Hepatitis B virus genotype C prevails among chronic carriers of the virus in Korea

Hepatitis B virus (HBV) is one of the major causative agents of chronic liver diseases in Korea. HBV has been classified into 8 genotypes by a divergence of >8% in the entire genomic sequence, and have distinct geographic distributions. There are limited data on the relevance between HBV genotypes and clinical outcomes in Korea. To investigate the clinical feature relating to HBV genotype in Korea, a total 120 serum samples with HBsAg (65 from Seoul and 55 from the other city in Korea) were obtained from each 30 chronic HBV carriers with asymptomatic carrier (ASC), chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). HBV genotype was determined by either enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies against genotype-specific epitopes in the preS2-region or the direct sequencing of small S gene. HBV genotypes were determined in 105 (87.5%) of 120 samples. HBV genotype C was identified in all HBV carriers with ASC, CH, LC, and HCC. Genotypes A, B, D, E, F and G were not detected in any of them. Genotype C HBV prevails predominantly among chronic carriers of the virus in Korea, irrespective of their clinical stages of liver disease and geographic origin.     

Genotype,serotype, and phylogenetic characterization of the complete genome sequence of hepatitis B virus isolates from Malawian chronic carriers of the virus

Hepatitis B virus (HBV) genotypes have distinct geographical distribution. HBV sequences among hepatitis B carriers in Malawi have not been evaluated thus far. HBsAg serotype and genotype of HBV was determined in 20 serum samples from Malawian chronic HBV carriers, and two complete genomes and 13 entire pre-S2/S genes were sequenced directly. Genotype A HBV isolates were found in all of the samples, and serotype with adw2 and ayw2 were detected in three and 17 samples, respectively. In phylogenetic analyses, two complete genomes were classified into a subgroup A' that was described previously in South African isolates of the virus, and were separated from HBV isolates in Western countries with nucleotide differences ranging from 4.1-6.2%. The separation of subgroup A' was also evident in the tree topology of the entire pre-S1/S2, X and precore/core region, but not evident in the small-S region. The nucleotide divergences in subgroup A' were higher than those among genotype A without subgroup A' in the complete genomes as well as each of four open reading frames. All of the 13 pre-S2/S sequences were classified into the subgroup A', and clustered with known HBV isolates with ayw2 in carriers from South Africa and Zimbabwe. Three amino acids in the pre-S2/S gene were characteristic of subgroup A' with ayw2. In conclusion, unique HBV isolates of subgroup A' with ayw2 are prevalent in Malawi, and subgroup A' with a relatively higher nucleotide diversity may be a HBV isolate characteristic of the indigenous population of some African countries.     

Genotype and phylogenetic characterization of hepatitis B virus among multi-ethnic cohort in Hawaii

AIM: Hepatitis B virus (HBV) genomes in carriers from Hawaii have not been evaluated previously. The aim of the present study was to evaluate the distribution of HBV genotypes and their clinical relevance in Hawaii. METHODS: Genotyping of HBV among 61 multi-ethnic carriers in Hawaii was performed by genetic methods. Three complete genomes and 61 core promoter/precore regions of HBV were sequenced directly. RESULTS: HBV genotype distribution among the 61 carriers was 23.0% for genotype A, 14.7% for genotype B and 62.3% for genotype C. Genotypes A, B and C were obtained from the carriers whose ethnicities were Filipino and Caucasian, Southeast Asian, and various Asian and Micronesian, respectively. All cases of genotype B were composed of recombinant strains with genotype C in the precore plus core region named genotype Ba. HBeAg was detected more frequently in genotype C than in genotype B (68.4% vs 33.3%, P<0.05) and basal core promoter (BCP) mutation (T1762/A1764) was more frequently found in genotype C than in genotype B. Twelve of the 38 genotype C strains possessed C at nucleotide (nt) position 1858 (C-1858). However there was no significant difference in clinical characteristics between C-1858 and T-1858 variants. Based on complete genome sequences, phylogenetic analysis revealed one patient of Micronesian ethnicity as having C-1858 clustered with two isolates from Polynesia with T-1858. In addition, two strains from Asian ethnicities were clustered with known isolates in carriers from Southeast Asia. CONCLUSION: Genotypes A, B and C are predominant types among multi-ethnic HBV carriers in Hawaii, and distribution of HBV genotypes is dependent on the ethnic background of the carriers in Hawaii.     

Performance status scale for head and neck scores for oral cancer survivors: predictors and factors for improving quality of life

Objectives

This study aimed to determine the factors associated with long-term quality of life of oral cancer survivors.

Materials and methods

A total of 508 survivors were assessed using the performance status scale for head and neck (PSS-HN), which comprises Eating in Public (E-Public), Normalcy of Diet (N-Diet), and Understandability of Speech (U-Speech). Stepwise multiple linear regression analysis was performed.

