Prevalence of mixed infection by different hepatitis C virus genotypes in patients with hepatitis C virus-related chronic liver disease

Multiple infection by different hepatitis C virus (HCV) genotypes may be of great clinico-pathologic interest. In this study we determined the effective prevalence of coinfections by two or more HCV genotypes in 213 subjects with HCV-positive chronic hepatitis by using genotype-specific polymerase chain reaction (PCR), genotype-specific probe hybridization, and direct sequencing. The most prevalent genotype was HCV-1b (54%). HCV-2 (a/c) was also prevalent (27%), and types 1a and 3a were found in 5% and 3% of patients, respectively. A mixed infection was detected in 23 patients (10.8%): 4 out of 23 were coinfected by types 1a + 1b, while the remaining 19 patients had a b + 2 (a/c) mixed infection. Further analysis based on restriction fragment length polymorphism (RFLP) on type-specific PCR products was used to verify genotyping results. Only four coinfections (1a + 1b in 2 patients and 1b + 2 (a/c) in the remaining 2 patients, respectively) were confirmed by enzyme cleavage. All patients with true coinfection had long-lasting infection and liver cirrhosis. Both true and false mixed infections resulting from RFLP analysis were confirmed by direct sequencing of type-specific amplification products. We also determined a recurrent C/T transversion at position 618 in all sequenced samples. In 4 cases another point mutation (G/A at position 626) was found, reducing the number of mismatches between HCV-2 and HCV-1b from 4 to 3 (or 2). Interestingly, all HCV-2 isolates sequenced showed the highest degree of nucleotide homology with HCV-2 subtype c, confirming the relatively high prevalence of this subtype in Italy. In conclusion, we showed the possibility of multiple infection by different HCV types in the general population of chronically infected patients without particular risk factors, even if in a low percentage of cases. Further studies are needed to assess the clinical relevance of chronic HCV infection with multiple genotypes.

Interferon and thymosin combination therapy in naive patients with chronic hepatitis C: preliminary results

AIMS/BACKGROUND

This randomized study was performed to compare the efficacy of interferon-alpha (IFN-alpha) + thymosin alpha 1 (Talpha1) treatment to that of IFN-alpha alone in light of biochemical and virological response of naive patients with chronic hepatitis C.

METHODS

Seventeen patients were treated with IFN alpha-2b (3 million units MU three times a week) + Talpha1 (1 mg twice weekly); the other 17 patients received only IFN alpha-2b at the same dose. All patients were treated for 6 months and followed up for 12 months. Biochemical (ALT values) and virological (HCV-RNA) responses to treatment were determined.

RESULTS

Combination therapy showed significantly higher efficacy than monotherapy in achieving biochemical and virologic end-of-treatment response (p<0.05). At 12 month follow-up, the sustained biochemical response was slightly greater in patients treated with combination therapy than in those treated with monotherapy. No significant difference in response by HCV-1b subtype was observed between the two treatment groups; however, HCV-2c subtype showed a trend to responding better to IFN-alpha+Talpha1 than to IFN-alpha alone.

CONCLUSIONS

These data suggest that the immune modulator Talpha1 may be additive or synergistic with IFN-alpha in normalizing end-treatment biochemical and virological responses in patients with chronic hepatitis C. Higher doses and/or more prolonged courses may improve the sustained response rates to this treatment.

Impaired response to alpha interferon in patients with an inapparent hepatitis B and hepatitis C virus coinfection

