Kazunori Kusumoto

Increased rate of death related to presence of viremia among hepatitis C virus antibody–positive subjects in a community-based cohort study†

The overall mortality of patients infected with hepatitis C virus (HCV) has not been fully elucidated. This study analyzed mortality in subjects positive for antibody to HCV (anti‐HCV) in a community‐based, prospective cohort study conducted in an HCV hyperendemic area of Japan. During a 10‐year period beginning in 1995, 1125 anti–HCV‐seropositive residents of Town C were enrolled into the study and were followed for mortality through 2005. Cause of death was assessed by death certificates. Subjects with detectable HCV core antigen (HCVcAg) or HCV RNA were considered as having hepatitis C viremia and were classified as HCV carriers; subjects who were negative for both HCVcAg and HCV RNA (i.e., viremia‐negative) were considered as having had a prior HCV infection and were classified as HCV noncarriers. Among the anti–HCV‐positive subjects included in the analysis, 758 (67.4%) were HCV carriers, and 367 were noncarriers. A total of 231 deaths occurred in these subjects over a mean follow‐up of 8.2 years: 176 deaths in the HCV carrier group and 55 in the noncarrier group. The overall mortality rate was higher in HCV carriers than in noncarriers, adjusted for age and sex (hazard ratio, 1.53; 95% confidence interval, 1.13‐2.07). Although liver‐related deaths occurred more frequently among the HCV carriers (hazard ratio, 5.94; 95% confidence interval, 2.58‐13.7), the rates of other causes of death did not differ between HCV carriers and noncarriers. Among HCV carriers, a higher level of HCVcAg (≥100 pg/mL) and persistently elevated alanine aminotransferase levels were important predictors of liver‐related mortality. Conclusion: The presence of viremia increases the rate of mortality, primarily due to liver‐related death, among anti–HCV‐seropositive persons in Japan. (HEPATOLOGY 2009.)

Early diagnostic potential for hepatocellular carcinoma using the SELDI ProteinChip system.

Early detection of HCC increases the potential for curative treatment and improves survival. To facilitate early detection of HCC, this study sought to identify novel diagnostic markers of HCC using surface‐enhanced laser desorption ionization time‐of‐flight mass spectrometry (SELDI‐TOF/MS) ProteinChip technology. Serum samples were obtained from 153 patients with or without HCC, all of whom had been diagnosed with HCV‐associated chronic liver disease. To identify proteins associated with HCC, serum samples were analyzed using SELDI‐TOF/MS. We constructed an initial decision tree for the correct diagnosis of HCC using serum samples from patients with (n = 35) and without (n = 44) HCC. Six protein peaks were selected to construct a decision tree using this first group. The efficacy of the decision tree was then assessed using a second group of patients with (n = 29) and without (n = 33) HCC. The sensitivity and specificity of this decision tree for the diagnosis of HCC were 83% and 76%, respectively. For a third group, we analyzed sera from seven patients with HCC obtained before the diagnosis of HCC by ultrasonography (US) and from five patients free of HCC for the past 3 years. Use of these diagnostic markers predicted the diagnosis of HCC in six of these seven patients before HCC was clinically apparent without any false positives. Conclusion: Serum profiling using the SELDI ProteinChip system is useful for the early detection and prediction of HCC in patients with chronic HCV infection. (HEPATOLOGY 2007;45:948–956.)

Alanine aminotransferase level as a predictor of hepatitis C virus-associated hepatocellular carcinoma incidence in a community-based population in Japan

We evaluated the utility of alanine aminotransferase (ALT) measurements in predicting the incidence of hepatocellular carcinoma (HCC) in a cohort of 667 adults with chronic hepatitis C virus (HCV) infection from a community‐based population in Japan, between 1994 and 2003. Cox proportional hazards regression analysis was used to describe the relationship between prediagnostic levels of ALT and the rate of HCC, after adjusting for age and gender; hazard ratios (HRs) and 95% confidence intervals (CIs) were obtained. Over an average of 8 years of follow‐up, 52 HCC cases were identified. A significant association between a 20 IU/L difference in higher ALT level and subsequent HCC incidence was observed (HR = 1.2; 95% CI: 1.1, 1.3). An abnormal ALT level (≥35 IU/L) increased the HCC rate by 4‐fold compared to a normal ALT level (HR = 4.1; 95% CI: 2.1, 8.0). Among 551 subjects with at least 4 repeated measurements of ALT, those with persistently abnormal ALT levels (n = 118) had a strong, significantly increased HCC rate compared to those with persistently normal ALT levels (n = 296) (HR = 23.2; 95% CI: 3.0, 178.5). This study demonstrates that elevated ALT levels, measured on an average of 8 years before HCC diagnosis, predict an increased rate of HCV‐associated HCC in a community‐based population and that utilizing serial measurements to identify persistent ALT abnormality may be useful in determining HCC risk.

