{'fraction_non_alphanumeric': 0.027577639751552797, 'fraction_numerical': 0.01565217391304348, 'mean_word_length': 5.072398190045249, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Hepatitis B immunization after liver transplantation: What is the answer?

Hepatitis B is a serious infectious disease causing substantial morbidity and mortality worldwide. It is estimated that more than two billion people have evidence of previous hepatitis B infection, resulting in more than 350 million individuals with chronic hepatitis B virus (HBV) infection. In turn, this leads to an estimated one million deaths each year due to chronic end-stage liver disease and hepatocellular carcinoma. Liver transplantation is effective therapy for fulminant hepatitis B or chronic hepatitis B with decompensation and/or hepatocellular carcinoma. From 1987-2002, 3,403 liver transplants were performed in the United States for adults with liver disease due to hepatitis B.1 Patients undergoing transplantation for hepatitis B have a high risk of recurrence without effective adjuvant therapy. Many centers use both hepatitis B immune globulin (HBIG) and antiviral agents to prevent recurrence. HBIG is expensive, and stimulation of the patient’s own immune system with hepatitis B vaccine has been attempted to eliminate the need for additional therapy after liver transplantation. Multiple trials of hepatitis B vaccination after transplantation for hepatitis B have recently been reported.2-6 Interpretation and comparison of the numerous studies available is complicated by different methodologies and end points. Anti-HBs levels ranging from 10 IU/L to 500 IU/L have been used to define response in the posttransplant setting. In addition, these studies have differed with regard to vaccine antigens, vaccination schedules and routes of administration, and approaches to the use of antivirals and HBIG. Overall, an anti-HBs level 500 IU/L, without the use of hepatitis B immune globulin, was achieved in 5.9-80% of treated patients in these studies, emphasizing the certainty that other variables are involved. The highest response rates were reported by Bienzle et al., who studied 20 patients who were HBeAg and HBV DNA negative prior to transplantation, were on stable doses of HBIG, and received hepatitis B vaccine combined with the novel adjuvant system composed of 3-deacylated monophosphoryl lipid A and Quillaja saponaria Molina, a purified natural saponin molecule in an oil/water emulsion.2 Patients received from 2-8 vaccinations. Four patients also received antiviral therapy, three with lamivudine and one with famciclovir. Eighty percent of patients achieved anti-HBs levels 500 IU/L and were free of HBIG use after being followed for 10-27 months. In this issue, Starkel et al. present the results of a small, nonrandomized clinical study of a new hepatitis B vaccine adjuvanted by monophosphoryl lipid A. Fifteen adult patients stable for at least three years after liver transplantation were studied. Ten subjects were transplanted for HBV-related disease (mean age 49 years), and 5 subjects were transplanted for liver disease of nonviral etiology (mean age 65 years). Two of the hepatitis B patients were transplanted for fulminant hepatic failure. Of the 8 chronic HBV subjects in the study, all were negative for HBV DNA by bDNA assay prior to transplantation. Six of 8 were infected with an HBV precore mutant prior to liver transplantation, and two subjects had been infected with wild-type HBV. It is not clear if any of the patients had received antiviral therapy prior to or after transplantation. All subjects were receiving low-level immunosuppression (tacrolimus or cyclosporine) and HBIG prophylaxis (5,000 IU every 6 weeks intravenously). No subjects had concomitant viral infection (human immunodeficiency virus [HIV], hepatitis C virus [HCV], hepatitis D virus [HDV]), and all were seronegative for HBsAg and HBV-DNA at study entry. The vaccine used in this study was recombinant purified HBsAg (20 mcg/0.5 mL) formulated with sucrose and adjuvanted with MPL. The vaccine was administered as double doses (i.e., two 20 mcg doses) intramuscularly in the deltoid on a schedule of 0, 4, and