications associated with HCV chronic infection. The impact of HCV on HIV remains debated but HIV infection significantly modifies the natural history of HCV infection. HIV infection increases levels of HCV viraemia by 2- to 8-fold, resulting in a significant decrease in spontaneous recovery of acute hepatitis. HIV co-infection also worsens the histological course of HCV infection by increasing and accelerating the risk of cirrhosis or leading to rare but lethal fibrosing cholestatic hepatitis. Liver disease is now one of the leading causes of morbidity and mortality in co-infected patients, even if HAART and especially protease inhibitors, may decrease the severity of the liver disease and the liver-related mortality. Several non-exclusive pathogenic processes explain the increasing rate of liver complications associated with HCV-related liver disease.

Liver histopathology in human immunodeficiency virus-hepatitis C virus co-infected patients with fatal liver disease

BACKGROUND

Liver failure is an increasing cause of death in human immunodeficiency virus-hepatitis C virus (HIV-HCV) co-infected patients. Here, histopathological features of fatal liver disease in HIV-HCV co-infected patients were comparatively assessed.

METHODS

Liver biopsies of seven HIV-HCV co-infected patients with clinically imminent liver death and advanced immune deficiency were studied. Biopsies of seven asymptomatic patients with stable hepatic and immune functions, who were matched according to their documented duration of HIV-HCV co-infection, served as controls. Inflammatory and fibrotic changes as well as hepatocellular steatosis and cholestasis were assessed semiquantitatively by established scores.

RESULTS

All patients with fatal liver disease had severe immunodeficiency and jaundice, while biliary ducts were patent. Unexpectedly, the extent of hepatic steatosis, inflammatory activity and fibrosis was strikingly similar in both study groups. Importantly, liver failure was observed even in the absence of marked fibrosis. Lobular bilirubinostasis was the only feature that significantly distinguished patients with advanced immunodeficiency and fatal liver disease from the control group.

CONCLUSION

Thus, rapid deterioration of liver function and death can occur in HIV-HCV co-infected patients with advanced immunodeficiency even when liver histology does not reveal markers of end-stage liver disease. Jaundice and marked bilirubinostasis in the absence of biliary tract obstruction seem to herald this complication of chronic hepatitis C in HIV infection.

Outcome after orthotopic liver transplantation in five HIV-infected patients with virus hepatitis-induced cirrhosis

BACKGROUND

We report on our experiences with orthotopic liver transplantation (OLT) in HIV-infected patients. Between July 1998 and October 2001, five HIV-infected patients underwent OLT because of virus-induced liver cirrhosis. One patient suffered from hepatitis B virus (HBV)-, three patients from hepatitis C virus (HCV)- and one patient from HCV/HBV/HDV-related cirrhosis (HDV, hepatitis D virus). The mean duration of HIV infection was 15 years. Patients were prospectively followed up with a mean duration of 25.6 months.

RESULTS

Three patients died 3, 10 and 31 months after OLT, respectively, due to graft failure. The causes of graft failure were: recurrent thrombosis of the hepatic artery, HCV-associated cholestatic hepatitis and chemotherapy-induced liver damage due to Hodgkin's disease, which was diagnosed 17 months after OLT, in addition to chronic HCV disease. The two survivors show a stable liver function and non-progredient HIV infection under antiretroviral therapy 61 and 23 months after OLT, respectively.

CONCLUSIONS

A medium- or even long-term survival after OLT can be achieved in HIV-infected patients without progression of HIV disease under antiretroviral therapy. However, in our study three out of five patients died due to graft failure. Therefore, prognostic criteria have to be defined for the selection of HIV-infected patients, who may benefit from OLT.

Liver transplantation in HIV-infected recipients

Liver transplantation is being evaluated as a therapeutic option for human immunodeficiency virus (HIV)-infected patients with end-stage liver disease, but experience is still scarce. We describe the outcome of 4 HIV-infected patients who underwent liver transplantation in our hospital between July 2002 and April 2003. HIV-infected liver transplant recipients meet the same standard criteria for transplantation as do HIV-negative candidates. In addition, HIV infected persons are required to have a CD4 T-cell count greater than 100/mL (CD4 T-cells are targets for HIV infection). Immunosuppressive regimens, perioperative surgical prophylaxis, and prophylaxis for opportunistic infections are standard in the Liver Transplantation Unit in our hospital. Four patients, including 3 former intravenous drug users, received a liver transplant (2 from deceased donors and 2 from living donors), with a median follow-up of 510 days. Three patients (75%) are alive, with 1 death occurring 17 months posttransplantation in a patient who developed fibrosing cholestatic hepatitis. Rejection occurred in 1 patient, and was managed with no complications. Hepatitis C virus (HCV) recurrence occurred in 3 patients. HIV-infection has remained under control with antiretroviral treatment. A combination of 3 nucleoside analogs was used in 3 patients, with no need for drug adjustments. No opportunistic infections or other significant infectious complications developed. In conclusion, orthotopic liver transplantation seems a safe therapeutic option in the short term for HIV-infected persons with end stage liver disease, including patients with a history of drug abuse. If indicated, an antiretroviral regimen consisting of 3 nucleosides could be used to avoid interactions with immunosuppressive drugs.

