Hepatitis C virus genotypes in chronic hepatitis C of children

Several hepatitis C virus (HCV) genotypes have been recently identified and genotype 1b has been correlated with severe liver disease and a poor response to interferon therapy. HCV infection in children is an interesting model for evaluation of the relationship between HCV genotypes and liver disease, because of its relatively short duration and the infrequent association with confounding cofactors. We have investigated HCV genotypes, using a dot-blot hybridization assay with genotype-specific probes, in 36 Italian children with chronic hepatitis C who were otherwise well and had no other underlying disease. Only four patients were symptomatic; liver histology, obtained in 33 patients, showed minimal hepatitis in 17 and mild chronic hepatitis in 16. Infection with HCV genotype 1b was found in 55.5% of patients, with a peak prevalence of 83% in children from southern Italy (P < 0.05 vs other regions). The remaining children were infected with HCV genotype 1a (16.6%), genotype 2 (11.1%), and mixed (10.9%) or undetermined (2.7%) genotypes. In one patient, HCV viraemia was never detected. There was no statistically significant correlation between genotype and age, sex, source of infection, alanine aminotransferase pattern and histological activity index. These results indicate that genotype 1 b is widespread among Italian children with chronic hepatitis C, although with significant geographical variations. It is not associated with a more severe liver disease, therefore suggesting that the greater severity of liver disease recently reported in adults could reflect the cumulative effects of disease duration and of interfering cofactors.

Heterogeneity of hepatitis C virus

A great deal of information on the molecular heterogeneity of hepatitis C virus (HCV) has been achieved since its discovery in 1989. However, little is known about the clinical significance of these variations. Based on the degree of sequence variation, HCV has been classified into six major groups or types, differing by 31-34% at the nucleotide level over the entire virus genome. Each type is divided into several subtypes that differ by 20-23% in nucleotide sequence. Viruses within the same subtype are up to 10% divergent and, within infected individuals, vary by up to 1.5%. Genotype distributions are not homogeneous around the world and may reflect both historical and recent parenteral routes of transmission. The clinical implication of these genomic variations are not yet fully elucidated: genotype 1b has been associated with end-stage liver disease, including liver cirrhosis and hepatocellular carcinoma, but this finding might rather reflect its earlier introduction to the populations studied. Consistent evidence exists that types 2 and 3 have a higher response rate to interferon treatment than type 1, although the interplay between genotype and viral load in determining the response is still unclear. Immunohistochemical studies indicate a stronger activation of the endogenous interferon system in the liver of patients infected with type 1 compared to those infected with types 2 and 3, explaining, at least in part, its low responsiveness to exogenous interferon treatment. Biological, sequence-dependent variations of genotypes have been poorly investigated to date, but differential efficiency of translation activity of the 5' non-coding region has been reported. The availability of "in vitro" systems for evaluating pathogenetic aspects and neutralization mechanisms will improve the present knowledge on this world-wide infectious disease and on the clinical usefulness of distinguishing between genotypes.

Persistent hepatitis C viremia predicts late relapse after sustained response to interferon-alpha in chronic hepatitis C. TriVeneto Viral Hepatitis Group

OBJECTIVE

To define long-term outcome in patients with chronic hepatitis C who remain viremic after sustained biochemical response to interferon-alpha therapy.

DESIGN

Prospective evaluation of an outpatient cohort.

SETTING

University hospital.

PATIENTS

107 patients with chronic hepatitis C who maintained normal aminotransferase levels as long as 12 months after interferon-alpha therapy. Patients were followed prospectively for an additional 6 to 36 months.

MEASUREMENTS

Aminotransferase levels were monitored at 3-month intervals. Serum hepatitis C virus (HCV) RNA was tested by polymerase chain reaction before therapy, at the end of therapy, and 12 months after therapy. The HCV genotype was defined by spot hybridization using serum specimens obtained before treatment.

