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W K Roth

Publications and source records attributed to W K Roth.

At least 55 records · Page 3Linked to original sources
PubMed1997

Non-isotopic detection of hepatitis C virus quasispecies by single strand conformation polymorphism.

In patients infected with the hepatitis C virus (HCV), a heterogeneous population of viruses, so-called quasispecies exists in vivo. The hypervariable regions (HVR) within the second envelope gene (HCV-E2) show particularly highly intratypic variability and are considered to be the target of neutralizing antibodies. The aims of the study were to optimize a genotype-independent primer set for amplification of HVR-1 and to establish a sensitive SSCP analysis for rapid and non-isotopic detection of predominant serum HCV quasispecies. Using the optimized SSCP technique, changes of quasispecies composition were investigated in five chronically infected patients with HCV before and during interferon-alpha treatment. HCV genotyping was performed by sequence and phylogenetic analysis. In addition, serial viremia and serum alanine aminotransferase (ALT) levels were determined. The SSCP analysis was performed at two time points before and during interferon-alpha therapy, respectively. Four patients showed an alteration of the SSCP pattern during the first three months of interferon-alpha therapy, whereas in one patient the SSCP pattern changed before therapy and remained stable during treatment with interferon-alpha. The present approach for non-isotopic analysis of single strand conformation polymorphism provides a direct, rapid, and sensitive technique for detection of the heterogeneous population of HCV quasispecies of different genotypes. Using this test procedure, investigations of large cohorts of patients with chronic hepatitis C can be undertaken.

Alanine Transaminase↗
PubMed1997

Mutations in the nonstructural 5A gene of European hepatitis C virus isolates and response to interferon alfa.

The response rate to interferon alfa (IFN-alpha) in patients infected with hepatitis C virus (HCV) genotype 1 isolates is poor. A region associated with sensitivity to IFN has been identified in subtype HCV-1b isolates from Japanese patients in the carboxyterminal half of the nonstructural protein NS5A (between codon 2209 and 2248). HCV-1b isolates with at least four amino acid changes in this region compared with the HCV-1b prototype sequence were sensitive, whereas isolates identical to the prototype sequence were resistant to IFN-alpha. Patients infected with HCV-1b isolates carrying 1 to 3 mutations in NS5A(2209-2248) showed an intermediate response pattern. Because of the large geographical differences observed for HCV it is unknown whether this putative IFN-alpha sensitivity determining region is also predictive for European isolates. We analyzed 32 patients chronically infected with HCV-1a or HCV-1b isolates who were treated with 3 million units of recombinant IFN-alpha three times per week for 1 year. Before initiation, during, and after treatment serum HCV-RNA levels were assessed by a quantitative reverse-transcription polymerase chain reaction (RT-PCR) assay. The amino acid sequence of NS5A(2209-2248)was determined by direct sequencing of the PCR-amplified HCV genome and was compared with the reference sequence HCV-J. In patients chronically infected with subtype HCV-1a or HCV-1b the initial or sustained response to IFN-alpha was not related to the number of amino acid substitutions in the NS5A(2209-2248) region. In addition, the number of amino acid changes in NS5A(2209-2248) was not related to pretreatment HCV-RNA serum levels. In three patients with a pronounced initial decline of HCV-RNA levels (>3 log) sequence analyses of NS5A(2209-2248) were performed before and after therapy. Compared with the pretreatment amino acid sequence the HCV isolates of these patients revealed more mutations in the NS5A(2209-2248) region after therapy. These findings from European patients indicate that the NS5A(2209-2248) region of HCV does not represent a common interferon sensitivity determining region.

Adult↗
PubMed1997

Enlargement of perihepatic lymph nodes in relation to liver histology and viremia in patients with chronic hepatitis C.

