Hepatitis B surface antigen reduction by switching from long-term nucleoside/nucleotide analogue administration to pegylated interferon.

Hepatitis B surface antigen (HBsAg) reduction during nucleoside/nucleotide analogue (NA) therapy is slow and an alternative strategy for patients receiving ongoing NA to facilitate HBsAg reduction is required. We investigated whether switching to pegylated interferon (PEG-IFN) after long-term NA administration enhances HBsAg reduction. Forty-nine patients who switched from long-term NA to 48 weeks of PEG-IFN alfa-2a were studied. The mean duration of previous NA was 48 months (sequential group). A total of 147 patients who continued NA and matched for baseline characteristics were analysed for comparison (NA continuation group). The treatment response was defined as HBsAg reduction ≥1.0 logIU/mL at the end of PEG-IFN. HBsAg reduction at week 48 was 0.81±1.1 logIU/mL in the sequential group, which was significantly higher than that in the NA continuation group (0.11±0.3 logIU/mL, P < .001). The treatment response was achieved in 29% and 2% of the sequential group and NA continuation group (P < .001), and the odds ratio of sequential therapy for the treatment response was 19 compared with the NA continuation (P < .001). In patients tested positive for hepatitis B e antigen (HBeAg), HBeAg seroconversion was higher in the sequential group (44% vs 8%, P < .001). In HBeAg-negative patients, only patients in the sequential group achieved HBsAg loss. No patient needed to resume NA administration because of HBV DNA increase accompanied by alanine aminotransferase flares. In summary, sequential therapy with PEG-IFN after long-term NA enhances the reduction of HBsAg and may represent a treatment option to promote HBsAg loss.

ITPA genetic variants influence efficacy of PEG-IFN/RBV therapy in older patients infected with HCV genotype 1 and favourable IL28B type.

Inosine triphosphatase (ITPA) genetic variants are strongly associated with ribavirin (RBV)-induced anaemia during pegylated interferon (PEG-IFN) plus RBV therapy. However, the treatment efficacy of ITPA genetic variants has not been fully explored. We enrolled 309 individuals infected with hepatitis C virus genotype 1, who were treated with PEG-IFN plus RBV for 48 weeks. The ITPA SNP: rs1127354 and IL28B SNP: rs8099917 were genotyped. We examined the risk factors for severe anaemia up to week 12 after the start of treatment and treatment efficacy. The incidence of severe anaemia, ≥ 3 g/dL reduction or <10 g/dL of haemoglobin (Hb) up to week 12, was more frequent in patients with CC at rs1127354 [65% (145/224), 33% (73/224)] than in those with CA/AA [25% (21/85), 6% (8/85)] (P < 0.0001). ITPA genotype, pretreatment Hb level and age were independent predictive factors for severe anaemia: Hb < 10 g/dL. In IL28B favourable type, the sustained virologic response rate was higher in ≥ 60-year-old patients with CA/AA than in those with CC [71% (22/31) vs 40% (26/65), P = 0.005], although there was no significant difference in treatment efficacy according to ITPA genetic variants in the <60-year-old patients. The proportion of patients administered ≥ 80% of the dosage of RBV was significantly higher in the patients with CA/AA than in those with CC (P = 0.025), resulting in a lower relapse rate. In conclusion, ITPA genetic variants were associated with severe RBV-induced anaemia and could influence the efficacy of PEG-IFN plus RBV treatment among elderly patients with IL28B favourable type.

Preoperative drainage using a transanal tube enables elective laparoscopic colectomy for obstructive distal colorectal cancer.