RESULTS

Hepatitis C virus RNA was detected in 27 (25%) patients with sustained biochemical response; 80 (75%) patients were negative for HCV RNA. Patients positive for HCV RNA were older (P < 0.001), had received a smaller interferon-alpha dose (P = 0.02), and were more frequently infected with HCV genotype 2 (P < 0.01). Liver histologic findings were active in 57% of patients positive for HCV RNA, despite normal alanine aminotransferase levels, compared with only 12% of patients who were negative for HCV RNA (P = 0.01). The estimated probability of hepatitis relapse by 4 years after therapy was 53% in viremic patients and 0% in patients negative for HCV RNA (P < 0.001).

CONCLUSION

Patients with chronic hepatitis C should be tested for serum HCV RNA 1 year after a sustained biochemical response to interferon-alpha therapy to determine whether the response is complete and permanent.

Hepatitis C genotypes in patients with dual hepatitis B and C virus infection

In patients with chronic hepatitis B and C virus (HBV, HCV) infection, an inverse relationship in the replicative activity of the two viruses has been reported. In the present study the genotype of HCV was evaluated in 34 consecutive cases found with hepatitis B surface antigen (HBsAg) and anti-HCV in the serum, in order to identify its possible influence in determining the pattern of HBV/HCV interaction. Nineteen patients were HCV-RNA positive and could be genotyped: 8 were infected by HCV-1 (3 by HCV-1a and 5 by HCV-1b), 10 by HCV-2, and only 1 by HCV-3. Among these, 3 were HBV-DNA positive, compared to 10 of 15 HCV-RNA-negative patients (P = 0.003), and all 3 were coinfected with HCV-2. Mean alanine aminotransferase (ALT) levels were similar between patients infected with HCV-1 and HCV-2. Among 7 patients with cirrhosis 5 were infected by HCV-2, while 6 of 12 of those without cirrhosis had HCV-1 infection. In conclusion, HBV replication was inhibited more efficiently by HCV-1 than by HCV-2. Cirrhosis was frequently found in patients with dual HBV and HCV-2 infection.

Clinical evaluation of a single reaction, diagnostic polymerase chain reaction assay for the detection of hepatitis C virus RNA

BACKGROUND/AIMS

In the past few years the detection of HCV-RNA by polymerase chain reaction has become a well-established diagnostic tool for patients with chronic hepatitis C. However, the lack of reproducible results between laboratories and the relatively high proportion of false-positive results, has indicated the need for a standardized and reliable polymerase chain reaction assay. In the present study we have analyzed the performance of a commercial, HCV-RNA polymerase chain reaction assay based on a single, combined reverse transcription and amplification reaction and on the use of Uracil-N-glycosilase to prevent carry-over contamination (Amplicor HCV, Roche Molecular Systems).

METHODS

In this assay the amplification products are detected in microwell plates using biotinylated primer and the HRP avidin colorimetric system. Serum samples collected from 446 patients, including 181 with chronic active hepatitis C, 50 with autoimmune chronic hepatitis, 117 in hemodialysis, 30 asymptomatic carriers of anti-HCV and 68 with indeterminate serology (RIBA indeterminate results), as well as from 121 controls were tested with the commercial, single-step assay and with nested polymerase chain reaction. Both techniques use primers located within the 5' non-coding region of the HCV genome.

RESULTS

In all cases a good concordance was observed between the commercial, single-step assay and nested polymerase chain reaction which, for patients with chronic active hepatitis, showed a sensitivity and specificity of 100% and 99.3% for the former and of 98.8% and 100% for the latter, when compared to clinical diagnosis taken as the gold standard. Most of the 11 discordant samples were seen in the group of RIBA-indeterminate cases and in patients with chronic active hepatitis C. Further analysis of these cases, based on repeat testing and clinical data showed that 64% and 36% of the discrepancies were due, respectively, to nested polymerase chain reaction and Amplicor inconsistent reactions. In hemodialyzed patients, patients with autoimmune hepatitis and asymptomatic carriers of anti-HCV, both assays produced results which were consistent with the clinical diagnosis. In the former group, polymerase chain reaction was able to identify the presence of active viral replication in some antibody negative samples.

