Nobukazu Yuki

Hepatitis C virus antibody and hepatitis C virus replication in chronic hepatitis B patients

We assessed hepatitis C virus infection in 156 chronic hepatitis B patients using second-generation hepatitis C virus antibody (anti-HCV). Active virus replication was further investigated in anti-HCV-positive cases by means of polymerase chain reaction assay for the detection of serum hepatitis C virus RNA. Anti-HCV prevalence was higher in patients negative for hepatitis B e antigen (HBeAg) (10/48, 21%) than in HBeAg-positive patients (10/108, 9%) (p < 0.05), and the reactivity (cut-off index) in anti-HCV enzyme-linked immunosorbent assay of the positive cases was significantly higher in HBeAg-negative patients (4.1 +/- 0.1) than in -positive ones (3.6 +/- 0.6) (p < 0.05). The prevalence of hepatitis C virus RNA in anti-HCV-positive cases was also higher in the HBeAg-negative group (9/10, 90%) than in the -positive group (3/10, 30%) (p < 0.01). Viremia was found in association with high reactivity in anti-HCV ELISA (cut-off index > 3.5) in both groups. Nine (90%) of 10 such cases were viremic in the HBeAg-negative group compared with three (43%) of seven in the HBeAg-positive group (p < 0.05). These results suggest that hepatitis C virus replication may be influenced by hepatitis B virus replicative states, indicating possible interference between hepatitis B and C viruses.

Detection of Hepatitis C Virus RNA in Chronic Non-A, Non-B Liver Disease

Serum samples were tested for detection of hepatitis C virus (HCV) RNA from 156 patients with chronic non-A, non-B liver disease. HCV RNA was detected in 121 (93.8%) of 129 patients positive for anti-C100-3 but was also found in 15 (55.6%) of 27 patients negative for anti-C100-3. The rate of positivity for HCV RNA was not significantly different among various stages of liver diseases. These results showed that HCV continues to replicate even in advanced liver disease and that it seems to be related to half of the cases of chronic non-A, non-B liver disease negative for anti-C100-3.

Pretreatment viral load and response to prolonged interferon-α course for chronic hepatitis C

Abstract Background/Aims: We investigated the clinical benefit of long-term interferon therapy in chronic hepatitis C in relation to the pretreatment viral load and genotypes. Methods: Chronic hepatitis C patients were randomly assigned to receive 28-week (n=45) or 52-week (n=43) courses of interferon-α. The responses were correlated with pretreatment viremic levels assessed by a branched DNA assay and genotypes. Results: After the 28-week interferon-α course, sustained aminotransferase normalization showed correlation with a lower initial viral load. The normalization was achieved by 78% (79) of the low viremic (branched DNA-negative) patients, but only 22% (836) of the highly viremic (branched DNA-positive) patients ( p p Conclusions: These findings suggest that although the pretreatment viral load is an important virological factor for predicting responses to interferon in chronic hepatitis C, relapse in highly viremic patients may be prevented by long-term therapy.

Hepatitis B virus markers and antibodies to hepatitis C virus in Japanese patients with hepatocellular carcinoma

Sera from Japanese patients with chronic liver disease were tested for hepatitis B virus (HBV) markers and antibodies to hepatitis C virus (anti-HCV), and the results were correlated to the presence of hepatocellular carcinoma. In chronic non-A, non-B liver disease, anti-HCV prevalence was high both in patients with hepatocellular carcinoma (78/89, 88%) and without it (66/84, 79%), while previous HBV infection was more common in patients with hepatocellular carcinoma (65/89, 73%) than in those without it (46/84, 55%) (P<0.05). Coexistence of anti-HCV and antibodies to HBV was observed frequently in patients with hepatocellular carcinoma (56/89, 63%) compared with patients without it (39/84, 46%) (P<0.05). In chronic HBV carriers, anti-HCV was more common in patients with hepatocellular carcinoma (12/38, 32%) than in those without it (3/62, 5%) (P<0.01). These results suggest that infection with the two viruses may be a risk factor for more serious liver disease.