The possibility of hepatitis B virus (HBV) infection in HBsAg-negative patients has been shown. However, an "inapparent" coinfection by HBV in hepatitis C virus (HCV)-positive patients generally is not taken into account in clinical practice. Mechanisms responsible for resistance to interferon (IFN) have not been completely clarified. The aim of this study was to investigate whether an "inapparent" coinfection by HBV in anti-HCV-positive chronic liver disease patients may influence IFN response. Fourteen anti-HCV positive, HBsAg-negative but serum HBV DNA-positive patients by PCR and 111 anti-HCV-positive, HBsAg-negative and HBV DNA (PCR)-negative patients with chronic hepatitis were treated with 3 MU of recombinant alpha-2a IFN 3 times weekly for 12 months. Serum HBV DNA and HCV RNA were determined before treatment, after 6-12 months and in coincidence with ALT flare-up by PCR. HBV PCR was performed using primers specific for the S region of the HBV genome and HCV PCR with primers localised in the 5'NC region of HCV genome. IgM anti-HBc was tested using IMx Core-M Abbott assay. By the end of treatment, ALT values had become normal in 4/14 HBV DNA-positive patients (28%), but all "responders" (4/4) relapsed between 2 and 5 months after therapy. All but one patient were HCV RNA-positive before treatment, 6 were also both HBV DNA and HCV RNA-positive during ALT flare-ups. In 5 patients, only HBV DNA and in 3 patients, only HCV RNA was detected when transaminase values increased. All patients remained HBsAg-negative and anti-HCV-positive. IgM anti-HBc was detected both before treatment and during ALT elevation in 3 patients and only during ALT relapse in 3 others. Of the 111 anti-HCV positive, HBsAg-negative and HBV DNA (PCR)-negative patients with chronic hepatitis, a biochemical response to IFN treatment was observed in 54% of the cases. Relapse of ALT values was observed in 47% of the cases during a follow-up of 1 year after treatment. "Inapparent" HBV/HCV coinfection may be implicated in cases of resistance to IFN treatment. In addition, HBV replication may persist in patients in whom HCV replication was inhibited by IFN treatment. The pathogenic role of HBV in liver disease was confirmed by detection of IgM anti-HBc in some cases; the appearance of these antibodies only after IFN treatment suggests that IFN may exert a selective role in favour of HBV. Further studies will show the effect of different treatment schedules. HBV DNA and/or IgM anti-HBc detection with very sensitive methods may be important both as a prognostic factor and as a tool for better understanding interviral relationships and mechanisms involved in multiple hepatitis virus infections.

Hepatitis C virus infection in mixed cryoglobulinemia and B-cell non-Hodgkin's lymphoma: evidence for a pathogenetic role

We investigated the pathogenetic relevance of hepatitis C virus (HCV) infection in mixed cryoglobulinemia (MC) with or without complicating B-cell Non-Hodgkin's lymphoma (NHL) in comparison with other immunological and lymphoproliferative disorders. The following groups of patients were studied: A) 25 patients with MC in 7 cases evolved into B-cell NHL; B) 25 healthy subjects; C) 22 patients with different systemic immune diseases; D) 24 patients with chronic HCV infection without MC; E) 25 patients with B-cell idiopathic NHL. Methods used included: i) Polymerase chain reaction (PCR) for HCV RNA detection in serum and peripheral blood mononuclear cells (PBMC) (uncultured or mitogen-stimulated); ii) Branched DNA (b-DNA) for HCV RNA quantification; iii) HCV genotyping by genotype-specific primers localized in the core region and by hybridization of amplification products of the 5' untranslated region (5'UTR), obtained with universal primers, using genotype-specific probes. Serum anti-HCV and HCV RNA were detected in 88% and 73% of MC patients, respectively, and in a significantly lower percentage of healthy controls and patients with autoimmune diseases. HCV RNA concentration was significantly lower in supernatants than in corresponding whole sera (p < 0.001). Plus-strand HCV RNA was detected in 81% of peripheral blood mononuclear cell (PBMC) samples and minus-strand in the majority of fresh or mitogen stimulated cells. All MC patients with NHL had HCV RNA sequences in PBMC. HCV genotype 2a/III was detected in MC patients with a prevalence that was significantly higher than in HCV infected patients without MC. Surprisingly, HCV markers (anti-HCV and/or HCV RNA) were found in 32% of patients with idiopathic NHL. These data suggest that HCV infection is involved in the pathogenesis of MC through both direct participation in the immune complex related vasculitis and by triggering the lymphoproliferative disorder underlying the disease. This latter disorder seems to be related to HCV lymphotropism which could also be responsible for the evolution of MC to malignant lymphoma. This study also suggests that HCV infection may be involved in the pathogenesis of idiopathic B-cell NHL through a similar pathogenetic mechanism.