CONCLUSIONS

Taken together, these results indicate that the commercial, single-step polymerase chain reaction assay has the same clinical sensitivity and specificity as nested polymerase chain reaction and that, because of its simplified procedures and fast turn-around time, it may be a valuable test for routine diagnostic applications.

Comparison of genotyping and serotyping methods for the identification of hepatitis C virus types

The usefulness of identification of hepatitis C virus (HCV) genotype has recently been investigated for the clinical management of patients infected by HCV. In the present study, the HCV genotype infecting 127 patients was determined by two different methods: HCV genotyping using a dot-blot assay with type-specific probes derived from the 5'-UTR of HCV genome and HCV serotyping using an ELISA system in which type-specific antibodies against the NS4 region were detected. Overall, a good correlation of the two methods was observed, the main discrepancy being 4 patients with sequence-confirmed HCV-2 (2 cases) and HCV-3 (2 cases) genotypes recognized as HCV-1 by serotyping. Mixed infections were not detected by either method. In 19 PCR negative sera, in which the HCV genotype could not be evaluated, no particular serotype profile was observed. In conclusion, the molecular and serological techniques are almost equivalent in determining the viral type, although in individual cases, especially in PCR negative patients, the clinical meaning of the serotyping result remains to be determined.

Hepatitis C virus genotypes and severity of chronic liver disease in haemophiliacs

We studied the activity and stage of chronic liver disease in 45 HCV-seropositive/HIV-seronegative patients with severe haemophilia followed for at least 10 years. HCV-RNA was detected in serum in 36 patients (80%) Viraemic cases were further analysed for HCV genotypes: 10 (28%) were infected by type 1a, 10 (28%) by type 1b, seven (19%) by type 2, four (11%) by type 3, four (11%) had mixed infections (one by 1a + 1b, one by 1a + 2, one by type 2 + 3, and one by 1a + 2 + 3). ALT levels were within the normal range in 55% of the HCV-RNA negative patients but in only 11% of the viraemic cases. Results show a trend for higher levels of ALT in HCV-RNA-positive patients compared with those without viraemia (98 +/- 56 v 60 +/- 61), and particularly with patients with type 3 HCV infection (148 +/- 44). We suggest that a slow progression of chronic liver disease occurs in haemophilic HCV-positive/HIV-negative patients and conclude that presence of HCV-RNA in serum correlates well with cytolitic damage but, in the time-scale of our follow-up period, commonly used clinical-laboratory parameters cannot predict the chronic evolution of liver infection or identify differences in disease progression in relation to specific HCV subtypes.

Randomized trial comparing three different regimens of alpha-2a-interferon in chronic hepatitis C. The TriVeneto Viral Hepatitis Group

Alpha-interferon (IFN-alpha) is an effective treatment for chronic hepatitis C, but only 20% to 30% of patients are apparently cured with the current recommended schedule of 3 MU given three times a week for 6 months. To evaluate the efficacy of more aggressive treatment regimens, we have conducted a randomized trial in 174 patients with chronic hepatitis C using three different schedules: (1) 12-month treatment starting with 6 MU/ three times a week and decreasing the dose on the basis of serum alanine transaminase (ALT) activities (group A: 59 cases); (2) fixed dose of 3 MU three times a week for 12 months (Group B: 61 cases), (3) fixed dose of 6 MU three times of week for 6 months (Group C: 54 cases). Patients were evaluated during therapy for biochemical and virological response and followed for at least 12 months after therapy to assess long-term efficacy and liver histological outcome. The genotype of infecting HCV was also analyzed in all patients, and predictors of response were determined by multivariate analysis. Serum ALT became normal during therapy in 76% of patients (95% confidence interval [CI]: 63 to 86), 65% (CI: 52 to 77), and 74% (CI: 60 to 85) in groups A, B, and C, respectively (P = NS). The corresponding figures for sustained response 12 months after therapy were 49% (CI: 36 to 62), 31% (CI: 20 to 44), and 28% (CI: 16 to 42)(A vs. B, P = .06; A vs. C, P = 0.03). Eighty-six percent of patients with sustained response cleared HCV-RNA from serum, and 72% improved histologically.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus infection and liver failure in patients undergoing allogeneic bone marrow transplantation

