1. Cytokines are soluble factors whose action has been documented in physiological and pathological conditions. Some may be involved in the pathogenesis of cholestasis, whether of acute or chronic origin. 2. The aim of the present study was to evaluate the influence of epidermal growth factor (EGF), transforming growth factor (TGF)-beta 1, interleukin (IL)-6 and tumour necrosis factor (TNF) on cholestasis. Findings from Sprague-Dawley rats submitted to bile duct ligation for 1-28 days were compared with those from controls, which underwent laparotomy but not bile duct ligation. 3. Biochemical and morphological findings confirmed that the experimental procedure was successful. At the end of each follow-up period, the hepatic levels of the cytokines were determined and compared with liver histology findings. 4. The four cytokines studied showed different patterns of activation: hepatic levels of EGF, higher in the experimental than the control group, were comparable with the proliferative picture. The TGF-beta 1 pattern was correlated with data of periportal, perivenular and perineoductular fibrosis, confirming that this cytokine has a role in mediating the synthesis of matrix proteins. A fluctuating, phasic pattern was found for TNF in the experimental group, with high values on day 0, a decrease on the first and second postoperative days and then two peaks on days 8 and 14. Finally, immediately after surgical manipulation, high levels of IL-6 were found in the experimental group, followed by a decrease in levels until zero values were obtained. 5. This suggests that the obstructive condition produces several cytokine responses, each of which contributes to determine the cholestatic condition.

Prevalence and impact of occult HBV infection in HIV positive patients is controversial. The aims of this study were to determine the prevalence of occult HBV infection and its impact on histological and virological parameters. 52 HIV/HCV (but HBsAg-negative) co-infected patients, 29 HBsAg and anti-HCV negative chronic hepatitis, and 20 HBsAg positive chronic hepatitis controls were studied. DNA was extracted from frozen biopsies and amplified with primers for S, C and X regions, and for (ccc) HBV-DNA. Sera were tested for HBV-DNA with two quantitative assays (Cobas Amplicor HBV Monitor, and the real-time COBAS (r) Taqman HBV Test, Roche Diagnostics, UK). Occult HBV infection was detected in 7 (13.4%) liver biopsies of the study group, and in none case of the non viral chronic hepatitis group (p=0.04). All serum samples were HBV-DNA negative with Cobas Amplicor HBV monitor assay, while 3 cases were found positive with real time PCR. Statistical analysis didn't show any impact of occult HBV infection on liver histology, CD4+ cells count, HIV and HCV load, and ALT levels. Occult B infection is relatively frequent in HIV/HCV co-infected patients, and is underestimated by common HBV-DNA serological assays. However, it doesn't seem to exert a relevant impact.

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.

The findings that the same genotype was detected for both partners in relatively few couples, and that a history of parenteral exposure was an independent predictor of HCV positivity, suggest that the risk of sexual transmission is low. The sharing of glass syringes may have played an important role in transmission between spouses.

The characteristics of genotype 4 subtype variability of HCV isolates circulating in Italy were studied. The viral isolates were identified from 736 HCV-RNA positive sera originated from seroepidemiological studies undertaken in 4 different regions of North, South Italy and Sardinia. 24 out of 28 genotype 4 isolates (86%) were classified by phylogenetic analysis of E1 genome region (915-1128) as belonging to subtype 4d (Neighbour Joining Method). Three isolates classified as subtype 4a were detected in haemophilic patients, possibly related to infections from blood products. One isolate classified as a new subtype derived from an Eritrean patient subjected to haemodialysis. Very high genome homogeneity (mean 4.3%) was shown by genetic comparisons (DNA dist programs Phylip Package) for all the 4d isolates relative to the studies performed in Veneto, Calabria and Sardinia and originated from subjects from the general population and outpatients (19 subtype 4d isolates out of 24). In the 3 studies different prevalence rates of HCV genotype 4 (3.1%, 1. 3%, 14% respectively) were found. In contrast a considerable degree of heterogeneity, both intragroup and with the other groups (mean 8. 2% and 8.7%, respectively) was observed among subtype 4d isolates identified in the patients of a haemodialysis centre in Apulia region. In conclusion the subtype 4d of genotype 4 was highly prevalent and endemic in Italy. An elevated level of viral heterogeneity was observed in one study carried out in a region of Southern Italy. This can be related to a longer period of past endemicity of this genotype and to a high level of exposure to reinfections in particular categories of patients such as haemodialysis patients.