BACKGROUND AND STUDY AIMS: Acute colorectal obstruction (ACO) often accompanies colorectal cancer (CRC) and requires urgent treatment, but achieving elective laparoscopy-assisted colectomy (LAC) is difficult in this setting. The aim of the current study was to assess the clinical outcomes of a transanal tube (Dennis colorectal tube [DCT]) for CRC with ACO, focusing in particular on the impact of the DCT on subsequent elective LAC. PATIENTS AND METHODS: Among 1142 patients who underwent surgery for CRC between January 2007 and December 2011, 92 patients with ACO were identified retrospectively. Of these 92 patients, the DCT procedure was performed in 66 patients who fulfilled the indications for DCT, and these patients were included in the study. RESULTS: All 66 patients presented with complete obstruction. Technical and clinical success rates for DCT were 93.9 % and 86.4 %, respectively. Perforation after DCT occurred in 4.5 % and the mortality rate was 1.5 %. The rate of LAC was 48.5 %, and the rate of primary stoma was 13.6 %. For curative stage II/III CRC with ACO, DCT resulted in a primary stoma rate of 13.6 %, a one-stage surgery rate of 90.9 %, a LAC rate of 50.0 %, and a 3-year survival rate of 73.1 %. For stage II/III CRC cases with clinical success by DCT, the one-stage surgery rate was 97.4 % and the LAC rate was 56.4 %. CONCLUSIONS: DCT achieved a high rate of clinical success and enabled safe one-stage surgery and LAC for CRC with ACO. DCT followed by LAC is proposed as a promising non-invasive strategy for CRC with ACO.

Constrained genomic and conformational variability of the hypervariable region 1 of hepatitis C virus in chronically infected patients.

We analysed the genomic and conformational variability of the hypervariable region 1 (HVR1) of the hepatitis C virus (HCV) to evaluate the importance of its biological role. A total of 865 genotype 1b HVR1 subclones were collected from serially sampled sera in 11 patients with chronic hepatitis C, four of whom received interferon therapy. Consequently, 169 distinct sequences were examined for amino acid substitutions as well as hydrophilic or hydrophobic profile at each amino acid position within HVR1. Secondary structure of HVR1 was also predicted by the method of Robson in 90 distinct sequences from eight patients, including three interferon-treated patients. Some positions within the HVR1 were invariable or nearly so as to amino acid substitution. Hydrophilic or hydrophobic residues exclusively predominated at several positions. These constrained amino acid replacement and hydrophilic or hydrophobic profiles were conserved irrespective of interferon therapy, though the frequency of amino acid replacement was greater at almost all amino acid positions within the HVR1 in interferon-treated patients. The quasispecies of HCV showed various secondary structures of HVR1, but many sequences seemed to have common characteristics. beta sheet conformations around both the N-terminus and position 20 (numbered from the NH2 terminus of E2 envelope glycoprotein), and/or coil structures around the C-terminus of HVR1 could be identified. These results suggest that HVR1 amino acid replacements are strongly constrained by a well-ordered structure, in spite of being tolerant to amino acid substitutions, and imply an important biological role of the HVR1 protein in HCV replication.

Biochemical response to interferon therapy correlates with interferon sensitivity-determining region in hepatitis C virus genotype 1b infection.

Biochemical responders maintain normal alanine aminotransferase levels after interferon (IFN) therapy despite persistent presence of hepatitis C virus (HCV) RNA in their sera. There have been few reports on predictive factors for biochemical response. A region associated with sensitivity to IFN was identified in the nonstructural protein 5 A of genotype 1b [aa 2209-2248; IFN sensitivity-determining region (ISDR)]. The substitutions in ISDR correlate with sustained response to IFN. In this report, we assessed the association of ISDR with biochemical response. The sequences of ISDR were determined in 62 patients with HCV genotype 1b treated by IFN in two randomized controlled trials. 30 patients had wild ISDR (identical to HCV-J), 20 intermediate ISDR (1-3 amino acid substitutions compared with HCV-J), and 12 mutant ISDR (four or more amino acid substitutions). All 12 patients with mutant ISDR had a sustained response, while only one of those with wild or intermediate ISDR had a sustained response (P < 0.0001). In the 49 patients other than sustained responders, the patients with intermediate ISDR obtained biochemical response significantly more frequently (52.6%, 10/19) than those with wild-type ISDR (20.0%, 6/30) (P < 0.05). Multivariate analysis indicated the number of substitutions in ISDR as the most important predictor for biochemical response (discriminant coefficient=1.08, P < 0.05) and sustained response (discriminant coefficient=6.13, P < 0.0001). In phylogenetic analysis, clustering of sustained responders and biochemical responders was observed. These results demonstrate that the substitutions in ISDR are the most important predictor for biochemical response to IFN in patients infected with genotype 1b as well as for sustained response.