Inflammatory processes in organs frequently lead to hyperplasia of regional lymph nodes. In the present study, we investigated whether lymph node enlargement within the hepatoduodenal ligament may reflect the inflammatory activity within the liver of patients chronically infected with the hepatitis C virus (HCV). In 114 patients with chronic hepatitis C and 49 healthy controls, the total lymph node volume within the hepatoduodenal ligament was prospectively investigated by ultrasound. In patients with chronic hepatitis C, a liver biopsy was taken at the same occasion, and specimens were semiquantitatively evaluated by the histological activity index (HAI). Hepatitis C viremia was assessed by quantitative reverse transcription-polymerase chain reaction (RT-PCR). Genotyping was performed by a reverse hybridization assay. In 104 of 114 patients (91.2%) and in 45 of 49 healthy controls (91.8%), adequate visualization of the region of the hepatoduodenal ligament was achieved by ultrasound. Lymph nodes were detected in all patients with chronic hepatitis C and in 33 of 45 controls. The mean perihepatic lymph node volume in healthy controls (2.2 +/- 1.8 mL) was lower than in HCV-infected patients with mild to moderate inflammatory activity, severe inflammatory activity, and patients with cirrhosis (5.8 +/- 2.2 mL, 18.1 +/- 10.4 mL, and 22.8 +/- 18.8 mL, respectively). In patients with HCV-RNA levels of less than 10(6) copies/mL, the total lymph node volume was 5.8 +/- 1.6 mL and was significantly increased in patients with higher viremia (20.3 +/- 13.8 mL; P < 10(-6)). No correlation was found between the total lymph node volume within the hepatoduodenal ligament, HCV genotypes, and liver function test results. In conclusion, enlargement of perihepatic lymph nodes in patients with chronic hepatitis C is predictive for the presence of severe inflammatory activity. The mechanism of portal lymphadenopathy in patients with chronic hepatitis is unknown but appears to be related to viral replication within the liver and the immune-mediated inflammatory response of the host.

Adult↗
PubMed1997

Evaluation and comparison of different hepatitis C virus genotyping and serotyping assays.

BACKGROUND/AIMS: Evidence that the geno/subtype of hepatitis C virus (HCV) is predictive of the response to interferon-alpha therapy suggests that typing methods are clinically useful. In the present study, HCV isolates obtained from 74 patients with chronic hepatitis C were used to evaluate three genotyping and two serotyping assays. METHODS: The reverse hybridization assay and the DNA immunoassay are based on immobilized type-specific probes for the 5'-noncoding and the core region, respectively. A third genotyping assay utilized type-specific primers for amplification of the core region. Serotyping assays detect type-specific antibodies of the nonstructural-4 region (enzyme immunoassay) or of the core and nonstructural-4 region (recombinant immunoblot assay). Gold standard geno/subtyping of HCV isolates was performed by sequence and phylogenetic analysis of the nonstructural-5B region. RESULTS: All genotyping systems amplified the respective target region of the HCV genome with high sensitivity. The reverse hybridization assay and the DNA immunoassay correctly identified HCV-1, -2, and -3. The DNA immunoassay misinterpreted all HCV-4 isolates as HCV-4 and -5 coinfection. In the type-specific amplification assay, coinfections of subtypes HCV-1a and HCV-3a with HCV-1b could not be excluded. The reverse hybridization assay misinterpreted 1/14 HCV-1a isolates as HCV-1h, and vice versa 3/36 HCV-1b isolates as HCV-1a. Furthermore, differentiation between HCV-2a and -2c was not possible using this assay. The DNA immunoassay correctly identified all HCV subtypes. The serotyping assays, recombinant immunoblot assay and enzyme immunoassay identified HCV-1, -2, and -3 in 93% and 89% of cases, respectively. HCV-4, however, could only be recognized by the enzyme immunoassay. CONCLUSIONS: The reverse hybridization assay and the DNA immunoassay specifically identified HCV genotypes 1, 2, and 3, while crossreactivity occurred in the primer-specific amplification assay. The DNA immunoassay achieved the best performance in HCV subtyping. Both serotyping systems correctly identified HCV-1, -2, and -3 in about 90% of cases, but lack the possibility of subtyping.

DNA, Viral↗
PubMed1997

Prevalence and clinical and histological manifestation of hepatitis G/GBV-C infections in patients with elevated aminotransferases of unknown etiology.

