Different reactivity against HCV proteins (RIBA 3) according to progression of liver damage

BACKGROUND

Aim of the study was to assess the correlation between clinical stage of HCV-related liver disease and viraemia to immune response to different viral antigens.

METHODS

We considered 1330 patients with HCV chronic infection followed up from 6 months up to 6 years divided into two groups according to RIBA 3 (Abbott) response: Group I, 1231 patients with positivity for at least two bands (83 subjects with asymptomatic infection, 941 with chronic hepatitis, 201 with cirrhosis and 6 with HCC); Group II, 99 patients with positivity at only one band (45 with asymptomatic infection, 53 with chronic hepatitis and 1 cirrhotic).

RESULTS

We noticed a major percentage of positive patients for at least three bands in more severe clinical forms (90% of chronic hepatitis or cirrhosis versus 60% of asymptomatics, p < 0.005, chi 2 test). Moreover we noticed a percentage increase of positivity for antibodies anti-c100 and anti-NS5 with the progression of liver damage, statistically significant differences between asymptomatics and patients with chronic forms. We also observed that viraemia is related neither to clinical stage nor to different reactivity to RIBA 3, albeit viraemia is usually detected more frequently among patients with liver damage, but unrelated to different reactivities.

CONCLUSIONS

Our results show a clear correlation between number of reactivities towards HCV proteins and progression of liver damage, pointing out that immune response plays a direct role in the long-term outcome of HCV infection.

IgM anti-hepatitis C virus in patients with chronic non-A, non-B hepatitis and their relationship to viral replication

Patients with hepatitis C virus (HCV) infection may have different patterns of antibody response to various structural and non-structural viral antigens. We have correlated the serological patterns to the clinical features of chronic infection and to viral replication in 68 HCV-Ab-positive patients with chronic liver disease at different stages (19 with cirrhosis-hepatocellular carcinoma, 38 with chronic active hepatitis and 11 with chronic persistent hepatitis). Serum samples from each patient were assayed for HCV-IgM by enzyme immunoassay and for HCV-RNA by the polymerase chain reaction using primer sets derived from the 5'-non-coding region. The prevalence of HCV-IgM was high (54 patients (79.4%)) and the study showed a good correlation between high values of anti-HCV-IgM and the presence of HCV-RNA in serum, since HCV-RNA was detected in 35 of the 54 IgM-positive patients (64.8%) and notably in 19 of the 20 subjects with high levels of specific IgM. Conversely, all the 35 sera containing HCV-RNA were also reactive for HCV-IgM, while none of the HCV-IgM-negative sera was HCV-RNA reactive. Positivity rates for both HCV-RNA and IgM anti-HCV were higher in the more advanced stages of disease; thus, the clinical pattern of HCV chronic hepatitis seems to be strictly related to the serological pattern and the presence of HCV-RNA.

Prevalence of anti-HCV in two Tanzanian villages

The presence of anti-HCV antibodies was investigated in sera from a total of 123 inhabitants of two Tanzanian villages. In one of the villages, 72.2% of the sera and in the other village, 82.6% of the sera were found to be anti-HCV positive. These values are dramatically higher than other reported prevalences, whereby cross-reactivity between HCV and Flaviviruses as well as possible transmission by arthropod vectors cannot be ruled out.