Determination of hepatitis B virus genotype G by polymerase chain reaction with hemi-nested primers.

Hepatitis B virus (HBV) has been classified into six genotypes designated A-F by sequence divergence in the entire genome exceeding 8%. Very recently, the seventh genotype was reported and named genotype G. HBV genotype G is distinct from genomes of the other six genotypes in that it possesses an insertion of 36 nucleotides in the core gene, and has been found so far in France and the United States. A method for determining HBV genotype G was developed by polymerase chain reaction (PCR) with primers deduced from the 36-nucleotide (nt) insertion in five isolates of HBV genotype G the sequences of which have been deposited in DNA databases. The validity of this method, for specifically detecting HBV genotype G, was verified on a panel consisting of 142 HBV isolates of six major genotypes and four of genotype G. A total of 540 sera containing HBV in Japan covering symptom free carriers and patients with a spectrum of chronic liver disease were tested by this method, but not a single HBV genotype G sample was found. A possible method for serological determination of hepatitis B surface antigen of genotype G is suggested, without amplification or sequencing nucleotides, which would expand epidemiological and clinical researches on HBV genotype G.

Geographic distribution of hepatitis B virus (HBV) genotype in patients with chronic HBV infection in Japan.

The geographic distribution of hepatitis B virus (HBV) genotypes in Japan and its clinical relevance are poorly understood. We studied 731 Japanese patients with chronic HBV infection. HBV genotype was determined by the restriction fragment length polymorphism (RFLP) method after polymerase chain reaction (PCR). Of the 720 patients with positive PCR, 12 (1.7%) were HBV genotype A, 88 (12.2%) were genotype B, 610 (84.7%) were genotype C, 3 (0.4%) were genotype D, and 7 (1.0%) were of mixed genotype. Over 94% of patients on the Japanese mainland had genotype C, while 60% of the patients on Okinawa, the most southern islands, and 22.9% in the Tohoku area, the northern part of the mainland, harbored genotype B. Compared with genotype C patients, genotype B patients were older (53.6 to 42.2 years; P <.01), had a lower rate of positive hepatitis B e antigen (HBeAg) (18.4% to 50.6%; P <.01), and a lower level of serum HBV DNA (5.02 to 5.87 log genome equivalents (LGE)/mL; P <.01). The mean age of the genotype B patients with hepatocellular carcinoma was 70.1 +/- 9.2 years, compared with 55.2 +/- 9.7 of genotype C patients (P <.01). These results indicate that genotypes C and B are predominant in Japan, and there are significant differences in geographic distribution and clinical characteristics among the patients with the different genotypes.

[HCV genotype as a predictor of response to interferon therapy in patients with chronic hepatitis C].

Hepatitis C virus(HCV) genotype is one of the most important predicting factors of response to interferon(IFN) therapy in patients with chronic hepatitis C. According to the molecular evolutionary analysis, HCV is classified into six major genotypes. The patients infected with genotype 1 show high HCV RNA levels and poor response to IFN therapy compared to those with genotype 2 or 3. No sufficient data are observed on response to IFN in patients with genotype 4 to 6. When PEG-IFN plus ribavirin therapy is introduced, high proportion of patients without genotype 1 must show complete response. In the near future, to predict good response to IFN therapy, it will be necessary to know whether patients have HCV genotype 1 or not.

