Kunihiko Hino

Transmission of Hepatitis C Virus from Mothers to Infants

Background Although there are case reports of vertical transmission of hepatitis C virus (HCV), it remains uncertain to what extent infected mothers transmit this virus to their infants. Methods We investigated the transmission of HCV from infected mothers to their babies by analyzing HCV RNA in the blood. Three independent studies were performed. First, 7698 parturient women were tested for anti-HCV antibodies; 53 were positive. Their 54 infants (including one set of twins) were followed prospectively for at least six months and tested for HCV infection. Second, the babies of six women with known HCV disease were prospectively studied. Third, the families of three HCV-infected infants were examined retrospectively. Results Of the 53 antibody-positive mothers, 31 were also positive for serum HCV RNA. Three of the 54 babies born to these mothers (5.6 percent) became positive for HCV RNA during the follow-up period. None of the babies of the 22 women who were antibody-positive but HCV RNA-negative became po...

Hepatitis B virus genomic sequence in the circulation of hepatocellular carcinoma patients: comparative analysis of 40 full-length isolates.

SummaryWe determined full-length nucleotide sequence of hepatitis B virus (HBV) genome in sera from 40 Japanese patients with HBsAg-positive hepatocellular carcinoma (HCC), in order to obtain information on HCC-specific characteristics, if any, of the HBV genome. Direct sequencing of the long distance PCR products starting from 50 μl of serum samples revealed that 95% of our isolates were of genotype C, and that mutations and deletions/insertions were very common. With respect to envelope protein genes, deletions and missense mutations were frequent in preS2, and the determinant a domain of HBsAg was rich in “antibody-escape” mutations. Within the precore/core region, the most remarkable mutation was the replacement of proline of wild type by other amino acids at codon 130 of the core gene, which was found in 58% of our isolates, while precore-stop mutation was found in 45%. Most interestingly, however, about 90% of our isolates had mutations at nt positions 1762 (A-to-T) and 1764 (G-to-A) within the core promoter, which had been implicated in “e-suppressive” phenotype of HBV genome. G-to-A at nt 1613 and C-to-T at nt 1653 within enhancer II and T-to-C/A at nt 1753 within core promoter were also evident: 38%, 53%, and 40%, respectively. It was interesting that some of the characteristics observed in our isolates form HCC patients had been previously implicated in fulminant hepatitis and/or acute exacerbation of chronic hepatitis.

Treatment of chronic hepatitis C with high-dose interferon α-2b

A comparative study of three different high-dose regimens of interferon-α-2b (IFN) was conducted in patients with chronic hepatitis C to determine which was better at obtaining a sustained remission. A total of 126 patients were assigned randomly to one of three groups: group A was given 10 million international units (MIU) of IFN six times a week for eight weeks; group B was given 10 MIU IFN six times a week for four weeks followed by three times a week for an additional eight weeks; group C was given 10 MIU IFN six times a week for two weeks followed by three times a week for 12 weeks. The total dose administered to each group was 480 MIU/patient. Only the dosing schedule varied among the three groups. Among 98 efficacy-evaluable patients, a sustained alanine aminotransferase (ALT) response, defined as persistent normalization of the ALT for greater than six months after the termination of treatment, was achieved in 21.2% (7/33) of group A, 42.3% (11/26) of group B, and 54.5% (18/33) of group C patients. Similarly, a sustained loss of measurable serum hepatitis C virus RNA was observed in 28.6% (8/28) of group A, 40.9% (9/22) of group B, and 48.3% (14/29) of group C patients. Based upon these data, it can be concluded that 10 MIU of IFN administered six days a week for two weeks followed by three times a week for an additional 12 weeks produces the highest rate of both biochemical and virological responses to IFN therapy in patients with chronic HCV.