BACKGROUND/AIMS: Hepatitis G virus (HGV) and hepatitis GB virus-C (GBV-C) are recently identified non-A-E hepatitis-associated viruses. The prevalence of HGV/GBV-C in the general population is high (1.0-1.7%), but data on the clinical and histological manifestations of the new viruses are sparse. In the present study we investigated the prevalence and clinical and histological manifestation of HGV/GBV-C infections in patients with elevated aminotransferase levels of unknown etiology. METHODS: In 52 of 630 consecutive patients referred for evaluation of elevated aminotransferases the underlying liver disease remained unknown. Serum samples of these 52 patients with elevated aminotransferase levels of unknown etiology were tested for HGV/GBV-C RNA by reverse transcription-polymerase chain reaction (RT-PCR) using primers deduced from nonstructural regions. Cloned PCR products were sequenced and compared by phylogenetic analysis. RESULTS: HGV/GBV-C RNA was consistently detected in 7 of the 52 patients (13%). Sequence and phylogenetic analysis revealed the presence of only one subtype, with nucleotide sequence homologies between 86 and 91%. All seven patients had persistent viremia for at least 9 months. In six patients liver function test results normalized, and alanine aminotransferase levels remained persistently elevated in only one patient. Four HGV/GBV-C positive and ten HGV/GBV-C negative patients consented to a liver biopsy, which revealed similar results with minimal to mild chronic hepatitis and mild portal fibrosis. CONCLUSIONS: The prevalence of HGV/GBV-C infections in patients with elevated aminotransferases of unknown etiology is low. Since clinical, biochemical and histomorphologic features of patients with elevated aminotransferases of unknown etiology with and without HGV/GBV-C infection are indistinguishable, the role of HGV/GBV-C in the pathogenesis of chronic liver disease appears insignificant.

Adult↗
PubMed1997

Dynamics of hepatitis B virus infection in vivo.

BACKGROUND/AIMS: Information on the kinetics of the pretreatment steady-state of HBV can be obtained from serial measurements of serum hepatitis B virus (HBV) DNA concentrations following lamivudine ((-)enantiomer of 3'-thiacytidine)-induced perturbation of the balance between virus production and clearance. METHODS: In a placebo-controlled, dose-ranging trial, lamivudine (5 to 600 mg per day) was administered for 4 weeks to 17 patients with chronic replicative hepatitis B. Serum HBV DNA levels were quantified by standard liquid hybridization techniques. The time-dependent concentrations of serum HBV DNA following lamivudine administration were subjected to iterative least-squares regression in order to obtain kinetic data on HBV life-time and viremia. RESULTS: In patients with stable HBe-antigen positive chronic hepatitis B responding to lamivudine, HBV DNA declined exponentially with a half-life of approximately 2-3 days. The minimum virus production and clearance per day in patients with chronic hepatitis B was calculated to be 6.09 x 10(11) virions/day (range 0.26 to 21.06 x 10(11) virions/day). Compared to the HBeAg levels before treatment, relative amounts of HBeAg were 1.00 +/- 0.16 and 0.96 +/- 0.20 at days 22 and 28 of treatment, respectively. Four weeks after termination of lamivudine treatment, the relative amount of HBeAg was 1.04 +/- 0.19. CONCLUSIONS: The half-life of HBV in chronically infected patients is longer and in vivo turnover rates are higher compared to recently published data on the human immunodeficiency virus type 1 and the hepatitis C virus. The constant expression of HBeAg observed in the present study during a 28-day lamivudine treatment period does not allow calculation of a definite decay rate for virus-producing cells. Our data, however, imply that the minimum half-life of infected cells may exceed 100 days.

Adolescent↗
PubMed1997

Prevalence of hepatitis G virus and its strain variant, the GB agent, in blood donations and their transmission to recipients.