Effect of interferon therapy on Japanese chronic hepatitis C virus patients with anti-liver/kidney microsome autoantibody type 1.

AIM: The aim of this study was to determine the prevalence of anti-liver/kidney microsome autoantibody type 1 (anti-LKM-1) among hepatitis C virus (HCV)-infected Japanese patients at various stages (chronic hepatitis, liver cirrhosis and hepatocellular carcinoma), and to assess the influence of anti-LKM-1 on interferon therapy. METHODS: A total of 390 serum samples from 215 HCV-infected patients with chronic hepatitis (HCV-CH), 81 HCV-infected patients with liver cirrhosis (HCV-LC), and 94 HCV-HCC infected patients were subjected to examination. Ninety-one HBsAg-positive patients and 137 healthy subjects served as controls. Anti-liver/kidney microsome autoantibody type 1 was determined by using a newly developed ELISA using recombinant cytochrome P450 IID6 as the antigen. RESULTS: Anti-liver/kidney microsome autoantibody type 1 was detected in six of the 390 (1.5%) chronic HCV-infected patients (four were HCV-CH and two were HCV-LC); in contrast, it was not detected in control groups. Among the 110 HCV-CH patients treated with interferon (IFN), four were positive for anti-LKM-1. No change in anti-LKM-1 immunoreactivity from negative to positive during interferon therapy was observed. Moreover, no increase in the serum alanine aminotransferase level was observed in these four patients with anti-LKM-1. CONCLUSION: Our study indicates that: (i) anti-LKM-1 does not aggravate the liver disease associated with HCV infection; and (ii) no change in anti-LKM-1 immunoreactivity from negative to positive or no aggravations of liver dysfunction were observed among HCV-CH patients during the IFN therapy for Japanese patients with liver disease.

Hepatitis B virus genotype distribution among chronic hepatitis B virus carriers in Shanghai, China.

OBJECTIVE: Hepatitis B virus (HBV) genotype distribution is still unclear in China, where a high prevalence of HBV infection exists, although it is well known that HBV can be classified into six genotypes based on intergroup divergence. The aim of this study was to investigate the epidemiological distribution of HBV genotypes and to clarify further the genotype-related differences in the pathogenicity of HBV. METHODS: Seminested PCR and restriction fragment length polymorphism analysis were conducted in 97 asymptomatic HBV carriers (ASC) and 46 chronic hepatitis (CH), 37 liver cirrhosis (LC) and 44 hepatocellular carcinoma (HCC) patients in Shanghai, China. RESULTS: Two hundred and twenty samples (98.2%) were positive for HBV DNA, and of these, 3 (1.4%), 38 (17.2%) and 179 (81.4%) were classified as genotype A, B and C, respectively. There was a statistically significant difference in the distribution of genotypes B and C among various categories of liver diseases (p < 0.01). The distribution of genotype C showed an increasing trend from ASC, CH and LC to the HCC group; in contrast, the distribution of genotype B showed a decreasing trend in the same order. HBeAg positivity was higher in genotype C than in genotype B in all the subjects or in the ASC group alone (p < 0.05, p < 0.01, respectively). More severe liver damage and a higher mean age were observed in genotype C than in genotype B (p < 0.01, p < 0.05, respectively). CONCLUSIONS: These results indicate the following: (1) genotypes A, B and C of HBV exist in Shanghai, China; (2) genotype C is the major genotype in this area; (3) genotype C is associated with the development of severe liver diseases, and (4) genotype B has a relatively good prognosis.

Evaluation of accumulation of hepatitis C virus mutations in a chronically infected chimpanzee: comparison of the core, E1, HVR1, and NS5b regions.