Serum HCV-RNA and liver histologic findings in patients with long-term normal transaminases

In this study we aimed to correlate liver histology and the presence of hepatitis C virus (HCV) viremia, genotype, and quantity of HCV genome in 19 positive and 11 RIBA II indeterminate patients presenting persistently normal ALT values over 24 months before biopsy. In addition, after biopsy serum ALT values were monitored monthly for a mean follow-up period of 24.8 months, after which patients were reevaluated for RIBA II and the presence of viremia. Sixteen patients (53%) were serum HCV-RNA-positive; 13 of them (68%) were confirmed positive and 3 (27%) indeterminate on RIBA II. Histology of the HCV-RNA-positive patients showed eight cases of CPH (one case of genotype 1a; four cases type 1b; three cases type 2), six cases of CAH (three cases type 1b, three cases type 2), one case of CLH (type not determined), and one case of normal liver (NL) (type 1b). Histology of the HCV-RNA-negative patients showed four cases of CPH, one case of CAH, two cases of CLH, and seven cases of NL. During the follow-up period nine patients (30%) presented slight increases in ALT values (< 2 x N), and in particular, flares of ALT were observed four times in the CAH and five times in the CPH patients, who were all viremic, but never in the NL subjects. These results indicate that subjects positive on RIBA II, but with persistently normal ALT values, had a high probability of being serum HCV-RNA-positive and that almost all these viremic subjects presented histologic signs of liver disease. In contrast, RIBA II indeterminate subjects had a moderate probability of being HCV-RNA-positive, but a number of these may present signs of liver disease. In both cases there was no association with genotype or HCV-RNA serum levels. The other nonviremic cases included subjects with hepatic changes going toward resolution or with normal liver in whom hepatic biopsy can be avoided. Only one case was a true carrier since he was viremic with normal liver and persistently normal ALT values.

Relevance of inapparent coinfection by hepatitis B virus in alpha interferon-treated patients with hepatitis C virus chronic hepatitis

The aim of the study was to investigate whether an "inapparent" coinfection by hepatitis B virus (HBV) in anti-HCV-positive chronic liver disease patients may influence interferon (IFN) response. Fourteen anti-HCV-positive, hepatitis B surface antigen (HBsAg)-negative but serum HBV-DNA-positive patients and 111 anti-HCV-positive, HBsAg-negative, and HBV-DNA-negative patients with chronic hepatitis were treated with 3 MU of recombinant alpha-2a IFN 3/week for 1.2 months. Serum HBV-DNA and HCV-RNA were determined before treatment, after 6-12 months, and at the time of alanine aminotransferase (ALT) flare-up by HBV polymerase chain reaction (PCR) and HCV PCR, respectively. IgM anti-HBc were tested using the IMx Core-M assay (Abbott Laboratories, North Chicago, IL). By the end of treatment, ALT values had become normal in 4/14 HBV-DNA-positive patients (28%), but all "responders" (4/4) relapsed. IgM anti-HBc was detected both before treatment and during ALT elevation in three patients and only during ALT relapse in another three. In the remaining 111 patients, a biochemical response to IFN treatment was observed in 54% and relapse of ALT values in 47%. "Inapparent" HBV/HCV coinfection may be implicated in cases of resistance to IFN. HBV replication and HBV-related liver damage may persist in patients in whom HCV replication was inhibited by current doses of IFN, as suggested also by the presence of IgM anti-HBc in some cases. Further studies will show the effect of different treatment schedules. HBV-DNA and/or IgM anti-HBc detection with very sensitive methods may be important both as a prognostic factor and as a tool for better understanding of intervirus relationships and mechanisms involved in multiple hepatitis virus infections.

Lymphotropic virus infection of peripheral blood mononuclear cells in B-cell non-Hodgkin's lymphoma

Some lymphotropic viruses such as Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6) have been proposed as causative agents of B cell non-Hodgkin's lymphoma (NHL). More recently, the presence of hepatitis C virus (HCV), which is both a hepatotropic and lymphotropic virus, has been reported in one third of B cell NHL patients. The aim of this study was to investigate in a series of B cell NHL the prevalence of three lymphotropic viruses, i.e. EBV, HHV-6 and HCV, in peripheral blood mononuclear cells (PBMC). Eighteen unselected B cell NHL patients (10 men, 8 women; mean age 62 +/- 12 years, range 31-77 years; mean disease duration 1.8 +/- 1.4 years) and 40 age- and sex-matched healthy controls were included in the study. In all cases, an acquired-immunodeficiency-syndrome-related lymphoma was excluded. By means of the polymerase chain reaction technique, EBV DNA, HHV-6 DNA and HCV RNA were detected in PBMC. HCV genomic sequences were significantly more frequent in PBMC of NHL patients than in controls (33 vs. 2.5%; p < 0.01); on the other hand, in the same two groups EBV DNA (39 vs. 60%; p = not significant) and HHV-6 DNA (22 vs. 32%; p = not significant) were present in a comparable percentage of individuals in the same two groups. The infection of PBMC by HCV alone was present in the majority (5 of 6) of HCV-positive NHL. These data support the implication of HCV infection in a statistically significant number of B cell NHL, whereas a possible co-operation between HCV and other well-known lymphotropic viruses seems to be excluded.