BACKGROUND: Hepatitis G virus (HGV) and its strain variant, the GB agent (GBV-C) are independent isolates of a recently identified non-A through -E hepatitis virus. Prevalence in United States volunteer blood donors is 1.5 to 1.9 percent, but no data on European blood donors are available. Epidemiologic data suggest a preferred parenteral transmission route. The prevalence of HGV/GBV-C in European blood donors and the efficiency of transmission to transfusion recipients were investigated. STUDY DESIGN AND METHODS: Plasma samples from unpaid volunteer German blood donors were tested for HGV/GBV-C by in-house reverse transcription-polymerase chain reaction. Positive donors were independently retested and interviewed for parenteral transmission risks. Amplification products were sequenced and subjected to phylogenetic analysis. Recipients of reverse transcription-polymerase chain reaction-positive donations were traced and tested for HGV/GBV-C infection. RESULTS: A total of 14 (1.34%) of 1048 donors (alanine aminotransferase < 45 IU/L) were repeatedly positive for HGV/GBV-C with 9 (2.18%) of 413 urban and 5 (0.78%) of 635 rural donors (chi 2-test; p = 0.04). Isolates differed in nucleotide sequence homology over a range of 12.5 to 19.6 percent. All but one positive donor reported parenteral transmission risks. Transmission of HGV/GBV-C was detected in 4 of 9 transfusion recipients. The prevalence of HGV/GBV-C in donors with an alanine aminotransferase level > 45 IU per L was 3 percent (3/100). Two mother/child pairs were identified with highly homologous isolates. CONCLUSION: A significantly greater prevalence of HGV/GBV-C was detected in urban volunteer blood donors than in rural donors. The high prevalence in urban donors (2.18%) suggests specific transmission risks for this group. The less than 50-percent efficiency of HGV/GBV-C transmission via blood components may indicate the presence of defective viruses with reduced infectivity. There is evidence for vertical transmission.

Adult↗
PubMed1997

Heterosexual transmission of GB virus-C/hepatitis G virus infection.

GB virus-C (GBV-C) and hepatitis G virus (HGV) are recently identified non-A-E hepatitis-associated viruses belonging to the family Flaviviridae. The prevalence of GBV-C/HGV in the general population is high (1.2-3.0%), but data on possible transmission routes are sparse. In this report GBV-C/HGV RNA was detected in a couple by reverse transcription polymerase chain reaction (RT-PCR) using primers deduced from non-structural regions. Neither partner was coinfected with hepatitis B (HBV), hepatitis C (HCV) or human immunodeficiency virus (HIV). The child of the couple tested repeatedly negative for GBV-C/HGV by RT-PCR. The couple had lived in a stable monogamous relationship for 10 years and had never used barrier contraception. Other than sexual risk, factors for transmission were carefully excluded. GBV-C/HGV isolates obtained from the couple were sequenced and phylogenetically analysed together with control GBV-C/HGV isolates. The evolutionary distance between the sequences obtained from the couple (1%) was smaller than between any other GBV-C/HGV sequence. Taken together, the clinical and molecular data provide strong evidence for heterosexual but not vertical transmission of GBV-C/HGV in non-coinfected individuals.

Adult↗
PubMed1997

[Prevalence of hepatitis G virus genome in blood donors].

The relevance of the GB virus C/hepatitis G virus (GBV-C/HGV) in blood banking results from its high prevalence in blood donors and the fact that it is present at a very high percentage (18%) in polytransfused and hemophiliac patients. Since there is no assay available for serological testing, we developed a sensitive PCR utilizing newly designed NS3 primers to investigate the prevalence in blood donors in Hessia. Testing 1,143 accepted blood donors with alaninaminotransferase (ALT) concentrations < 45 U/l we found 15 (1.3%) positive for GBV-C/HGV RNA. From 507 donors settling in urban Frankfurt areas, 10 (2.0%) were positive. Of those donors settling in rural hessian areas only 5/635 (0.8%) tested positive. By testing 100 excluded donors with ALT values > 45 U/l, 3% turned out to be positive. In 4 out of 9 recipients of GBV-C/HGV-positive blood products we detected the donor viral RNA as proved by sequencing and phylogenetic analysis. The virus was transmitted to 3 recipients by erythrocytes and to 1 recipient by platelets. Testing family members of the GBV-C/HGV-positive blood donors we could not detect any intrafamilial transmission.

Blood Banks↗
PubMed1996

Hepatitis C virus sequences encoding truncated core proteins detected in a hepatocellular carcinoma.

RNA was specifically extracted from tumor and peritumor tissue of a hepatitis C virus (HCV)-associated hepatocellular carcinoma after microdissection. RT-PCR products of the HCV 5'-noncoding (NC), core and nonstructural (NS)-5 gene were examined. Nucleotide sequences of the core region derived from the tumor tissue revealed deletions and mutations resulting in truncated proteins. Peritumor and serum HCV sequences were unaffected.