Four hepatitis C virus genome regions (the core, E1, HVR1, and NS5b) were amplified and sequenced from yearly samples obtained from a chronically infected chimpanzee over a 12-year span. Nucleotide substitutions were found to accumulate in the core, E1, and HVR1 regions during the course of chronic infection; substitutions within the NS5b region were not detected for the first 8 years and were found to be minimal during the last 4 years. The rate of accumulation of mutations in the core and E1 regions, based on a direct comparison between the first 1979 sequence and the last 1990 sequence, was 1.120 x 10(-3), while phylogenetic ancestral comparison using the 12 yearly sequences showed a rate of 0.816 x 10(-3) bases per site per year. Temporal evaluation of the sequences revealed that there appeared to be periods in which substitutions accumulated and became fixed, followed by periods with relative stasis or random substitutions that did not persist. Synonymous and nonsynonymous substitutions within the core, E1, and HVR1 regions were also analyzed. In the core and E1 regions, synonymous substitutions predominated and gradually increased over time. However, within the HVR1 region, nonsynonymous substitutions predominated but gradually decreased over time.

A case-control study for clinical and molecular biological differences between hepatitis B viruses of genotypes B and C. Japan HBV Genotype Research Group.

Clinical and molecular virological differences were evaluated in 50 Japanese patients chronically infected with HBV of genotype B and C who were matched for age and sex as well as the severity of liver disease in a case-control study. Hepatitis B e antigen (HBeAg) was significantly less frequent (16% vs. 42%, P <.01), whereas antibody to HBeAg (anti-HBe) was significantly more common (84% vs. 56%, P <. 01) in genotype B than C patients. The predominance of mutants with G-to-A mutation at nucleotide (nt) 1896 in the precore region (A1896) over the wild-type was comparable between genotype B and C patients (60% and 62%, respectively), and it correlated with anti-HBe. The double mutation in the basic core promoter (A-to-T at nt 1762 and G-to-A at nt 1764), however, was significantly more frequent in genotype C than B patients (58% vs. 16%, P <.01), and it did not correlate with anti-HBe or HBeAg. By the multiple logistic regression analysis, the double mutation in the basic core promoter (T1762/A1764) was significantly associated with genotype C [odds ratio (OR), 9.3; 95% confidence interval (CI), 3.4-25.1]], age > or = 35 years (OR, 5.5; CI, 1.5-20.5), and more advanced liver disease (OR, 4.1; CI, 1.6-10.2), but it was not associated with sex, HBeAg, HBV DNA, or the precore mutation (A1896). These results suggest a role of the double mutation in the basic core promoter in association with genotype C and a longer duration of infection in the aggravation of chronic hepatitis B.

Molecular evolutionary analysis of the complete nucleotide sequence of hepatitis B virus (HBV) in a case of HBV infection acquired through a needlestick accident.

To elucidate needlestick transmission of hepatitis B virus (HBV), strains isolated from 1 physician who acquired HBV infection through a needlestick accident and 3 patients with chronic hepatitis B (donor patients A, B, and C) were tested using molecular evolutionary analysis based on full-length HBV genomic sequences. Nucleotide sequences of these isolates were aligned with 55 previously reported full-length genomic sequences. Genetic distances were estimated using the 6-parameter method, and phylogenetic trees were constructed using the neighbor-joining method. Strains isolated from patient A and the recipient pair were clustered within a closer range of evolutionary distances than were strains recovered from the recipient pair and patients B and C. Furthermore, strains from patient A and the recipient were also clustered on the S gene sequences of HBV. These results demonstrated that patient A alone was the source of direct transmission to the recipient. This approach can be used to investigate the transmission route of HBV.

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.

Identification of a novel 23kDa protein encoded by putative open reading frame 2 of TT virus (TTV) genotype 1 different from the other genotypes.