Hepatitis C virus genotype analysis in patients with type II mixed cryoglobulinemia

OBJECTIVE

To investigate the possible role of HCV variants in the pathogenesis of mixed cryoglobulinemia.

SETTING

Medical service (rheumatology and hepatology units) of urban, university-affiliated teaching hospitals.

DESIGN

Analysis of viral genotypes in a cohort of patients with hepatitis C virus (HCV) infection and mixed cryoglobulinemia.

PATIENTS

90 unselected HCV-positive (anti-HCV antibody-positive and HCV RNA-positive) patients consecutively recruited at routine ambulatory visits: 29 with and 61 without (control group) mixed cryoglobulinemia.

MEASUREMENTS

Clinical and histologic data; HCV RNA detection in serum and peripheral blood mononuclear cells by polymerase chain reaction (PCR); HCV genotype determination by two methods based on genotype-specific primer PCR and genotype-specific probe hybridization, respectively.

RESULTS

Persistent aminotransferase increases were found in 55% of patients with mixed cryoglobulinemia. Peripheral blood mononuclear cells were infected in 80% of cases. In serum samples, HCV genotype 2a/III was detected with a higher prevalence in patients with mixed cryoglobulinemia than in controls (41% compared with 15%). The overall prevalence of genotype 2a/III in mixed cryoglobulinemia increased to 52% when findings in peripheral blood mononuclear cells were also considered. Among patients with mixed cryoglobulinemia, this genotype was more frequent in those without clinical and biochemical signs of liver disease (85%) or with serum autoantibodies (75%).

CONCLUSIONS

Mixed cryoglobulinemia may be related, at least in part, to the HCV genotype infecting the host.

Hepatitis C virus as a lymphotropic agent: evidence and pathogenetic implications

Hepatitis C virus has been proven to be the major cause of NANB hepatitis, cirrhosis and hepatocellular carcinoma worldwide. Based on the genome similarities between HCV and flavivirus or pestivirus, this agent has been included within the family Flaviviridae as a separate genus. Among the analogies between HCV and the other members of the same family there is the possibility of infecting blood cells. In particular, significant evidence obtained through studies performed in vivo and in vitro support the concept that HCV is not only a hepatotropic but also a lymphotropic virus. This suggests that, in addition to playing a role in inducing hepatic diseases (both of a non-tumoral and a neoplastic nature), HCV infection may also play a role in extrahepatic pathologies. The striking association observed between HCV infection and some autoimmune-lymphoproliferative disorders of either benign or neoplastic nature is consistent with this hypothesis. However, in analogy with what has been observed in the case of liver disease, the mechanisms involved in the pathogenesis of HCV-related extra-hepatic manifestations have to be more deeply analysed and clarified.

Hepatitis C virus infection of mononuclear cells from peripheral blood and liver infiltrates in chronically infected patients

The mechanisms underlying chronicity of hepatitis C virus (HCV) infection are poorly understood, but the importance of impaired viral clearance by the immune system has been suggested. The prevalence of HCV infection of peripheral blood mononuclear cells (PBMC) was in investigated in 34 persistently infected patients with anti-HCV (7 with liver cirrhosis, 10 with chronic active hepatitis, 5 with chronic persistent hepatitis, 4 with chronic lobular hepatitis, and 8 healthy carriers) by polymerase chain reaction (PCR). HCV infection of 116 T cell clones derived from liver infiltrating mononuclear cells obtained from 3 patients with chronic liver disease was examined using the same methods. HCV genomic sequences were found in fresh, unstimulated PBMC from 20 patients with cirrhosis, and chronic active and persistent hepatitis, but in none of the healthy carriers and only in mitogen-activated cells from 1 out of 4 patients with autoresolving chronic lobular hepatitis. Active PBMC infection was confirmed by identification of anti-genomic HCV sequences in the majority of HCV RNA-positive cells (fresh or mitogen-stimulated). A high percentage of T cell clones obtained from liver infiltrates were found to be infected by HCV. These findings suggest that HCV infection of lymphatic cells plays a role in the pathogenesis of chronically evolving liver damage. PBMC may represent a reservoir for latent infection and a site for viral multiplication.