Amino Acid Sequence↗
PubMed1996

Effect of interferon alfa on the dynamics of hepatitis C virus turnover in vivo.

In about 30% to 40% of patients with chronic hepatitis C, treatment with recombinant interferon alfa (r-IFN alpha) causes a decrease of serum aminotransferases and hepatitis C virus (HCV) RNA. The antiviral mechanism of interferon alfa (IFN alpha) in vivo is unknown. From serial measurements of serum HCV-RNA concentrations following IFN alpha induced perturbation of the balance between virus production and clearance, we obtained kinetic information on the pretreatment steady-state of HCV. In patients with chronic hepatitis C responding to IFN alpha, HCV-RNA declined exponentially with a half life of approximately 2 days. Modeling of the data predicts that in patients with chronic hepatitis C responding to IFN alpha this cytokine predominantly acts as an inhibitor of de novo infection of susceptible cells. HCV is released from infected cells with a mean half life of 2.7 +/- 1.3 days, whereas the clearance rate from serum is faster (mean half life, 0.7 +/- 0.4 days). The minimum virus production and clearance per day in patients with chronic hepatitis C was calculated to be 6.7 x 10(10) virions/d (range, 0.2 to 43.8 x 10(10) virions/d). These values showed no correlation with the HCV genotype, aminotransferase levels, or the histological activity as assessed before the administration of r-IFN alpha. Simultaneous kinetic analysis of serum aminotransferases as surrogate markers of hepatocyte integrity revealed half lifes for the release of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) from hepatocytes of 4.7 +/- 3.8 and 3.0 +/- 3.5 days, respectively. The half life data for HCV in chronically infected patients are remarkably similar to recently published data on human immunodeficiency virus type 1 (HIV-1) suggesting that both RNA viruses replicate continuously and highly productive in vivo. The turnover rates explain the rapid generation of viral diversity and the opportunity for viral escape phenomena from the host immune surveillance.

Alanine Transaminase↗
PubMed1996

Phylogenetic analysis of hepatitis C virus isolates and their correlation to viremia, liver function tests, and histology.

Nucleotide sequence analysis of hepatitis C virus (HCV) strains showed substantial variability leading to a classification into several genotypes and subtypes. The data correlating HCV genotypes and subtypes with hepatitis C viremia levels, demographic characteristics of patients (age, mode of transmission, duration of infection), and severity of liver disease are conflicting. The interpretation of several studies is further complicated because the molecular methods used lacked specificity for genotyping/subtyping and underestimated viremia levels, especially in patients infected with HCV genotypes 2 and 3. In the present study we investigated 97 consecutive patients with chronic hepatitis C using molecular "gold standard" methods. HCV subtyping was performed by sequence and phylogenetic analysis of the nonstructural (NS)-5 region and serum HCV-RNA concentration was assessed by a validated genotype-independent quantitative reverse-transcription-polymerase chain reaction assay using an internal RNA standard. Patients infected with subtypes HCV-1b, HCV-2a-c, and HCV-4 were older than patients infected with HCV-1a and HCV-3a. Serum HCV-RNA levels ranged from 1.5 x 10(4) to 1.0 x 10(8) copies/mL with no significant differences between median serum HCV-RNA concentrations in patients infected with different genotypes/subtypes. Although patients infected with HCV-1b were older, no biochemical or histological evidence was obtained that this subtype is associated with more severe liver disease. Furthermore, the present study showed a lack of correlation between the serum HCV-RNA concentration, biochemical parameters, and liver histology. The median serum HCV-RNA levels in patients with chronic persistent hepatitis, chronic active hepatitis, and liver cirrhosis were 5.0 x 10(6) copies/mL, 2.5 x 10(6) copies/mL, and 5.0 x 10(6) copies/mL, respectively. These differences were not significant. In conclusion, using optimized and validated molecular techniques, the present cross-sectional study showed no correlation between HCV genotypes/subtypes, viremia, liver function test results, and histology.

Adult↗
PubMed1996

Phylogenetic analysis of hepatitis C virus isolates from hemodialysis patients.