Long-term clinical impact of occult hepatitis B virus infection in chronic hepatitis B patients

BACKGROUND/AIMS Long-term clinical outcomes of occult hepatitis B virus (HBV) infection were studied. METHODS Fifteen chronic hepatitis B patients were monitored for a median of 4.4 years (range 0.9-15.3) after hepatitis B surface antigen (HBsAg) seroclearance. Serum HBV DNA was measured by real-time detection polymerase chain reaction. Thirteen patients underwent liver biopsies at the end of follow-up and liver histology was evaluated by Ishak score. Liver HBV DNA was also measured for 12 patients. RESULTS At the end of follow-up, HBV viremia was absent in 13 (87%) patients, and antibody titers to hepatitis B core antigen showed an inverse correlation with time from HBsAg seroclearance (r=-0.554; P=0.0040). However, all patients retained liver HBV DNA and tested positive for the covalently closed circular HBV DNA replicative intermediate. The hepatic HBV DNA loads had no relation to liver histology. Paired biopsies from 11 patients disclosed that each necroinflammatory score significantly improved after HBsAg seroclearance. Amelioration of liver fibrosis was also evident in eight (73%) patients (P=0.0391 by signed rank test). CONCLUSIONS A long-standing but strongly suppressed HBV infection may confer histological amelioration after HBsAg seroclearance.

Clinical implications of coinfection with a novel DNA virus (TTV) in hepatitis C virus carriers on maintenance hemodialysis

A novel hepatitis‐associated DNA virus, designated as transfusion‐transmitted virus (TTV), was identified recently. We investigated the frequency of TTV viremia in hepatitis C virus (HCV) carriers on maintenance hemodialysis to determine whether TTV coinfection has any clinical relevance. The subjects were 50 hemodialysis patients who had been followed over 4 years after diagnosis of HCV infection. Stored serum samples derived from each patient every 12th month after enrollment were subjected to polymerase chain reaction to amplify TTV DNA and HCV RNA. At enrollment, TTV viremia was detected in 24 (48%) HCV‐positive patients irrespective of the number of previous blood transfusions and the duration of hemodialysis. The presence of TTV viremia had no relation to serum alanine aminotransferase (ALT) levels, HCV viremic levels or HCV genotypes. After enrollment, HCV infection persisted in all patients over the 4‐year follow‐up period, whereas spontaneous resolution of TTV infection was observed in 7 (29%) of the 24 TTV viremic cases (annual rate 7.3%, 95% confidence interval [CI] 0.8–25.5%). Evidence for TTV infection was found in 4 (15%) of the 26 TTV nonviremic patients (annual incidence 3.9%, 95% CI 0.1–19.6%). The relationship between the ALT profile and TTV infection during follow up was not evident. Active TTV coinfection occurs frequently in HCV carriers undergoing hemodialysis but exerts no biochemical or virological influence on the underlying hepatitis C. Lack of disease association and the frequent spontaneous resolution of infection suggest that the clinical significance of TTV infection remains unclear. J. Med. Virol. 59:431–436, 1999.

Reappraisal of Biochemical Hepatitis C Activity in Hemodialysis Patients

We reappraised biochemical hepatitis C activity in hemodialysis patients in comparison with normal controls. A total of 111 hemodialysis patients and 66 healthy volunteer blood donors with hepatitis C virus (HCV) infection were consecutively enrolled. Serum alanine aminotransferase (ALT) levels were normal (< or =45 U/L) in 103 (93%) hemodialysis patients and 34 (52%) donors (p < 0.001). HCV viremic levels were lower in the hemodialysis group (p = 0.044), with no difference in the HCV genotype prevalence. During two-year follow-up, 60 (67%) of 90 hemodialysis patients and 13 (26%) of 50 donors showed persistently normal ALT levels (p < 0.001). For hemodialysis patients, however, the upper normal limit of ALT activity was reset at 25 U/L corresponding to the mean + 2 x SD for the normalized ALT distribution in 400 control patients. The adjusted ALT levels were initially normal in 73 (66%) hemodialysis patients and persistently normal in 19 (21%). Thus, ALT levels were the same for the two groups. GB virus C (GBV-C)/hepatitis G virus (HGV) coinfection found only in the hemodialysis group (10/111) had no influence on the disease. A relationship was noted between low disease activity and female gender in both groups. These findings indicate that biochemical hepatitis C activity in hemodialysis patients is similar to that in normal controls and should be monitored based on adjusted ALT levels.

