Miho Ogawa

Clinical features and viral sequences of various genotypes of hepatitis B virus compared among patients with acute hepatitis B

Clinical manifestations and viral sequences of core promoter and precore/core region were compared among various genotypes of hepatitis B virus (HBV) in 25 patients with acute hepatitis. The genotype in patients with acute hepatitis was distributed differently from that among chronic hepatitis patients in Japan, which are predominantly genotypes B and C. Of 25 patients with acute hepatitis, 14 had genotype A, five genotype B and six genotype C. Serum total bilirubin levels were significantly higher in patients with genotype A than in those with genotype C. Prothrombin time was shorter in patients with genotype B than those with genotype A or C. Total bilirubin was lower in patients with short duration of acute hepatitis. The serum ALT value remained above 1000 IU/l for over 10 days in 79% of patients with genotype A. This prolonged duration of hepatitis in patients with genotype A may contribute to hyperbilirubinemia. Sequence analysis revealed no difference in the number of mutations in precore/core regions among the three genotypes. Although the double mutation, A-T and G-A at 1762 and 1764, respectively, was found in two patients each with genotype A and C, these mutations were not related to the hepatitis B e antibody (HbeAg)/hepatitis B e antibody (HbeAb) phenotype. Two of seven patients with thymidine at 1858 also had a G to A mutation at 1896. Thus, the difference in the genotype little influenced the HBeAg/HBeAb phenotype in acute hepatitis patients. Understanding the viral genotypes in acute HBV infection may be valuable in predicting the clinical course of acute hepatitis B (AHB).

Prevalence of herpesviridae and hepatitis virus sequences in the livers of patients with fulminant hepatitis of unknown etiology in Japan.

Background:Background: Fulminant non-A, non-B, non-C hepatitis has a high mortality rate, making the identification of its causative agent imperative. Cytomegalovirus, Epstein-Barr virus, human herpesvirus-6, and herpes simplex virus are all members of the herpesviridae family that are associated with fatal hepatic failure. We investigated the involvement of herpesviridae and hepatitis virus in the pathogenesis of fulminant hepatitis. Methods: The study participants consisted of 11 patients with fulminant hepatitis and 11 with acute hepatitis negative for known hepatitis viral markers and any other liver diseases. Viral DNA was extracted from liver tissues and amplified. In situ hybridization was then performed for 1 patient to detect viral DNA and RNA, and viral protein was localized by monoclonal antibodies. Results: Human herpesvirus-6 was detected in liver tissues from seven patients, (five children and two adults) with fulminant hepatitis and two patients with acute hepatitis. Two patients with fulminant hepatitis also had cytomegalovirus in the liver. Although Epstein-Barr virus and herpes simplex virus were detected in the patients with fulminant hepatitis, they were not specific to these patients. In situ hybridization in one of the patients localized DNA and RNA of human herpesviru-6 in hepatocyte nuclei, and an envelope antigen of this virus was detected in hepatocyte cytoplasm. Conclusions: Human herpesvirus-6 was frequently detected in Japanese pediatric patients with fulminant non-A, non-B, non-C hepatitis. Although the significance of human herpesvirus-6 in liver pathogenesis remains unclear, this virus may replicate in hepatocytes in some patients with acute onset hepatitis.

Effectiveness and long-term outcome of lamivudine therapy for acute hepatitis B

We describe lamivudine therapy for acute hepatitis B (AHB) with prolonged high alanine aminotransferase (ALT) and HBV DNA. Three male patients (27-31 years old) had prolonged high ALT, bilirubinemia, and prolonged prothrombin time for over 10 days. Lamivudine was administered at a dose of 150 mg per day because of the threat of acute liver failure. All three patients tolerated the drug well. Serum HBV DNA levels quickly became undetectable, and both the ALT level and liver function tests normalized within 1 month in all three patients. HBeAg and HBsAg disappeared during the clinical course of AHB, and HBsAb was not detected in two of the three patients during the 1-year follow-up. Direct sequence analysis revealed no significant substitution of amino acids in the precore and core regions, including the HLA class II epitope. Lamivudine might prevent the progression of severe AHB to fulminant liver failure, and it appears to modify the clinical course of the disease.