We report the entire open reading frames (ORFs) sequences of four TT virus (TTV) isolates, one genotype 2 (G2) and three G4 isolates. Despite a DNA virus, TTV possesses high rate of amino acid (aa) substitution: the aa sequence homology of ORF1 and 2 is lower than the nucleotide homology. The partial 'N22' region of ORF1 is suitable for genotyping of 'prototype TTV' isolates, because the phylogenetic tree from partial 'N22' sequence is consistent with that from the entire ORF1. Based on our sequence data, ORF2 from most isolates excluding G1 encode truncated 49 aa (pORF2a) because of an in-frame stop codon, although ORF2s from most G1 isolates encode 202 aa (pORF2ab). Just downstream the stop codon, another ORF encoding a protein of approximately 150 aa (pORF2b) is found, whose homology is quite low among these genotypes. Our in vitro transcription/translation study supports that all G1a and a part of G b without an in-frame stop codon dominantly encode pORF2ab, a novel 23 kDa protein, whereas the other genotypes with an in-frame stop codon encode pORF2b (17 kDa). Our data indicate TTV G1a and a part of G1b should have different characteristics from the other genotypes.

Lack of association between TTV viral load and aminotransferase levels in patients with hepatitis C or non-B-C.

TT virus (TTV) is a newly identified un-enveloped single-stranded DNA virus. Although TTV was initially thought to be a new hepatitis virus, it is still unclear whether it causes hepatitis. To clarify the natural history and pathogenesis of TTV infection, serial serum samples from patients with chronic hepatitis were analysed. TTV DNA was quantified by real-time detection polymerase chain reaction assay (RTD-PCR), which was adapted for TTV. Five patients with chronic hepatitis, 4 with hepatitis C and 1 with non-B-C, were studied. The study period ranged from 9 to 50 months. In 3 patients there were frequent increases in TTV DNA titres, but no concomitant elevation of the aminotransferase (ALT) levels. In 2 patients who were treated with interferon, the changes in TTV titres were not synchronized with those of the ALT levels. Thus, in cases of chronic hepatitis, no correlation was observed between the serum TTV DNA titres and the ALT levels.

Lack of integrated TT virus (TTV) genomes in cellular DNA in infected human hematopoietic cells.

TT virus (TTV) isolated from the serum of a patient with posttransfusion hepatitis has been characterized as a member of the Circoviridae, a family of small DNA viruses with single-stranded circular genomes. TTV appeared to infect not only the serum and liver, but also the peripheral blood mononuclear cells (PBMC). We investigated the prevalence of TTV DNA in human hematopoietic cells, based on 84 mononuclear cell samples obtained from the bone marrow or lymph nodes of patients with hematopoietic malignancies including leukemia, malignant lymphoma and aplastic anemia. Forty-nine (58.3%) out of the 84 samples were positive for TTV DNA with polymerase chain reaction analysis, which was almost similar to the frequency found in the patients' serum. Southern blot analyses using a 3.2-kb fragment derived from the TTV DNA, however, showed no evidence supporting the fact that the TTV genomes are integrated into the human hematopoietic cell genomes, thus suggesting their existence as episomal forms.

TT virus infection in patients with chronic hepatitis C virus infection--effect of primers, prevalence, and clinical significance. Hepatitis Interventional Therapy Group.

BACKGROUND/AIM: A novel DNA virus, TT virus (TTV), was recently identified in patients with post-transfusion non-A-G hepatitis. The aim of this study was to determine the prevalence and clinical significance of TTV infection in patients with chronic hepatitis C virus (HCV) infection. METHODS: We analyzed pretreatment serum samples from 171 United States and European patients who relapsed after interferon-alpha treatment and were recruited into an interferon-alpha-2b/ribavirin combination treatment trial. TTV DNA was detected by PCR using two different set of primers (TTV-A and TTV-B) derived from open reading frames 1 and 2, respectively. RESULTS: TTV was detected in 29.2% of the patients with the TTV-A primer set, 70.8% with the TTV-B primer-set, and 72.5% if positive by either/both sets of the primers. The amplicons generated by primer set A were sequenced and a phylogenetic tree was constructed. The 50 isolates belonged to group la (n=8), 1b (n=17), 2a (n=21), 2b (n=3), and 4 (n=1). There was no difference in demographic (age, sex distribution, estimated duration of HCV infection), biochemical (serum ALT levels), virologic (serum HCV RNA levels, HCV genotype distribution), or histologic scores, and their subsequent response to either interferon-alpha-2b or interferon-alpha-2b/ribavirin combination treatment. CONCLUSIONS: The prevalence of TTV infection reported previously may have been significantly underestimated, based on the primers originally described and used by most studies. Although TTV infection is very common in patients with chronic HCV infection, it has no identifiable clinical significance.