A high prevalence of hepatitis C virus (HCV) infection has been reported in hemodialysis patients. Main risk factors for transmission are previous blood transfusions and possibly nosocomial infections within the dialytic environment. In the present study 224 hemodialysis patients from the same department were tested for the presence of anti-HCV antibodies and HCV-RNA. The presence of anti-HCV in hemodialysis patients was correlated with a history of more than 10 blood transfusions (P = 0.001) and with a duration of hemodialysis treatment for more than 10 years (P = 0.001). The issue of possible patient-to-patient infection was addressed by sequence analysis of all HCV-RNA positive hemodialysis patients (N = 14) together with a control panel of HCV isolates from 56 unrelated non-hemodialysis patients with hepatitis C from the same geographical area. Subsequent phylogenetic analysis of nucleotide sequences obtained from the 5'-noncoding region and the nonstructural NS-5 region of the HCV genome revealed that only two hemodialysis patients were infected by a highly related HCV isolate. The remaining HCV-RNA positive hemodialysis patients including those without previous blood transfusions were all infected by phylogenetically-distant HCV isolates, providing evidence against a nosocomial transmission route. The data of the present study show that molecular epidemiological techniques are important to investigate the issue of nosocomial infection. In our hemodialysis unit patient-to-patient infection appears uncommon and draws attention towards other possible (such as, blood products such as human serum albumin, immunoglobulins) or even yet unrecognized transmission routes.

Adult↗
PubMed1996

p53 autoantibodies in patients with pancreatitis and pancreatic carcinoma.

In human pancreatic carcinoma (PCa) mutations in the p53 tumor suppressor gene are present in up to 50% of cases. Conformational change and cellular accumulation, together with subsequent release of mutant and normal p53 protein from transformed cells, may initiate a B-cell response with generation of circulating autoantibodies to p53 protein (anti-p53). In the present study we analyzed the sera of 85 consecutive patients with acute pancreatitis (N = 19), chronic pancreatitis (N = 33), and PCa (N = 33) to evaluate the specificity of autoantibodies to p53 protein as a serological marker for PCa. Detection of anti-p53 was performed using an enzyme-linked immunosorbent assay system with immobilized recombinant wild-type p53 protein. Autoantibodies to p53 were detectable in 1 of 19 patients with acute (5.3%) and in 4 of 33 patients with chronic pancreatitis (12.1%). All anti-p53-positive patients with acute or chronic pancreatitis were carefully examined and no underlying malignant disease was found. During follow-up (range, 281-647 days; mean, 472 days) none of these patients showed any evidence for subsequent development of PCa or any other malignant disease. In patients with PCa, anti-p53 was detected in 6 of 33 cases, resulting in a sensitivity of 18.2% with a specificity of 90.4%. In contrast to anti-p53, detection of serum carbohydrate antigen (CA 19-9) resulted in a sensitivity and specificity of 69.7 and 71.2% (CA 19-9, > 37 U/ml) and 51.5 and 96.2% (CA 19.9, > 100 U/ml) for the detection of PCa, respectively. Taken together, the sensitivity of anti-p53 formation was low in patients with PCa (18.2%). Furthermore, the detection of anti-p53 was not specific for malignancy, indicating that severe inflammatory processes may also induce anti-p53 formation.

Acute Disease↗
PubMed1996

Comparison of two quantitative hepatitis C virus reverse transcriptase PCR assays.

A quantitative hepatitis C virus reverse transcriptase PCR (HCV RT-PCR) assay established in our laboratory was compared with the Roche Amplicor HCV Monitor test kit for agreement of test results and intra-assay variability. Both assays rely on reverse transcription and amplification of extracted RNA from patients' sera together with an internal RNA standard derived from the 5'-noncoding region of HCV. A panel of clinical serum samples (n = 33) was quantitatively analyzed in parallel by both test systems. The methods demonstrated substantial agreement between 1 x 10(3) and 5 x 10(5) HCV RNA molecules per ml of serum. However, with sera containing more than 5 x 10(5) copies per ml, according to our in-house assay, the results diverged on average in a nonacceptable range of 2 orders of magnitude. Our in-house HCV RT-PCR assay measured up to 5 x 10(7) HCV-RNA molecules per ml in some serum samples. However, the Roche Amplicor HCV Monitor test kit did not detect more than 2 x 10(6) molecules in any of the serum samples tested. After dilution of serum samples prior to testing, an approximately 0.5 order of magnitude more HCV RNA molecules was detected by the Roche HCV test kit in sera containing high copy numbers (> 5 x 10(5) RNA copies according to the in-house assay). The in-house PCR and the Roche Amplicor HCV Monitor test kit revealed coefficients of variation of 6.2 and 7.5%, respectively.