The role of hepatitis C virus (HCV) infection in severe liver failure (LF) following bone marrow transplantation is still uncertain. We therefore decided to determine the presence of HCV-RNA in 31 patients who died of severe LF after BMT and in 26 matched BMT controls who did not develop LF. HCV-RNA was identified by polymerase chain reaction and anti-HCV by second generation enzyme-linked immunoassay and by 4-band recombinant immunoblotting assay in serum samples obtained before and after BMT. Biochemical and clinical parameters of liver disease were obtained by reviewing clinical records. LF developed at a median interval of 80 days (20-570) from transplantation and was clinically assessed as VOD (n = 7), liver GVHD (n = 5) or hepatitis (n = 19). HCV-RNA was detected, respectively, in 15/31 (48%) and in 12/26 (46%) of LF patients and controls (P = 0.9). Conversely, the risk of dying of LF was 62% and 53% (P = 0.5) respectively, for HCV-RNA positive and negative patients. Anti-HCV profile did not correlate with viremia, nor with type of liver disease. These findings indicate that, despite a 47% prevalence of HCV infection in our series, HCV-RNA positivity was neither a predictor of VOD nor a marker for life-threatening liver disease.

Serologic and molecular evidence for a possible pathogenetic role of viral infection in CD3-negative natural killer-type lymphoproliferative disease of granular lymphocytes

We studied a series of 18 patients with CD3- lymphoproliferative disease of granular lymphocytes (LDGL) for evidence of chronic viral infection, including Epstein-Barr (EBV), hepatitis B (HBV), hepatitis C (HCV), human T lymphotropic virus (HTLV), and human immunodeficiency virus (HIV). Although all patients tested had serologic evidence for past infection with EBV, polymerase chain reaction (PCR) analysis of peripheral blood mononuclear cell (PBMC) DNA utilizing specific EBV primers demonstrated the presence of EBV-DNA in only six of 17 CD3- LDGL cases. A previous history of HBV infection, as defined by the presence of circulating IgG anti-HBc antibodies associated with either HBsAg positivity or negativity, was documented in seven cases; however, viral DNA was not detected in PBMC of these patients using PCR with specific HBV primers. Specific anti-HCV antibodies, confirmed by recombinant immunoblot assay, were detected in five CD3- LDGL patients; PCR analysis demonstrated the presence of viral RNA in PBMC of two of these cases. No patient had antibodies to HTLV-I/II or HIV-1/2. Five patients were infected by more than one virus (two with HBV and EBV and three with HBV and HCV). Our results provide serologic evidence for past viral infection in the large majority of CD3- NK-type LDGL patients. These data suggest that viral infection may have played a role early in disease pathogenesis and may no longer be necessary in sustaining GL proliferation in CD3- NK-type LDGL.

Hepatitis C virus (HCV) genotype, tissue HCV antigens, hepatocellular expression of HLA-A,B,C, and intercellular adhesion-1 molecules. Clues to pathogenesis of hepatocellular damage and response to interferon treatment in patients with chronic hepatitis C

To obtain information on the mechanisms of hepatocellular damage and the determinants of response to interferon, hepatitis C virus (HCV) genotype, tissue HCV antigens, hepatocellular expression of HLA-A,B,C and intercellular adhesion-1 molecules, and the number of lobular T lymphocytes were studied in 38 anti-HCV-positive patients. 14 patients did not show a primary response to interferon treatment. HCV genotype 1b was detected in 11 of them. They displayed higher scores of HCV-positive hepatocytes, HLA-A,B,C, and ICAM-1 molecules expression than with the responders. HCV-infected hepatocytes maintained the capacity to express HLA-A,B,C and ICAM-1 molecules. CD8-positive T cells in contact with infected hepatocytes and Councilman-like bodies were observed. A significant correlation was found between the number of lobular CD8-positive T cells and alanine amino transferase levels. No differences were observed in clinical, biochemical, and histological features between patients with high and low number of hepatocytes containing HCV antigens. These data suggest a prominent role of T cell-mediated cytotoxicity in the genesis of hepatocellular damage. The high expression of interferon-inducible antigens like HLA-A,B,C molecules suggests the presence of strong activation of the interferon system possibly related to high HCV replication in nonresponder patients infected with genotype 1b.