Development of a TT virus DNA quantification system using real-time detection PCR.

Although TT virus (TTV) was isolated from a cryptogenic posttransfusion hepatitis patient, its pathogenic role remains unclear. It has been reported that the majority of the healthy population is infected with TTV. To elucidate the differences between TTV infection in patients with liver diseases and TTV infection in the healthy population, a quantification system was developed. TTV DNA was quantified by a real-time detection PCR (RTD-PCR) assay on an ABI Prism 7700 sequence detector. With this system, TTV DNA was quantified in 78 hepatitis C virus (HCV)-infected patients (63 with elevated serum alanine aminotransferase [ALT] levels and 15 with normal ALT levels) and in 70 voluntary blood donors (BDs). The quantification range was 2.08 to 7.35 log copies/ml. The intra-assay and interassay coefficients of variation were 0.37 to 6.33% and 0.60 to 7.07%, respectively. The mean serum TTV DNA levels in the HCV-infected patients with both elevated and normal ALT levels and BDs were 3.69 +/- 0.89, 3.45 +/- 0.76, and 3.45 +/- 0.67 log copies/ml, respectively. Comparison of the serum TTV DNA levels among the HCV-infected patients revealed that they were not related to the serum ALT and HCV core protein levels or to the histopathological score on liver biopsy. This study showed that (i) the RTD-PCR assay for the detection of TTV was accurate and had a high degree of sensitivity, (ii) the mean serum TTV DNA level was similar among HCV-infected patients, irrespective of their ALT level, and also among BDs, and (iii) a high serum TTV DNA level does not affect the serum ALT and HCV levels or liver damage in HCV-infected patients.

Quantification of serum HCV core antigen by a fluorescent enzyme immunoassay in liver transplant recipients with recurrent hepatitis C--clinical and virologic implications.

BACKGROUND: Monitoring hepatitis C viremia may be useful in the management of liver transplant patients with recurrent hepatitis C virus (HCV) infection. The clinical utility of a newly described fluorescent enzyme immunoassay for the detection of serum HCV core antigen was evaluated. METHODS: Serum samples prospectively collected from 57/63 consecutive patients transplanted for HCV-related end-stage liver disease were assayed for both serum HCV core antigen by fluorescent enzyme immunoassay and HCV RNA level using a branched chain DNA signal amplification assay. HCV genotype was determined by restriction fragment length polymorphism analysis based on 5' untranslated region. One- and 2-year annual protocol liver biopsies from these patients were graded for inflammation, fibrosis, and cholestasis RESULTS: Serum HCV core antigen and HCV RNA were detected in a similar proportion of samples (256/ 281 vs. 260/281, P=NS), and there was an excellent correlation between assays (r2=0.905, P<0.0001) independent of HCV genotype. A conversion equation between HCV core antigen and HCV RNA was constructed to estimate the HCV core antigen to RNA ratio to be around 231 to 1. Mean serum HCV core antigen levels peaked initially at 3 months posttransplant but there was significant interpatient variation as to when peak levels occurred. A high serum HCV core antigen level in the first 6 months was associated with histological deterioration in terms of bridging fibrosis, cirrhosis, severe cholestasis, or retransplantation by 2-year follow-up. CONCLUSION: Determination of serum HCV core antigen level reflects HCV viremia and may have clinical implications in liver transplant patients with HCV recurrence.