Results

The median time between the end of treatment and participating in the survey was 38 months (range, 6–250). Overall, 57–60% of survivors achieved full performance (100 score) of each PSS-HN score, whereas 15% had moderate or severe impairment (≤ 50 score) in E-Public and N-Diet, and 4% had impairment in U-Speech. These three scores deteriorated with increasing T-stage. Age, soft tissue reconstruction, trismus, and missing occlusal contacts on the contralateral side were significantly associated with E-Public and N-Diet. Neck dissection, hard tissue reconstruction, and missing occlusal contacts bilaterally were associated with U-Speech score.

Conclusion

Older age, T4 tumor, and soft tissue reconstruction were predictors of low E-Public and N-Diet performance scores. Increasing mouth opening and maintaining optimal occlusal contacts on the contralateral side may be effective ways to improve N-Diet and E-Public performance. Maintaining optimal occlusal contacts bilaterally may be effective for improving speech performance.

Clinical relevance

Oral health care to increase optimal occlusal contacts and rehabilitation of trismus may be promising factors to improve the functional performance of oral cancer survivors.

     

Epidemiologic and virologic characteristics of hepatitis B virus genotype B having the recombination with genotype C

BACKGROUND & AIMS: Hepatitis B virus (HBV) isolates of genotype B (HBV/B) with or without the recombination with genotype C over the precore region plus core gene have been reported. METHODS: All the 41 HBV/B isolates having the recombination with genotype C (HBV/Ba) possessed the nucleotide 1838 of A in contrast to that of G in all 29 of those without the recombination (HBV/Bj). Taking advantage of this single nucleotide polymorphism, a restriction fragment length polymorphism method was developed that distinguished HBV/Ba from HBV/Bj. RESULTS: HBV/Bj was detected in 90 of the 97 (93%) carriers of HBV/B from Japan, whereas HBV/Ba occurred in all 177 carriers of HBV/B from other countries (China, 20; Hong Kong, 45; Taiwan, 32; Thailand, 30; Vietnam, 30; and the United States, 20 [all of an Asian ethnicity]). In a case-control study, hepatitis B e antigen (HBeAg) and the double mutation in the core promoter (T1762/A1764) were significantly more frequent in 80 carriers each of HBV/Ba than HBV/Bj (35% vs. 18%, P < 0.05 and 33% vs. 15%, P < 0.05, respectively). Differences in the prevalence of HBeAg were more conspicuous between the carriers of HBV/Bj and HBV/Ba older than 30 years (5 of 66 or 8% vs. 16 of 62 or 26%, P < 0.01). CONCLUSIONS: HBV/B having the recombination with genotype C is frequent in Asia, except in Japan, and HBeAg is more prevalent in carriers of HBV/Ba than HBV/Bj.     

Hepatitis B virus infection among residents of a nursing home for the elderly: seroepidemiological study and molecular evolutionary analysis

A seroepidemiological study of HBV infection was carried out to investigate the seroprevalence of hepatitis B surface antigen (HBsAg) and the transmission routes of hepatitis B virus (HBV) infection among residents of a nursing home for the elderly. HBV serum markers were examined in 119 residents and 71 healthcare workers in the institution, as also in 1330 healthy subjects from the same geographical area, as the control group. HBsAg was detected in 6 (5%), 0 and 20 (1.5%) residents, healthcare workers and healthy subjects, respectively. Four residents (A-D) who had HBV-DNA in the serum were studied by molecular evolutionary analysis. The strains derived from residents A, B and D were clustered together within a close range of evolutionary distances. Residents B and D, who were not positive for HBsAg at the time of admission to the institution, subsequently became HBsAg-positive asymptomatic carriers. These results suggested intrainstitutional transmission of HBV in the nursing home for the elderly, and confirmed that the source of transmission of HBV to residents B and D was resident A who was positive for HBsAg. Residents in a nursing home for the elderly should be considered as being a high-risk group for HBV infection, and vaccination against HBV of these groups is recommended.     

Influence of hepatitis B virus genotypes on the development of preS deletions and advanced liver disease

Hepatitis B virus (HBV) mutants with deletions in the preS region have not been evaluated for association with viral genotypes. In a case-control study, HBV DNA samples collected from 80 each of carriers infected with HBV genotype B or C were examined for preS deletions. PreS deletion mutants were found in a total of 37 of 160 (23%) HBV carriers. Carriers with preS deletion mutants were older (56.0 +/- 12.7 vs 49.3 +/- 16.9 years, P < 0.05), were infected more frequently with HBV genotype C (84% vs 40%, P < 0.05), and had more advanced disease, such as liver cirrhosis and hepatocellular carcinoma (54% vs 31%; P < 0.05), than did those without such mutants. In a multivariate analysis, genotype C (odds ratio [OR] = 9.3, P < 0.001) and advanced liver disease (OR = 3.1, P < 0.01) were the most significant variables in association with preS deletions. A direct repeat sequence (TCAGG) was found at the start or at the end of preS1 deletions in 6 of the 20 (30%) cases examined, and preS2 deletions in these cases were clustered over the 5'-terminal half of this region. These results indicate that the development of preS deletion mutants depends on HBV genotypes and that it may be associated with progressive liver disease.     

