Kenichiro Kashiwagi

Human T Lymphotropic Virus Type 1 Infection Influences Hepatitis C Virus Clearance

To explore the effect of human T lymphotropic virus type 1 (HTLV-1) infection on hepatitis C virus (HCV) infection, a survey for these viral infections was conducted that involved 2280 residents in an area in which HTLV-1 and HCV are endemic. The response of patients with HCV and HTLV-1 to interferon (IFN)-alpha treatment was also assessed. Antibody to HCV was detected in 13.8% of the residents tested, and antibody to HTLV-1 was detected in 15.4%. The prevalence of HCV RNA was significantly higher among residents who had antibodies to both HCV and HTLV-1 than in those who had antibodies to HCV only (P<.05). Sustained elimination of HCV RNA by IFN was significantly more frequent among patients with HCV alone than among those with HCV and HTLV-1. By logistic regression analysis, HTLV-1 infection was associated with nonresponse to IFN treatment. Thus, HTLV-1 infection affects the clearance, both natural and in association with IFN treatment, of HCV.

Double point mutation in the core promoter region of hepatitis B virus (HBV) genotype C may be related to liver deterioration in patients with chronic HBV infection.

Background and Aim:  Hepatitis B virus (HBV) genotype C has a more severe pathogenesis than genotype B in Japan. We retrospectively investigated the relationship between HBV genotype and the core promoter (CP) (nt 1762 and 1764) and precore (PreC) (nt 1896) mutations of the HBV genome.

Hepatitis C virus (HCV) RNA level determined by second-generation branched-DNA probe assay as predictor of response to interferon treatment in patients with chronic HCV viremia

Using first- and second-generation branched-DNA probe assays (1st- and 2nd-bDNA), we investigated the predictors of favorable clinical response to interferon (IFN) treatment in patients with chronic HCV viremia. A total of 122 patients (85 genotype 1b and 37 genotype 2a) with chronic HCV viremia received 24-week IFN-α treatment. Patients with sustained clearance of serum HCV RNA by polymerase chain reaction at six months after IFN treatment were defined as having a sustained response (SR). HCV RNA level was determined by 1st- and 2nd-bDNA assays prior to treatment. Mean HCV RNA level by 1st-bDNA was significantly higher in genotype 1b patients [5.4 × 106 HCV genome equivalent (Meq)/ml] than in genotype 2a patients (0.9 Meq/ml) (P < 0.05). There was no significant difference between patients with these genotypes in the level by 2nd-bDNA (1b: 5.2 Meq/ml and 2a: 3.1 Meq/ml). SR was achieved by 43 (35.2%) of 122 patients. Mean HCV RNA levels by both the 1st- and 2nd-bDNA of SR patients (1.0 and 1.9 Meq/ml) were significantly lower than those of non-SR patients (5.3 and 6.0 Meq/ml) (both P < 0.05). The SR rate in genotype 2a patients (59.5%) was significant higher than in genotype 1b patients (24.7%) (P < 0.05). Stepwise logistic regression analysis showed that HCV RNA level ≦1.0 Meq/ml by 2nd-bDNA (odds ratio = 7.6, compared to level > 1.0 Meq/ml, P < 0.05) was a significant predictive cutoff for SR. Using 2nd-bDNA, a significantly higher rate of SR was found in genotype 1b patients with level ≤1.0 Meq/ml (57.6%) than in those with level >1.0 Meq/ml (3.8%) (P < 0.05). The SR rate of genotype 2a patients with level >1.0 Meq/ml (68.6%) was somewhat higher than for those with level ≤1.0 Meq/ml (52.4%). These findings suggested that, using 2nd-bDNA, a low HCV RNA level of ≦1.0 Meq/ml was the most favorable marker of successful IFN treatment and that patients with genotype 2a, even those with level >1.0 Meq/ml, had a high rate of SR to IFN treatment.