High Prevalence of Antibodies to Hepatitis A and E Viruses and Viremia of Hepatitis B, C, and D Viruses among Apparently Healthy Populations in Mongolia

ABSTRACT The prevalence of infection with hepatitis A virus (HAV), HBV, HCV, HDV, and HEV was evaluated in 249 apparently healthy individuals, including 122 inhabitants in Ulaanbaatar, the capital city of Mongolia, and 127 age- and sex-matched members of nomadic tribes who lived around the capital city. Overall, hepatitis B surface antigen (HBsAg) was detected in 24 subjects (10%), of whom 22 (92%) had detectable HBV DNA. Surprisingly, HDV RNA was detectable in 20 (83%) of the 24 HBsAg-positive subjects. HCV-associated antibodies were detected in 41 (16%) and HCV RNA was detected in 36 (14%) subjects, none of whom was coinfected with HBV, indicating that HBV/HCV carriers account for one-fourth of this population. Antibodies to HAV and HEV were detected in 249 (100%) and 28 (11%) subjects, respectively. Of 22 HBV DNA-positive subjects, genotype D was detected in 21 subjects and genotype F was detected in 1 subject. All 20 HDV isolates recovered from HDV RNA-positive subjects segregated into genotype I, but these differed by 2.1 to 11.4% from each other in the 522- to 526-nucleotide sequence. Of 36 HCV RNA-positive samples, 35 (97%) were genotype 1b and 1 was genotype 2a. Reflecting an extremely high prevalence of hepatitis virus infections, there were no appreciable differences in the prevalence of hepatitis virus markers between the two studied populations with distinct living place and lifestyle. A nationwide epidemiological survey of hepatitis viruses should be conducted in an effort to prevent de novo infection with hepatitis viruses in Mongolia.

Frequent presence of HBV in the sera of HBsAg‐negative, anti‐HBc‐positive blood donors

BACKGROUND: Recent studies have revealed that HBV may not be cleared even after the disappearance of serum HBsAg. The purpose of this study was to investigate whether the replication of HBV persists in HBsAg‐negative blood donors who lack apparent liver disease.

Clinical implications of mutations C-to-T1653 and T-to-C/A/G1753 of hepatitis B virus genotype C genome in chronic liver disease.

SummaryAmong many mutational “hot spots” on hepatitis B virus (HBV) genome, A-to-T1762 and G-to-A1764 within the core promoter have been underscored in view of disease association as well as viral expression/replication. Although to a lesser extent, C-to-T1653 and T-to-V(C/A/G)1753 were also noteworthy in our previous study. To assess the clinical significance of these mutations, we determined the nucleotide sequence of an HBV DNA fragment covering these sites in HBsAg-positive blood donors (n=160) and patients with chronic hepatitis (n=66), liver cirrhosis (n=45), and hepatocellular carcinoma (n=58), most of whom were infected with genotype C HBV (subtype adr). In cases where HBe antigen was positive, the frequency of T1653 and/or V1753 showed a striking increment from chronic hepatitis patients (18%) to liver cirrhosis and/or hep- atoma patients (82%), whereas that of T1762/A1764 was already high in chronic hepatitis patients (76%). In HBe antigen-negative cases, by contrast, significant difference in the frequency of T1653/V1753 mutants was found between blood donors (22%) and chronic hepatitis patients (67%). Our results suggest that T1653/V(particularly C)1753 mutants are more closely associated than T1762/A1764 with the progression of liver disease from chronic hepatitis to cirrhosis in HBe antigen-positive patients. A system of site-directed mutagenesis PCR RFLP was constructed to diagnose T1653 and C/A1753 more conveniently. Detecting T1653 and C/A1753 by this method would contribute to the differential diagnosis of HBV-associated liver disease.

Precore and core promoter mutations, hepatitis B virus DNA levels and progressive liver injury in chronic hepatitis B

BACKGROUND/AIMS To elucidate the viral factors responsible for progressive liver injury in chronic hepatitis B. METHODS We analyzed 179 persistently infected patients (21 asymptomatic carriers, 126 with chronic hepatitis and 32 with cirrhosis) with genotype C hepatitis B virus (HBV). HBeAg/anti-HBe, levels of HBV DNA, mutations in the basic core promoter (BCP) region at nucleotides 1762/1764 and mutation in the precore (preC) region at nucleotide 1896 were determined. Serial samples from 18 patients also were analyzed. RESULTS HBeAg/anti-HBe and HBV DNA levels per se were not related to liver fibrosis. The frequency of BCP mutations increased with progression of liver fibrosis. Although the preC mutation was detected more often among the LC group, the role of this mutation in progression of fibrosis seems less than that of the BCP mutations. Sequential analysis showed that (1) rapidly progressing cases were positive continuously for double mutations in the BCP with a wild-type precore sequence, and (2) asymptomatic cases with anti-HBe acquired the preC mutation during their clinical course. CONCLUSIONS Double mutations in the BCP region at nucleotide 1762/1764 are closely related to progression of chronic liver disease. Acquisition of mutation in the preC region at nucleotide 1896 may contribute to inactivation of chronic liver disease.