The significance of immunoglobulin M antibody response to hepatitis C virus core protein in patients with chronic hepatitis C

The significance of immunoglobulin (Ig) M antibody to hepatitis C virus core protein (IgM anti‐HCVcore) was studied in 41 patients with chronic hepatitis C virus (HCV) infection diagnosed by the polymerase chain reaction (PCR). IgM anti‐HCVcore was tested with a solid‐phase enzyme‐linked immunoassay. The results were correlated with clinical features, liver histology findings evaluated by the histological activity index, and virological features such as genotypes and viremic levels assessed by a branched DNA assay. IgM anti‐HCVcore was found in 29 (71%) patients, and its occurrence was only related to viremic levels. A significant relationship was observed between viremic levels and IgM anti‐HCVcore cut‐off index (rs = .42, P < .01). Of the eight low viremic (branched DNA‐negative) patients, only two (25%) tested positive for IgM anti‐HCVcore with a low cut‐off index of <3, whereas 27 (82%) of the 33 highly viremic (branched DNA‐positive) patients had IgM anti‐HCVcore (P < .01). After a 28‐week interferon‐α course (IFN‐α), sustained aminotransferase normalization after therapy withdrawal was achieved by only two (13%) of the 16 patients with IgM anti‐HCVcore cut‐off index >3 compared with 11 (44%) of the 25 patients with that <3 (P < .05). IgM anti‐HCVcore cut‐off index decreased after therapy in patients who cleared the virus in sera but increased again after reappearance of viremia. These findings suggest that IgM anti‐HCVcore may serve as a simple serological indicator of active virus replication and have relevance to the outcome of antiviral therapy. (Hepatology 1995; 22:402–406.)

Serodiagnosis of chronic hepatitis C in Japan by second-generation recombinant immunoblot assay

The seroprevalence of antibodies to hepatitis C virus (HCV) by a second-generation recombinant immunoblot assay (RIBA-2) was tested using 4 recombinant antigens. The results were correlated with those of C100-3 enzyme-linked immunosorbent assay (ELISA) and with the detection of HCV-RNA sequences by the polymerase chain reaction. Sera were obtained from 27 C100-3 ELISA-positive Japanese patients with chronic non-A, non-B liver disease and from 29 C100-3 ELISA-negative patients. All C100-3 ELISA-positive patients and 19 (66%) out of 29 C100-3 ELISA-negative patients reacted to two or more RIBA-2 antigens (reactive by RIBA-2). Of the remaining 10 C100-3 ELISA-negative patients, one patient reacted to just one antigen (indeterminate by RIBA-2), while 9 reacted to none of the 4 antigens (non-reactive by RIBA-2). Forty-three (93%) of the 46 RIBA-2-reactive patients and the single RIBA-2-indeterminate patient tested positive for HCV-RNA sequences, whereas only one (11%) of the 9 RIBA-2-non-reactive patients tested positive. These findings indicate that HCV infection is more prevalent than expected from the results of C100-3 ELISA, and that RIBA-2 is a more sensitive assay for estimating the presence of HCV infection in chronic liver disease.

HCV RNA and antibody to HCV core protein in Japanese patients with chronic liver disease

We evaluated the prevalence of hepatitis C virus (HCV) RNA and antibody (anti-HCVcore) to the putative HCV core protein in Japanese patients with chronic liver disease. Sera were screened by solid-phase enzyme immunoassay with a recombinant HCV core protein and by the reverse transcription-polymerase chain reaction (RT-PCR) test which directly detects the HCV genome. Anti-HCVcore was detected with high titers in 95% (69/73) of chronic non-A, non-B hepatitis, and 94% (65/69) of anti-HCVcore-positive patients had the genome. Anti-HCVcore was also found with lower titers in 24% (10/41) of chronic hepatitis B virus carriers, and three of them had the genome. Only one (3%) of the 35 patients negative for anti-HCVcore tested positive to RT-PCR. These findings indicate the overwhelming prevalence of HCV infection in Japanese patients with chronic non-A, non-B hepatitis and a close relationship between the presence of anti-HCVcore and chronic hepatitis C in this population.