"Inapparent" hepatitis B virus infection and hepatitis C virus replication in alcoholic subjects with and without liver disease

We evaluated hepatitis B virus DNA and hepatitis C virus RNA in sera from 110 HBsAg and IgM HBc antibody-negative heavy drinkers (50 cirrhosis, 13 chronic active hepatitis, 25 fatty liver with or without mild to moderate fibrosis, alcoholic hepatitis or both and 22 healthy alcoholic subjects) with polymerase chain reaction. Results of hepatitis C virus polymerase chain reaction were compared with those obtained with two tests (second generation recombinant immunoblot assay and enzyme-linked immunosorbent assay) used to detect hepatitis C virus antibodies. Hepatitis B virus DNA was found in three (2.7%) patients. Hepatitis C virus RNA was detected in 29 (29.8%) of the 97 subjects whose sera were well preserved for RNA extraction (42.5% cirrhosis, 83.3% chronic active hepatitis, 8% fatty liver and 0% healthy alcoholic subjects). Results obtained with second-generation recombinant immunoblot assay and enzyme-linked immunosorbent assay had a high degree of agreement with polymerase chain reaction as expected, the kappa indexes being 0.76 and 0.61, respectively. Nevertheless, five hepatitis C virus RNA-positive patients had negative recombinant immunoblot assay results, whereas all hepatitis C virus RNA-positive patients had positive or borderline enzyme-linked immunosorbent assay results. We conclude that, in Italian HBsAg-negative alcoholic patients, "inapparent" hepatitis B virus infection is rare. On the contrary, hepatitis C virus infection, as detected on hepatitis C virus polymerase chain reaction, is quite frequent, especially in patients who have cirrhosis and chronic active hepatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus-related autoimmunity in patients with porphyria cutanea tarda

Hepatitis C virus (HCV) infection is frequently found in autoimmune hepatitis and mixed cryoglobulinaemia. In these conditions HCV could be responsible for immuno-mediated organ alterations. The aim of this study was to evaluate the presence of immunological alterations in PCT patients, in which HCV infection has been frequently found. Twenty-three PCT patients were evaluated for clinical and serological alterations, including: chronic hepatitis, other systemic symptoms, serum cryoglobulins and rheumatoid factor (RF), haemolytic complement, serum immunoglobulins, anti-nuclear (ANA), anti-smooth muscle (ASMA), anti-liver-kidney-microsomal (anti-LKM1), anti-soluble-liver-antigen (SLA), anti-mitochondrial (AMA), anti-GOR antibodies, anti-HCV and HCV RNA. Abnormal serum ALT were present in the majority of cases (20/23, 87%), while liver biopsy revealed a chronic persistent hepatitis or chronic active hepatitis in 15/20 (75%) PCT patients. In a high percentage of subjects (91%) the presence of anti-HCV was detected by ELISA and RIBA II (Chiron, Emeryville CA, USA). In 17/22 (77%) cases the ongoing HCV replication in the serum was demonstrated by the detection of HCV genomes (polymerase chain reaction). The prevalence of both anti-HCV and HCV RNA in PCT was significantly higher if compared to 22 systemic immunological diseases (P < 0.001) and 47 healthy subjects (P < 0.001). A possible HCV-induced autoimmunity in PCT was suggested by the presence of the following immunological parameter alterations: anti-GOR in 13/23 (57%), ANA in 4/23 (17%), ASMA in 18/23 (78%), anti-LKM1 in 1/23 (4%), RF in 23/23 (100%), mixed cryoglobulins in 4/23 (17%), complement consumption in 10/23 (43%).(ABSTRACT TRUNCATED AT 250 WORDS)