Usefulness of a new immuno‐radiometric assay to detect hepatitis C core antigen in a community‐based population

Summary.  A new immuno‐radiometric assay (IRMA) to detect hepatitis C virus (HCV) core antigen (HCVcAg) has been developed. The aim of the present study was to investigate the sensitivity and specificity of this IRMA to measure HCV antigenemia, based on the detection of HCV RNA as the gold standard, and to assess the utility of the IRMA in a community‐based population. Anti‐HCV positive residents in a hyperendemic area of HCV infection in Japan were studied. Serum levels of HCVcAg were measured using IRMA, and the presence of HCV RNA was determined by a qualitative reverse transcription‐polymerase chain reaction (RT‐PCR) assay. The sensitivity and the specificity of the IRMA were 96.4 and 100%, respectively. The sensitivity of the IRMA was similar between serological HCV group I (HCV genotypes 1a and 1b) (97.6%) and group II (HCV genotypes 2a and 2b) (94.0%). There was a strong correlation between serum HCVcAg level and HCV‐RNA measured by a quantitative RT‐PCR (r = 0.832, P < 0.0001). There also was a very strong correlation of HCVcAg level between IRMA measurements performed on serum and those performed on plasma (r = 0.984, P < 0.0001). In conclusion, this new IRMA is useful for the detection of HCV core antigen in a community‐based population.

Impact of antibody to hepatitis B core antigen on the clinical course of hepatitis C virus carriers in a hyperendemic area in Japan: A community-based cohort study

Subjects positive for antibody to hepatitis B core antigen (HBcAb) and negative for hepatitis B surface antigen (HBsAg) are considered to have occult hepatitis B virus (HBV) infection. The aim of this study was to determine the impact of occult HBV infection on aggravation of the clinical course in hepatitis C virus (HCV) carriers.

Alanine aminotransferase flare-up in hepatitis C virus carriers with persistently normal alanine aminotransferase levels in a hyperendemic area of Japan.

BackgroundThe clinical features of hepatitis C virus (HCV) carriers with persistently normal alanine aminotransferase (PNALT) levels (ALT ≤ 34 IU/l) have not been fully elucidated. We investigated clinical factors associated with ALT flare-up in PNALT individuals in a HCV hyperendemic area of Japan.MethodsWe analyzed 101 HCV carriers who had PNALT between 1993 and 2000. The first occurrence of ALT flare-up (ALT ≥ 35 IU/l) between 2001 and 2005 was evaluated by the Kaplan-Meier method. Multivariate analysis of factors predicting ALT flare-up were conducted using Cox proportional hazards models.ResultsThe mean follow-up period was 2.8 years, and the 5-year cumulative incidence of ALT flare-up was estimated to be 31.8%. In multivariate analysis, an ALT level of 20–34 IU/l and a high serum ferritin level (≥90 ng/ml) in the most recently available data up to the year 2000, as well as H63D heterozygosity in the HFE gene, were independently and strongly associated with the incidence of ALT flare-up (Hazard ratios = 5.6, 3.1, and 4.8, respectively). In addition, HFE H63D heterozygosity was significantly associated with higher serum ferritin levels in subjects with PNALT (153.8 ± 73.3 ng/ml in subjects with the 63HD genotype vs. 89.4 ± 51.3 ng/ml in subjects with the 63HH genotype, P = 0.043).ConclusionsHCV carriers with PNALT in this population were at risk for ALT flare-up. Basal ALT levels, serum ferritin levels, and HFE polymorphism are potentially important predictors of ALT flare-up.

Impact of a single nucleotide polymorphism upstream of the IL28B gene in patients positive for anti‐HCV antibody in an HCV hyperendemic area in Japan

The influence of genetic variation at the interleukin‐28B (IL28B) locus on the natural course of hepatitis C virus (HCV) infection has not been fully investigated. The goal of this study was to examine whether an IL28B polymorphism (rs8099917) is associated with natural clearance of HCV and with disease parameters of HCV infection in an HCV hyperendemic area of Japan. The patients were 502 anti‐HCV antibody‐positive residents who participated in liver disease screening program from 2002 to 2004. Patients who underwent interferon‐based therapy or had hepatocellular carcinoma were excluded. Of these patients, 149 were negative for HCV RNA (prior infection) and 353 were positive for HCV RNA or HCV core antigen (HCV carriers). In multivariate analysis, the IL28B TT genotype was a predictor for prior HCV infection. In addition, nine of the patients with prior HCV infection were positive for anti‐HCV antibody with positive for HCV core antigen or HCV RNA before 2001, and these nine patients all had the IL28B TT genotype. Furthermore, the IL28B TT genotype was associated independently with higher HCV core antigen levels in HCV carriers. In contrast, the IL28B genotype did not affect the biochemical markers, such as alanine aminotransferase, hepatic fibrosis markers, and α‐fetoprotein, and the degree of hepatic fibrosis assessed by transient elastography in HCV carriers. We concluded that IL28B polymorphism (TT genotype) is associated with spontaneous clearance of HCV and conversely with high viral loads in HCV carriers. In contrast, the IL28B genotype does not affect disease progression such as hepatic fibrosis. J. Med. Virol. 86:1877–1885, 2014.