Reactivation of hepatitis B virus in HBsAg-negative patients with multiple myeloma: two case reports

It was recently reported that hepatitis B virus (HBV) reactivation had occurred in HBsAg-negative lymphoma patients who received rituximab plus steroid combination chemotherapy. HBV reactivation in myeloma patients have not been reported extensively. We describe here two cases of HBV reactivation in HBsAg-negative myeloma patients receiving systemic chemotherapy: one from the medical records of 40 patients and another from 61 patients with prospective HBV-DNA monitoring. In the first case positive for anti-HBs, HBV reactivation was diagnosed when hepatitis developed during conventional chemotherapy such as MP and MCP regimen in a relapsed patient after autologous stem cell transplantation (APBSCT); in the second case positive for anti-HBc and anti-HBs, elevation of HBV-DNA was recognized by serial HBV-DNA monitoring performed prospectively following APBSCT. Interestingly, these two cases had the reduction of the titer of anti-HBs during the treatment, followed by HBV reactivation. These clinical data suggest that the HBV-DNA monitoring is necessary for not only HBsAg-positive but also HBsAg-negative myeloma patients with anti-HBc-positive and/or anti-HBs-positive following transplantation and after conventional chemotherapy in the salvage setting. Establishment of a standard strategy to prevent HBV reactivation is important for myeloma patients receiving systemic chemotherapy.     

Comparison of complete sequences of hepatitis B virus genotype C between inactive carriers and hepatocellular carcinoma patients before and after seroconversion

Background Most patients who acquire chronic hepatitis B virus (HBV) infection by perinatal transmission become inactive carriers (IC) after hepatitis B e (HBe) antigen seroconversion, whereas some patients have persistent abnormal serum transaminase levels and develop hepatocellular carcinoma (HCC) in the anti-HBe-positive phase. The aim of this study was to investigate the HCC-related mutations of HBV. Methods Complete sequences of HBV were examined among eight IC and eight HCC patients infected with HBV genotype C before and after seroconversion. Results The frequency of the T1653 mutation tended to be higher among HCC patients after seroconversion (16.7% vs. 62.5%; P = 0.086). The prevalence of a basal core promoter double mutation (T1762/A1764) was high among both IC and HCC patients after seroconversion (83.3% vs. 87.5%; P = 0.825). Among the HCC patients, a pre-S deletion mutant was detected in 62.5% patients before seroconversion, and in 37.5% patients after seroconversion. The core deletion mutant was also detected in 50% of HCC patients only before seroconversion. Deletion mutants of the pre-S or core region before seroconversion were significantly associated with HCC patients (0% vs. 62.5%; P = 0.007, 0% vs. 50%; P = 0.021, respectively). Conclusions Our data showed a significant association of pre-S and core deletion mutants before seroconversion with HCC development. The T1653 mutation after seroconversion was frequently found in HCC patients infected with HBV genotype C. These results suggest that mutations may be predictive factor for development of HCC.     

Liver transplantation-associated de novo hepatitis B virus infection: application of molecular evolutionary analysis

OBJECTIVE: De novo hepatitis B virus (HBV) infection after liver transplantation has recently been reported to be associated with donors without serum hepatitis B surface antigen (HbsAg) but with hepatitis B core antigen (anti-HBc). We elucidate the source of de novo HBV infection after liver transplantation by molecular evolutionary analysis. METHODS: The serum sample was obtained from a recipient who underwent living related liver transplantation. He was negative for all HBV-related serum markers before the transplantation. The recipient became seropositive for HBsAg at 6 months after transplantation. The liver tissue was obtained from a donor who was seronegative for HBsAg, but positive for anti-HBs and anti-HBc. RESULTS: HBV DNA was detected from the serum and liver tissue in a recipient and donor, respectively. A total of 5 clones each of small-S gene of HBV from the donor and recipient were sequenced. A phylogenetic tree analysis based on small-S gene revealed that all isolates derived from the recipient and donor were clustered together within a close range of evolutionary distances. These results indicated that HBV was transmitted by the liver graft from the donor. CONCLUSIONS: Molecular evolutionary analysis can be adopted for the study of the transmission route of viral infection via organ transplantation.