Molecular analysis of antigenicity and immunogenicity of a vaccine-induced escape mutant of hepatitis B virus

Background: To analyze the mechanisms of mutant escape, we established a murine model of hepatitis B virus (HBV) infection and studied the interaction of the envelope protein of the virion with various kinds of anti-hepatitis B antibody. Methods: Mutation from glycine to arginine at aa145 was introduced into replication-competent DNA of HBV. The resulting mutant HBV DNA was transfected into cultured hepatoma cells and livers of mice using liposome-mediated gene transfer. Then, interactions between the antigenic envelope protein (in culture or in circulation) and anti-hepatitis B antibody were examined. Results: Mutant envelope protein escaped human hepatitis B immunoglobulin, rabbit polyclonal anti-hepatitis B surface antigen (HBsAg) antibody, and monoclonal anti-a antibody in vitro and in vivo. There was a difference in the degree of inhibition between hepatitis B immunoglobulin and the other two antibody types in vitro. Transfection with an HBV construct containing a mutation in the a-loop resulted in levels of HBsAg in circulation and seroconversion to anti-HBs antibody that were similar to those produced by a wild-type construct. Conclusions: The degree of escape by the mutant envelope protein differed according to antibody type. Of the three types of antibody used in this study, HBV immunoglobulin was least affected by mutation in the a-loop. There appears to be no correlation between antigenicity and immunogenicity of the escape mutant, and the a-loop mutant may cause hepatitis with the usual serum viral markers.

Genotypic analysis of hepatitis B virus from patients with fulminant hepatitis: comparison with acute self-limited hepatitis

AIM/BACKGROUND: There is an increasing evidence that certain hepatitis B virus (HBV) strains may contribute to the pathogenesis of fulminant hepatitis B (FHB). Recently, we reported that genotypes of HBV influence the clinical course of acute self-limited hepatitis B (AHB). In this study, we compared clinical features of FHB between different HBV genotypes and compared the prevalence of each genotype between FHB and AHB patients. METHODS: The subjects consisted of seven patients with FHB and 25 patients with AHB. The core promoter and precore region were directly sequenced following polymerase chain reaction, and genotype was determined by restriction fragment length polymorphism analysis of the S gene. RESULTS: Of the seven FHB patients, one had genotype A, one had genotype B, four had genotype C, and one had genotype D. Six of the seven FHB patients were infected by heterosexual contact; one FHB patient who was not infected by heterosexual contact had genotype C. All four FHB patients with genotype C had a short duration clinical course. In one patient with genotype A, the time from onset of hepatitis to hepatic coma was 30 days. These results are similar to those of the patients with AHB, in which clinical course was longer in patients with genotype A than in patients with genotype C. CONCLUSION: Viral genotype can be used to predict the clinical course of both FHB and AHB.

Small-bowel hemorrhage caused by cytomegalovirus vasculitis following fulminant hepatitis.

We describe life-threatening vasculitis of the small bowel following fulminant hepatitis. A 35-year-old man was admitted to our hospital due to consciousness disturbance and jaundice. He was diagnosed with fulminant hepatitis, and recovered after intensive medical care that included corticosteroid administration and artificial liver support. During reduction of the dosage of steroid, massive gastrointestinal hemorrhage occurred from the upper jejunum, revealed by arteriography. The hemorrhage could not be stopped, so a portion of the ileum, including the bleeding point, was excised. However, the intestinal hemorrhage continued from several small ulcers remaining outside the resected area. Pathological findings revealed an ulcerative region that was diagnosed as cytomegalovirus (CMV) vasculitis. His serum level of CMV (measured by real-time-detection polymerase chain reaction [PCR]) was high. Ganciclovir therapy was started, and manifestations of the CMV infection improved. In addition to CMV, PCR assay for hepatitis A virus (HAV), HBV, HCV, Epstein-Barr virus (EBV), human herpes virus-6 (HHV-6), and herpes simplex virus (HSV) was performed, but no viruses other than CMV were detected. We are the first to report such a case. We conclude that the possibility of CMV enteritis should be considered when patients present with unexplained fever and gastrointestinal hemorrhage following fulminant hepatitis, and we conclude that the early administration of ganciclovir should be considered.