Efficacy and safety of sofosbuvir and ledipasvir in Japanese patients aged 75 years or over with hepatitis C genotype 1

AIM To evaluate the efficacy and safety of a regimen containing sofosbuvir (SOF) and ledipasvir (LDV) in Japanese patients aged ≥ 75 years with hepatitis C genotype 1. METHODS This multicenter, retrospective study consisted of 246 Japanese patients with HCV genotype 1 at nine centers in Miyazaki prefecture in Japan. Demographic, clinical, virological, and adverse effects (AE)-related data obtained during and after SOF/LDV therapy were collected from medical records. These patients were divided into two groups, younger (aged < 75 years) and elderly (aged ≥ 75 years). Virological data and AEs were analyzed by age group. RESULTS The sustained virological response (SVR) rates at 12 wk after treatment were 99.2%, 99.4%, and 98.7% in the overall population and in patients aged < 75 and ≥ 75 years, respectively. Common AEs during therapy were headache, pruritus, constipation, and insomnia. These occurred in fewer than 10% of patients, and their incidence was not significantly different between the younger and elderly groups. Two patients discontinued treatment, one due to a skin eruption and the other due to cerebral bleeding. CONCLUSION Compared with younger patients, elderly patients had a similar virological response and tolerance to SOF/LDV therapy.

Prediction of Sustained Virological Response to Telaprevir/Simeprevir-Based Triple Therapy in Patients with Genotype 1 Hepatitis C Virus Using Super-Early Viral Response within 2 Weeks

Objective: Rapid virological response (RVR), defined as undetectable serum hepatitis C virus (HCV) RNA at week 4, is a useful predictor of sustained virological response (SVR) to peginterferon (PEG-IFN) plus ribavirin (RBV) therapy and protease inhibitor (telaprevir (TVR)/simeprevir (SMV)) based triple therapy for patients infected with genotype 1 HCV. The aim of this study was to predict SVR using viral response within 2 weeks of therapy initiation. Methods: Fifty-two HCV genotype 1b patients with high viral loads treated with protease inhibitor (TVR/SMV)- based triple therapy were analysed. Thirty-seven patients were treated with TVR-based triple therapy and 15 with SMV-based triple therapy. HCV RNA levels were measured at the following points: the day of therapy initiation, at days 1 and 3, and at weeks 1 and 2. Results: SVR was achieved in 87% (45/52) of patients. There was no difference in SVR rate between the TVRbased triple therapy group (92%) and the SMV-based triple therapy group (73%) (P=0.1726). Univariate analysis of contributors to SVR showed a significant effect of liver fibrosis, platelet count, aspartate transaminase, α-fetoprotein in terms of pre-treatment factors, and HCV RNA load at week 2, reduction of HCV RNA at day 1 and week 2, RVR, and PEG-IFN adherence in terms of on-treatment factors. By multivariate analysis, platelet count and HCV RNA load at week 2 were independently associated with high SVR rate. Conclusion: HCV RNA level at week 2 was the most useful predictor of SVR after TVR/SMV-based triple therapy in patients with genotype 1 HCV.

Association of a genetic polymorphism in ectonucleotide pyrophosphatase/phosphodiesterase 1 with hepatitis C virus infection and hepatitis C virus core antigen levels in subjects in a hyperendemic area of Japan.

BackgroundThe clinical course of chronic hepatitis C virus (HCV) infection is strongly associated with insulin resistance and obesity. The K121Q polymorphism in the ectonucleotide pyrophosphatase/phosphodiesterase (ENPP)-1 gene and the rs7566605 genotype located near insulin-induced gene 2 have been shown to be associated with insulin resistance and obesity. This study examined whether the K121Q polymorphism in ENPP1 or the rs7566605 genotype is associated with the clinical course of HCV infection.MethodsThe relationships between the clinical characteristics of 469 anti-HCV antibody-seropositive subjects (353 were positive for HCV core antigen or RNA, whereas 116 were negative for HCV RNA) and the polymorphisms were analyzed.ResultsNo significant differences in body mass index, plasma glucose level, serum insulin level, and other biochemical markers were observed between subgroups of subjects with different genotypes at the K121Q polymorphism or rs7566605. The frequency of the homozygous wild-type genotype at K121Q in HCV carriers, however, was significantly higher than that in subjects who were negative for HCV RNA (84.5% vs. 75.9%; P < 0.05). Moreover, in HCV carriers, HCV core antigen levels in subjects homozygous for the wild-type genotype at K121Q were significantly higher than in heterozygous carriers of K121Q (5358 fmol/l vs. 4002 fmol/l; P = 0.04). In contrast, the rs7566605 genotype was not associated with hepatitis C viremia or with the HCV core antigen level.ConclusionsThe K121Q variant of ENPP1 may be associated with hepatitis C viremia and core antigen levels in HCV carriers.