Review article: current status of liver transplantation in HIV-infected patients

The increases in survival of patients infected with human immunodeficiency virus is attributed to the introduction of combination human immunodeficiency virus antiviral therapy, better known as highly active anti-retroviral therapy. In fact, survival statistics have improved such that individuals often succumb to other disease entities, notably liver failure and not from acquired immunodeficiency syndrome complications. Liver transplantation has been introduction in this patient population in several centres around the world. This review will discuss the current clinical status of liver transplantation in individuals suffering from human immunodeficiency virus infection.

Liver transplantation in patients with HIV infection

1. Liver transplantation for human immunodeficiency virus (HIV)-positive patients with end-stage liver disease in the era of highly active retroviral therapy has proven to be an effective treatment. The concerns of HIV progression have not been borne out by the growing worldwide experience. 2. CD4 counts are stable and HIV viral load is controllable with medication following liver transplantation. 3. Hepatitis C virus (HCV) coinfection in HIV-positive recipients is universal, but the severity of recurrence does not appear to be different from that in HIV-negative patients with HCV liver disease. 4. Complex pharmacokinetic interactions between the calcineurin inhibitors used for immunosuppression along with protease inhibitors are present, but management directed at recognizing the need for monitoring levels does not appear to increase the risk of toxicity. 5. The degree of immunosuppression from iatrogenic drug therapy and HIV does not lead to increased risk of infectious complications.

HIV and hepatitis C virus co-infection

Since the decline in HIV-related morbidity and mortality after introduction of highly active antiretroviral therapy (HAART) in 1996, liver disease caused by chronic infection with hepatitis C virus (HCV) has become an increasingly important cause of morbidity and mortality among HIV-infected patients infected parenterally with HCV in more developed countries. A third of HIV-infected individuals in Europe and the USA have HCV co-infection. HIV accelerates HCV liver disease especially when HIV-associated immunodeficiency progresses. With the introduction of pegylated interferon in combination with ribavirin, greatly improved treatment options for patients with HIV and HCV co-infection have become available and have led to sustained virological response rates of up to 40%. Furthermore, recent cohort analyses have shown that immune reconstitution induced by HAART can improve the course of hepatitis C leading to a decline in liver-related mortality. However, patients with HCV co-infection are at increased risk of hepatotoxicity from HAART. Owing to the high rates of HIV and HCV co-infection worldwide, new improved treatment strategies and guidelines for the management of co-infection remain a major future goal.

Solid organ transplantation in HIV-infected recipients

HIV is generally regarded as an acceptable reason to exclude a potential recipient from consideration for transplantation. Most of the data in the literature regarding transplantation of HIV sero-positive individuals pertains to the time prior to the administration of Highly Active Anti-Retroviral Therapy (pre-HAART). This data, therefore, provides little guidance for the management of HIV-positive individuals in the current era. The development of HAART has resulted in a decreased mortality. With prolonged survival more HIV-infected individual are developing end stage organ disease from co-existing conditions such as HCV and HBV, and diseases common in the general population such as diabetes mellitus and hypertension. This has lead to clinicians, researchers and patients to actively investigate the role of solid organ transplantation in HIV-infected individuals. In this article We review the literature to date in liver and renal transplantation, including more recent data in patients receiving HAART.

HIV infection and hepatic enzyme abnormalities: intricacies of the pathogenic mechanisms

Liver enzyme elevations are common in human immunodeficiency virus (HIV)-infected patients, and their diagnosis or management may be difficult because of the intricacies of the pathogenic mechanisms involved. These include hepatotoxicity related to the highly active antiretroviral therapy (HAART) regimen, idiosyncratic or immunoallergic mechanisms, and direct cytotoxicity enhanced by an underlying liver disease. Liver enzyme abnormalities may also reflect hepatitis B (HBV) or hepatitis C (HCV) infection, which each have their own risks for chronic immune-mediated liver disease (including hepatitis flare after immune reconstitution) and of direct cytotoxicity. Finally, other factors may affect liver deterioration, including alcohol-related liver disease, nonalcoholic steatohepatitis associated with metabolic syndromes (e.g., hyperlipidemia, diabetes, or being overweight) that are potentially HAART related, and use of medication or illicit drugs (e.g., methamphetamine). A better understanding of these complex interactions, including adjustments of dosages of antiretroviral drugs, will probably help in the management of HIV-infected patients with liver enzyme abnormalities.