Base Sequence↗
PubMed1996

Risk factors for the transmission of hepatitis C.

BACKGROUND: Due to the availability of testing for antibodies to the hepatitis C virus (anti-HCV) and with the use of the polymerase chain reaction (RT-PCR) to detect HCV-RNA, more sensitive and specific measures can be applied to assess routes of HCV transmission. The aim of the present study was to investigate possible risk factors for transmission of HCV. METHODS: 160 consecutive patients with chronic hepatitis C (mean age 47.1 +/- 14.1 yr) attending a hepatology out-patient clinic were interviewed to identify transmission risk factors. Genotyping of HCV isolates was performed by direct sequencing of RT-PCR products in the 5'-noncoding and the NS-5 region. RESULTS: The risk factors of HCV infection were as follows: transfusion of blood or blood products 34.4%, intravenous drug abuse 20.6%, heterosexual contact 3.8%, occupational risk 1.9% and tattoo 0.6%. In 62/160 (38.7%) the route of transmission remained unknown. In one HCV-infected couple we analyzed the nucleotide sequences of the NS-5 region of the respective HCV isolates and found almost complete sequence homology (> 97%). The majority of patients with post-transfusional or unknown mode of transmission were infected with genotype HCV-1a and -1b, while in 6/10 patients with previous i.v. drug abuse, genotype HCV-3a was present. We found no evidence that the mode of disease acquisition influences the course of liver disease. CONCLUSION: The majority of patients with chronic hepatitis C have a classical parenteral transmission risk factor. In our study, no source of HCV acquisition was identified in 38.7% of patients. It may well be that the major factors in these "sporadic" HCV infections are variations on the known risk factors. However, since the proportion of these cases is rather high, further attention should be on alternative and as yet unclear transmission routes.

Adolescent↗
PubMed1995

Alpha-fetoprotein and p53 autoantibodies in patients with chronic hepatitis C.

Hepatitis C virus infection is a common cause of chronic liver disease and hepatocellular carcinoma. Recently, mutations in the p53 tumor suppressor gene with generation of circulating autoantibodies to p53 protein have been detected in a significant proportion of patients with different malignancies. Using ELISA methods we assessed alpha-fetoprotein and anti-p53 as serological screening parameters for hepatocellular carcinoma in 147 consecutive patients with chronic hepatitis C. Liver cirrhosis was histologically diagnosed in 58 patients (39.5%) and a hepatocellular carcinoma confirmed in seven patients (4.8%). Serum alpha-fetoprotein was raised above 20 ng/ml in 26/147 patients and above 100 ng/ml in 5/147 patients. In 6/7 patients with hepatocellular carcinoma, alpha-fetoprotein was raised above 20 ng/ml, but only in 3/7 cases above 100 ng/ml, resulting in a sensitivity and specificity of 85.7% and 85.7% (alpha-fetoprotein > 20 ng/ml) and 42.9% and 98.6% (alpha-fetoprotein > 100 ng/ml) for the detection of hepatocellular carcinoma, respectively. Autoantibodies to p53 were detected in 3/7 patients with hepatocellular carcinoma, but in 0/140 patients without malignancy (sensitivity 42.9%, specificity 100%). Screening for hepatocellular carcinoma was improved by combining alpha-fetoprotein measurement (level > 100 ng/ml) with detection for anti-p53 (sensitivity 71.4%, specificity 98.6%). In conclusion, the presence of anti-p53 was highly specific for malignancy and independent of alpha-fetoprotein status. Further studies including a larger number of patients with hepatitis C virus-related hepatocellular carcinoma are required to investigate whether serological testing for anti-p53 in combination with alpha-fetoprotein might improve the detection of hepatocellular carcinoma in high-risk patients with liver cirrhosis.

Autoantibodies↗