Lamivudine treatment for acute exacerbation of hepatitis B in patients undergoing immunosuppressive therapy

Lamivudine was administrated to six patients with acute exacerbation of hepatitis B who were undergoing immunosuppressive therapy. All patients had chronic hepatitis B and were receiving immunosuppressive therapy for other primary diseases (hematologic malignancies, collagen diseases, renal transplantation) when the hepatitis flared up. Only one patient tested positive for the hepatitis B virus e (HBe) antigen. All patients had normal ALT levels and were anti-HBe-positive before immunosuppressive therapy. The patients were treated with 150 mg of lamivudine daily. Lamivudine was well tolerated and showed no effect on the primary disease. In all patients, hepatitis B virus (HBV) DNA levels decreased in response to lamivudine administration. Four patients recovered from exacerbation, but two patients died from complications. Molecular analysis revealed that, regardless of whether patients had the wild HBV genotype or mutations within the core promoter or precore HBV regions, the effectiveness of lamivudine therapy was the same. These results demonstrated that lamivudine is very effective for treating acute exacerbation of chronic hepatitis B that occurs while a patient is undergoing immunosuppressive therapy, regardless of the phenotype of the virus.

Living-related partial liver transplantation for decompensated hepatitis B without reactivation of hepatitis B in the following 30 months.

We report a case of living-related partial liver transplantation for decompensated hepatitis B without reactivation of hepatitis B in the following 30 months, and we analyze the factors that indicate a favorable prognosis for transplantation. The 42-year-old female patient received continuously administered lamivudine before transplantation, and hepatitis B virus immunoglobulin (HBIG) from the anhepatic phase to the present. Currently, she shows a normal aminotransferase level and is negative for hepatitis B surface antigen and hepatitis B virus (HBV) DNA by polymerase chain reaction amplification. Sequence analysis was performed. The entire precore/core region and part of the polymerase region of HBV were sequenced by a direct sequencing method after polymerase chain reaction. No specific mutation was found in these regions. These observations show that the key factors in the long-term successful treatment of this patient appear to be the combination therapy of lamivudine and HBIG that the patient received from around the time of the transplantation. Furthermore, the lack of specific mutations, including lamivudine resistant-mutations, is likely to represent an additional factor in the effectiveness of this treatment.

Different antibody responses against hepatitis B surface antigen among mouse strains transfected with mutant viral DNA

Background: Rapid seroconversion from hepatitis B surface antigen (HBsAg) to anti-HBs antibody is seen in most patients with fulminant hepatitis B. It is unclear whether viral mutation or host immune background is responsible for such enhanced host reaction to hepatitis B virus (HBV). To investigate interaction between virus mutation and host immune background, we established a mouse model of hepatitis B using liposome-mediated gene transfer. Methods: A mixture of liposomes and full-length viral DNA derived from hepatitis B patients was injected into three strains of purebred mice intrahepatically. After injection, HBsAg and antibody in liver and serum were serially measured. Results: Three days after transfection, viral transcript and antigen were detected in the liver and serum. Ten days after transfection with wild-type DNA, hepatitis B surface antibody was detectable in two of the three strains. Mice that did not produce antibody after transfection with wild-type DNA produced a high amount of serum antibody against surface antigen when transfected with fulminant hepatitis-associated DNA. Conclusions: The present results are consistent with previous clinical observations of rapid HBsAg seroconversion in patients with fulminant hepatitis B. Further studies are needed to determine which mutations are responsible for differences in immunogenicity between HBV strains.