Trasplante hepático en pacientes con infección por el VIH: una realidad en el año 2004

According to current estimates, there are 60,000 to 80,000 HIV and HCV coinfected individuals in Spain, and 5,000 to 10,000 HIV and HBV coinfected individuals. Among these patients, 10% to 15% have liver cirrhosis. Thus, end-stage liver disease is one of the major causes of death in our country. Liver transplantation is the only therapeutic option for these patients. Accumulated experience in North America and Europe in the last five years indicates that three-year survival in HIV-positive liver transplant recipients is similar to that of HIV-negative recipients. The selection criteria for HIV transplant candidates includes the following: no history of opportunistic infections, CD4 lymphocyte count higher than 100 cells/mm3, and HIV viral load suppressible with antiretroviral treatment. In Spain, where the majority of patients are former drug abusers, complete abstinence from heroin or cocaine use during two years is also required, with the possibility of the patient being in a methadone program. To date 26 hepatic transplants have been performed in the same number of patients, with only two deaths (7%) after a median follow-up of eight months (1-28). The main problems in the post-transplantation period in all the series has been recurrent HCV infection, which is the principle cause of post-transplantation mortality, and pharmacokinetic and pharmacodynamic interactions between the antiretroviral and immunosuppressive agents. There is little experience with pegylated interferon and ribavirin treatment in this population.

Clinical observation of salvianolic acid B in treatment of liver fibrosis in chronic hepatitis B

AIM

To evaluate the clinical efficacy of salvianolic acid B (SA-B) on liver fibrosis in chronic hepatitis B.

METHODS

Sixty patients with definite diagnosis of liver fibrosis with hepatitis B were included in the trial. Interferon-gamma (IFN-gamma) was used as control drug. The patients took orally SA-B tablets or received muscular injection of IFN-gamma in the double blind randomized test. The complete course lasted 6 months. The histological changes of liver biopsy specimen before and after the treatment were the main evidence in evaluation, in combination with the results of contents of serum HA, LN, IV-C, P-III-P, liver ultrasound imaging, and symptoms and signs.

RESULTS

Reverse rate of fibrotic stage was 36.67 % in SA-B group and 30.0 % in IFN-gamma group. Inflammatory alleviating rate was 40.0 % in SA-B group and 36.67 % in IFN-gamma group. The average content of HA and IV-C was significantly lower than that before treatment. The abnormal rate also decreased remarkably. Overall analysis of 4 serological fibrotic markers showed significant improvement in SA-B group as compared with the IFN-gamma group. Score of liver ultrasound imaging was lower in SA-B group than in IFN-gamma group (HA 36.7 % vs 80 %, IV-C 3.3 % vs 23.2 %). Before the treatment, ALT AST activity and total bilirubin content of patients who had regression of fibrosis after oral administration of SA-B, were significantly lower than those of patients who had aggravation of fibrosis after oral administration of SA-B. IFN-gamma showed certain side effects (fever and transient decrease of leukocytes, occurrence rates were 50 % and 3.23 %), but SA-B showed no side effects.

CONCLUSION

SA-B could effectively reverse liver fibrosis in chronic hepatitis B. SA-B was better than IFN-gamma in reduction of serum HA content, overall decrease of 4 serum fibrotic markers, and decrease of ultrasound imaging score. Liver fibrosis in chronic hepatitis B with slight liver injury was more suitable to SA-B in anti-fibrotic treatment. SA-B showed no obvious side effects.

Fatal reactivation of hepatitis B virus following cytotoxic chemotherapy for acute myelogenous leukemia: fibrosing cholestatic hepatitis

Hepatitis B virus (HBV) is a well known pathogen that sometimes causes fulminant hepatitis in patients undergoing cytotoxic chemotherapy. Fibrosing cholestatic hepatitis (FCH) is a recently recognized unique variant of viral hepatitis, which has been occasionally reported in HBV-infected recipients of liver, renal, or bone marrow transplantation. We present here a 48-yr-old male in whom HBV was reactivated during post-remission chemotherapy for acute myelogenous leukemia, which resulted in rapidly fatal outcome. He manifested with deterioration of liver function in association with enormous replication of HBV. Liver biopsy showed marked ballooning of hepatocytes, cholestasis, and periportal fibrosis with minimum infiltrates. Immunostaining revealed that hepatocytes were strongly positive for hepatitis B surface antigen. Under the diagnosis of FCH, he was treated with lamivudine and interferon beta, which was not effective. Autopsy showed severe atrophy of the liver and marked degeneration of hepatocytes. Hematologists should be aware that FCH is a fatal complication that can develop under post-chemotherapy immunosuppressed conditions. Although there is no convincing evidence, prophylactic administration of lamivudine seems to be a reasonable strategy.