Epidemiology of genotypes of hepatitis C virus in Japanese patients with type C chronic liver diseases: A multi-institution analysis

Sixteen medical institutions in Japan collaborated in this study of the epidemiology of hepatitis C virus (HCV) genotypes. A total of 4176 patients with type C chronic liver disease, from the four main islands of Japan, were evaluated. Of those evaluated, 2794 had chronic hepatitis, 727 had liver cirrhosis and 655 had hepatocellular carcinoma. The HCV genotype of the patients was determined by an enzyme‐linked immunosorbent assay based on serological genotype 1‐ and 2‐specific recombinant peptides (SG‐1 and SG‐2, respectively) of the NS4 region. The prevalence of SG‐1 and SG‐2 HCV was similar in the four main islands of Japan. SG‐1 HCV predominated in each disease category (69–76%). The percentage of patients with SG‐1 HCV increased by 7%, while that of patients with SG‐2 HCV decreased by 7%, as liver disease progressed in severity from chronic hepatitis to carcinoma (P < 0.001). Patients with either SG‐1 or SG‐2 had a similar mean age and history of blood transfusion. In conclusion, SG‐1 HCV was found to predominate in Japan, and the HCV genotype was found to be related to the stage of hepatitis C disease.

Clinical course of acute hepatitis C and changes in HCV markers

Chronological measurements of various HCV markers were conducted to clarify the course and prognosis of acute hepatitis C. Among 49 patients with acute non-A, non-B hepatitis, 32 (65.3%) were diagnosed as having acute hepatitis C by these markers. Twenty-four (82.8%) of 29 patients with posttransfusion hepatitis were type C, while only eight (40.0%) of 20 patients with sporadic hepatitis were type C. Patients were also divided into those who returned to normal within one year based on changes in s-ALT levels and unresolved cases. Anti-HCV was present in 11 (44.4%) of 25 resolved cases and in 21 (87.1%) of 24 unresolved cases. Only one case was continuously positive for HCV-RNA although s-ALT levels returned to normal. In addition, quantitative determinations were conducted on those positive for anti-HCVs. Anti-second generation tested positive in all HCV-RNA-positive cases and positive rates were highest from the onset of hepatitis. In unresolved patients with continuous HCV infection, anti-core increased and titers at 12 months were 10 units or more in all cases. On the other hand, in eight of 10 resolved cases, titers declined gradually after initial seroconversion and titers were 10 units or less at 12 months. From these results, second generation anti-HCV was considered most useful in early diagnosis of acute hepatitis C and anti-core titer was considered most useful in predicting prognosis of acute hepatitis C.

Current State of Interferon Therapy for Chronic Hepatitis C

The current status of interferon (IFN) therapy in chronic hepatitis C is presented, focusing on the results of studies in Japan. Depending on the IFN treatment regimen used in chronic hepatitis C, it is possible to eradicate HCV in a relatively high percentage of patients (about 40%) and to achieve a cure for chronic hepatitis C. The objective of treatment should therefore be the eradication of HCV. The efficacy of IFN in chronic hepatitis C is dependent on the dosage of IFN, duration of treatment, liver histology findings, serum HCV-RNA levels, and HCV genotype. Besides a flu-like syndrome, many adverse reactions are associated with high-dose, long-term IFN treatment. However, as a rule, full recovery or improvement follows prompt withdrawal of IFN. By modification of the IFN, it will be possible to reduce adverse reactions and to create a more effective IFN to further enhance the effect of IFN in chronic hepatitis C.