Predictors of sustained response, relapse and no response in patients with chronic hepatitis C treated with interferon-alpha

Three main patterns of response are seen when interferon-alpha (IFN-alpha) is used for the treatment of chronic hepatitis C: 1 sustained response with alanine-aminotransferase (ALT) normalization that is maintained after cessation of therapy, with or without clearance of serum hepatitis C virus (HCV) RNA; 2 transient response with ALT normalization during therapy followed by relapse after its withdrawal, and 3 no response with no or only partial reduction in ALT levels. In order to define variables that could predict each of these three types of response we studied 321 cases of chronic hepatitis C treated with IFN-alpha in two consecutive trials conducted in our Unit. By univariate analysis, age < 45 years (P < 0.01), known disease duration < 60 months (P < 0.01), normal gamma-glutamyl-transpeptidase (gamma GT) levels (P < 0.01) and infection by HCV genotype 2 or HCV genotype 3 (P < 0.01) were found to be statistically associated with sustained response while age > 45 years (P < 0.01), body weight (P = 0.05), cirrhosis (P < 0.01) and elevated gamma GT levels (P < 0.01) were associated with no response. By multivariate analysis sustained response was predicted by HCV genotype 2 (P < 0.01) and HCV genotype 3 (P < 0.01), known disease duration (P < 0.01), patient's age (P < 0.05) and associated with the use of a more aggressive treatment schedule (P < 0.05). Transient response with relapse was predicted by known duration of disease (P < 0.05), HCV genotype 1 (P < 0.05) and female sex (P < 0.05). No response was statistically associated with elevated gamma GT levels (P < 0.01), higher body weight (P < 0.05) and with the less aggressive regimen of 3 MU of natural IFN-alpha given three times weekly for 6 months (P < 0.05). These results indicate that the HCV genotype as well as the schedule of treatment greatly affect the pattern of response to IFN in chronic hepatitis C and allow us to define criteria to predict which type of response is more likely in individual patients.

HCV-associated liver cancer without cirrhosis

Chronic infection with hepatitis C virus (HCV) is regarded as a risk factor for hepatocellular cancer, mostly in patients with liver cirrhosis. We looked for HCV genomes in the livers of patients with hepatocellular cancer who did not have cirrhosis to see whether HCV was directly oncogenic. Cancerous and non-cancerous liver tissue, and serum samples from 19 patients negative for hepatitis B surface antigen were analysed by polymerase chain reaction for the presence of HCV genome, HCV replication, HCV genotyping, and HBV genome. 13 of 19 patients were HCV RNA-positive in cancerous and non-cancerous liver tissue; 8 of 17 tested were anti-HCV positive. Among the 13 HCV RNA-positive patients, 11 had genotype 1b and 2 had genotype 2a. 7 of 13 serum samples were HCV RNA positive. 7 of 19 patients were HBV DNA positive in cancerous and non-cancerous liver tissue, 5 of them anti-HBc positive. 4 patients were both HCV RNA and HBV DNA positive and 3 were both HCV RNA and HBV DNA negative. Our results provide evidence for the association of HCV, mostly genotype 1b, with hepatocellular cancer without the intermediate step of cirrhosis.

The effect of interferon alfa and ribavirin combination therapy in naive patients with chronic hepatitis C

BACKGROUND

Chronic hepatitis C may lead to cirrhosis and hepatocellular carcinoma in a subset of patients. Because response rates with interferon alfa therapy are unsatisfactory, new therapies are needed.

