High prevalence of HCV-RNA in the saliva cell fraction of patients with chronic hepatitis C but no evidence of HCV transmission among sexual partners.

The aims of this study were to evaluate the prevalence of HCV-RNA in different fractions of saliva taken from patients with chronic hepatitis C, to establish whether virologic parameters or disease severity exert any influence on the detectability of HCV-RNA in saliva, and to evaluate the prevalence of HCV infection in partners of HCV-infected subjects with respect to the presence of HCV-RNA in saliva. Sera samples and different fractions of saliva (whole saliva, surnatant, and cell fraction) from 48 subjects (45 with chronic hepatitis C and three healthy anti-HCV+ carriers) were examined for HCV-RNA by RT nested PCR and DEIA hybridization. HCV-RNA-positive sera were also tested for genotype and viral titer (bDNA2 method). Twenty-seven stable sexual partners (25 females and 2 males) were screened for anti-HCV antibodies at least twice over a minimum of 12 months. HCV-RNA was detected in the sera of 39/45 patients and of 22/39 viremic patients. In all of the latter, the presence of HCV-RNA was restricted to the cell fraction. Viral titer was significantly higher in patients with HCV-RNA in saliva than in those without (12.3 x 10(6) versus 4.6 x 10(6) eq/ml, P < 0.01). HCV-RNA positivity was unrelated to genotype, duration of disease, Hepatitis Activity Index scores or transaminase levels. Anti-HCV was positive in one of 13 sexual partners of patients with HCV-RNA in saliva and in 1/14 of those without (P = NS). In conclusion, HCV-RNA is detectable in the cell fraction of saliva in a high proportion of highly viremic patients with chronic hepatitis C, but its presence does not seem to be associated with an increased risk of HCV transmission among sexual partners.

HGV/GBV-C in liver tissue and in sera from patients with chronic hepatitis C.

Forty-eight persons (M = 45, F = 3; age range = 20-53, mean = 32.2) affected with chronic hepatitis C were tested for HGV/GBV-C RNA and HCV-RNA by nested PCR and DEIA in serum and in liver specimens to evaluate the prevalence and the impact of HGV/GBV-C coinfection in patients with chronic HCV-related hepatitis. Sera were also assayed for antibodies to HGV/GBV-C E2 protein. Serum HGV/GBV-RNA could be detected in nine (19%) patients, and anti-E2 antibodies in 22 (46%) patients. The presence of HGV/GBV-C RNA or anti-E2 antibodies was mutually exclusive. The cumulative prevalence of HGV/GBV-C infection was 65% (31/48); the majority of these patients (26/31, 84%) were intravenous drug users (IVDUs). In eight of nine patients viraemic for HGV/GBV-C, RNA positivity could be revealed even in liver specimens; these eight patients were also positive for HCV-RNA both in serum and the liver and did not exhibit any specific association with HCV genotype. HGV/GBV-C RNA negative strand RT-PCR testing was negative in all of the eight liver specimens, providing little support to the hypothesis that liver represents the primary site of HGV/GBV-C replication. Moreover, patients with HGV/GBV-C and HCV coinfection were comparable to those with HCV infection alone in terms of biochemistry and liver histology.

HGV/GBV-C infection in patients with acute hepatitis of different etiology and in patients with chronic hepatitis C.

To investigate the prevalence of hepatitis G virus (HGV/GBV-C) in patients with liver disease and to confirm its hypothesized ability to cause liver damage, we studied 130 subjects; 61 had chronic hepatitis C virus infection and 69 had acute hepatitis of either defined etiology (n = 57) or of unknown origin (n = 12). Positivity for HGV/GBV-C RNA was detected in 10 of the 61 subjects with chronic hepatitis C (16.3%) and in 11 of the 57 subjects with acute hepatitis of defined etiology (19%), whereas we failed to detect HGV/ GBV-C viremia in subjects with hepatitis of nonestablished etiology. Patients exhibiting positivity for HGV/GBV-C RNA were found to be comparable to those exhibiting negativity for HGV/GBV-C RNA in terms of both liver function tests and Knodell's score (in liver biopsies); the affect of HGV/GBV-C infection on the biohumoral and histological activity in patients with chronic hepatitis C therefore appears to be minimal or absent. Similar clinical features were observed in patients with acute hepatitis of known etiology whether they were positive or negative for HGV/GBV-C RNA. However, long-term clinical studies are still required to clarify the actual impact of HGV/GBV-C co-infection. In our geographic, i.e., a region or north-east Italy, HGV/GBV-C infection appears to be strictly related to intravenous drug use, and this agent does not seem to be responsible for acute hepatitis of unknown etiology; other etiological agents are probably involved.

A DNA hybridization method for typing hepatitis C virus genotype 2c.

A high prevalence of hepatitis C virus (HCV) genotype 2c (22%) was detected in sera from 459 italian patients by core-region amplification and hybridization with specific probes by DNA enzyme immunoassay. Amplified fragments failed to hybridize with 1a, 1b, 2a, 2b and 3a subtype-specific and 4, 5, 6 type-specific oligonucleotides in 105 patients. Hybridization of these samples with type 2 probe, which recognized all the subtypes sequences, showed evidence for genotype 2 distinct from 2a and 2b. Fourteen out of these 105 isolates were cloned and sequenced. The results were consistent with genotyping assay. Nucleotide sequences were partially related to types 2a, 2b, 2d, 2e and 2f (87.0-93.5% of identity). The average nucleotide identity was highest for genotype 2c (95.87%). On the basis of sequence analysis, subtype 2c specific probe was derived. Hybridization efficiency with the newly designed probe was very high and more than 95% (100/105) of type 2 cases were classified as 2c. Evidence of different outcome of therapy inside the same HCV major type account for the need of accurate subtyping. In this study, amplification of the core region followed by hybridization with highly specific probes enabled distinction between HCV subtypes.