METHODS

We conducted a three-arm, randomized trial in 45 interferon-naive men (mean age 40.6 +/- 12 years) with chronic hepatitis C to compare treatments: group A, ribavirin alone (15 mg/kg daily for 6 months); group B, interferon alone (3 MU thrice weekly for 6 months); and group C, interferon plus ribavirin at the above doses. Histologic outcomes of therapy were assessed by pretreatment and post-treatment liver biopsies.

RESULTS

In group A, alanine aminotransferase levels normalized during therapy in 66% of those with HCV-1b and 34% of those with HCV-2a, but all patients relapsed after treatment ended. In group B, alanine aminotransferase levels normalized during treatment in 66%, 75%, and 100% of patients infected with HCV-1b, HCV-2a, and HCV-3, respectively; however, a sustained response was noted in only 25% of those with HCV-3. In group C, a sustained normalization of alanine aminotransferase with negative serum HCV RNA was seen in 20% of those with HCV-1b, 40% of those with HCV-2a, and 75% of those with HCV-3 12 months after therapy. One year after therapy ended, group C demonstrated a significant sustained response (47%) as well as a significant reduction in piecemeal necrosis and portal inflammation (p < 0.05).

CONCLUSIONS

Combination therapy was significantly superior to ribavirin or interferon monotherapy in producing a sustained response in interferon-naive patients with chronic hepatitis C (p < 0.05). The results of our study suggest that ribavirin potentiates the effect of interferon therapy in chronic hepatitis C.

Distribution of three major hepatitis C virus genotypes in Italy. A multicentre study of 495 patients with chronic hepatitis C

Different genotypes of hepatitis C virus (HCV) have been shown to have distinct geographical distribution and to associate with variable clinical features. To evaluate their role in chronic hepatitis in Italian patients, we studied 495 consecutive cases with chronic hepatitis C seen in nine sentinel centres homogeneously distributed over Italy. HCV genotyping was carried out using a dot-blot hybridization assay with genotype-specific probes. Four hundred and eleven patients were viraemic and could be evaluated: 57% were found to be infected with HCV-1, 31% with HCV-2, 8% with HCV-3, 1% showed mixed infection and 3% were ascribed to HCV-2b or HCV-4 by direct sequencing. Geographical distribution showed discrete territorial variations. A history of drug addiction was commoner in patients infected with HCV-3. There were no significant differences in activity of liver disease among different HCV genotypes but the response to interferon therapy was reduced in patients infected with HCV-1 compared to HCV-2 or HCV-3.

The interaction between hepatitis B virus and hepatitis C virus in acute and chronic liver disease

Infections by the hepatitis B or C virus are extremely common causes of acute and chronic liver disease, and coexistence of the two viruses in the same patient is not rare. Evidence has been found that such interaction may play an important role in fulminant hepatitis and in the development of hepatocellular carcinoma in cirrhotic patients. Liver disease activity and prognosis have been reported to be generally more serious in the presence of double infection, although an inverse relationship in the replicative levels of the two agents has been noted, suggesting viral interference, particularly in cases of chronic hepatitis. Thus, the two viruses seem to inhibit each other at the molecular level, while cytopathic effects appear to be enhanced. Further studies are needed to explain the mechanisms of these apparently contrasting effects.

Serum markers of hepatic fibrogenesis in chronic hepatitis type C treated with alfa-2A interferon

Hepatic fibrogenesis is a dynamic process which characterizes the course of chronic hepatitis. It has stimulated interest in the possible effect of interferon therapy on liver fibrosis. We have evaluated a panel of serum markers of fibrogenesis, namely N-terminal procollagen III peptide (PII-INP), C-terminal procollagen I peptide (PICP), laminin and hyaluronate in 35 patients with chronic hepatitis type C, before, during and after interferon treatment. Before treatment, PIIINP was elevated in 8.5%, 44% and 71% of patients with chronic persistent hepatitis, chronic active hepatitis and cirrhosis, respectively, while the corresponding figures for PICP were 0%, 50% and 46%, and for laminin 16.5%, 70% and 71%; hyaluronate was elevated in only five out of seven patients with cirrhosis. Patients with high PIIINP levels at presentation and a persistent response to treatment showed persistent normalization of this parameter, which was not observed in non-responders. In contrast, the other markers showed no significant correlation with interferon response. These results indicate that PIIINP correlates with interferon response in chronic hepatitis type C.

A randomized controlled trial of thymopentin therapy in patients with chronic hepatitis B

Strategies of treatment of chronic hepatitis type B are currently based on the use of either antiviral or immunomodulatory agents. A randomized, controlled trial was performed to assess the safety and efficacy of 6-month thymopentin therapy in 30 patients with chronic hepatitis B. Inclusion criteria were biopsy-proven chronic hepatitis, elevated alanine aminotransferase and serum HBsAg and HBV-DNA positivity for at least 12 months. At the conclusion of the study (1 year), HBV-DNA was negative and alanine aminotransferase had normalized in 13% and 20% of treated cases and in 20% and 27% of controls. None of the ten treated and one of the nine control patients who were initially HBeAg positive subsequently cleared HBeAg. None became HBsAg negative. A histologic improvement was noted in 27% of the treated patients compared with 18% of controls. These results indicate that this regimen of thymopentin therapy is not effective in treating chronic hepatitis B.

Analysis of the hepatitis C virus genome in patients with anti-LKM-1 autoantibodies

Hepatitis C virus genotypes have been characterized in 22 patients with anti-LKM-1 positive chronic hepatitis C. Following the Simmonds classification, 77% of patients were infected by hepatitis C virus genotype 1, 18% by genotype 2 and 5% by genotype 3, thus excluding the association of the autoimmune reaction with a particular viral type. Prevalences of genotype 1 and 2 were significantly different from those obtained in 79 patients with chronic hepatitis C who were negative for anti-LKM-1, as these were more rarely infected by genotype 1 and more frequently by genotype 2. Clinical findings of anti-LKM-1 positive patients were similar in all three groups. Sequence analysis of the amplified 5'UTR provided identification of peculiar and identical nucleotide substitutions in two out of four patients with genotype 2. The analysis of the secondary structure of this region showed that the observed nucleotide mutations increased the stability of the stem formed in this position.

Evidence against the role of hepatitis C virus in severe liver damage occurring early in the course of acute leukemia in children

Severe liver damage revealed by a sharp transaminase elevation may be seen in patients with leukemia. This may be due to several possible causes, including viral hepatitis, chemotherapy-induced hepatotoxicity and leukemic infiltration. HCV infection may be suspected to play a relevant role as these patients are often heavily transfused after the onset of their hematologic disorder. We have therefore examined the role of HCV in 15 children with leukemia who developed severe liver damage shortly after the diagnosis of leukemia. All patients were tested for HCV-RNA by the polymerase chain reaction at the time of peak SGPT elevation and for anti-HCV on serial serum samples taken thereafter. Only one patient (6.6%) showed hepatitis C viremia and none developed confirmed anti-HCV positivity during follow-up, suggesting that HCV had not played a major role in causing these severe episodes of liver necrosis. This is in agreement with observations made in non-immunocompromised patients in whom fulminant hepatitis is only exceptionally due to HCV.

Cytokeratins patterns in childhood primary liver tumors

Expression of cytokeratins no. 7 and no. 19, typical of the mature biliary tract and of embryonic and fetal hepatocytes, has been evaluated in primary liver tumors from 12 children. Of 7 children with hepatoblastoma, 6 were strongly reactive for cytokeratin no. 19 and only 4 were weakly positive for cytokeratin no. 7. In contrast, the remaining tumors, including 2 hepatocarcinomas, 1 sarcoma, 1 hamartoma and 1 hemangioma were positive for cytokeratin no. 7, while cytokeratin 19 was present in 1 hepatocarcinoma and in the hamartoma. All these tumors, as well as 1 hepatoblastoma and the sarcoma, were also reactive for cytokeratin no. 8, typical of hepatic cells.