Treatment of chronic non-A, non-B hepatitis with interferon

Hepatitis-C-virus genotypes and hepatitis-G-virus infection in Lebanese thalassaemics

Exposure to hepatitis C virus (HCV), hepatitis G virus (HGV) and the carrier 'rate' for hepatitis B virus (HBsAg) were investigated in thalassaemia patients in Lebanon, a group that has not been studied in the past. The HCV genotypes and their distribution in the 395 thalassaemics, all of whom had been registered at the Chronic Care Center (CCC) in Hazmieh since 1996, were also studied. Of the 55 samples (14%) found positive for anti-HCV, 19 were also positive for HCV RNA. The 19 samples of HCV RNA were mostly of genotype 4 (37%), followed by 1a and 3a (21% each), lb (16%) and 2b (5%). Most (14; 74%) of the 19 HCV-RNA-positive samples, but only 13 (36%) of the 36 samples that were negative for HCV RNA although anti-HCV-positive, were positive for anti-HGV. Among 100 anti-HCV-negative samples, eight (8%) were anti-HGV positive. Only one (0.28%) of all 395 patients investigated was found to be HBsAg-positive. All of the HBV- and HCV-positive patients had initially been found positive in 1996, when they were first registered at the CCC, and none of the remaining patients had seroconverted since. As none of the patients had been checked for anti-HGV until the present study, the history of their exposure to HGV was unknown. These results emphasise the importance of screening all blood donations collected in Lebanon for HBsAg and anti-HCV. This and stringent infection-control measures are necessary steps to limit the spread of HBV, HCV and perhaps HGV to thalassaemics.

Clinical significance of hepatitis C virus genotypes

On the basis of phylogenetic analysis of nucleotide sequences, multiple genotypes and subtypes of hepatitis C virus (HCV) have been identified. Characterization of these genetic groups is likely to facilitate and contribute to the development of an effective vaccine against infection with HCV. Differences among HCV genotypes in geographic distributions have provided investigators with an epidemiologic marker that can be used to trace the source of HCV infection in a given population. HCV genotype 1 may represent a more aggressive strain and one that is less likely to respond to interferon treatment than HCV genotype 2 or 3. However, these observations require confirmation before HCV genotyping can be used in clinical settings.

Clinical significance of hepatitis C virus genotypes

On the basis of phylogenetic analysis of nucleotide sequences, multiple genotypes and subtypes of hepatitis C virus (HCV) have been identified. Characterization of these genetic groups is likely to facilitate and contribute to the development of an effective vaccine against infection with HCV. Differences among HCV genotypes in geographic distributions have provided investigators with an epidemiologic marker that can be used to trace the source of HCV infection in a given population. HCV genotype 1 may represent a more aggressive strain and one that is less likely to respond to interferon treatment than HCV genotype 2 or 3. However, these observations require confirmation before HCV genotyping can be used in clinical settings.

Hepatitis C genotypes: current trends and future implications

OBJECTIVE

To review the geographic distribution and current understanding of hepatitis C virus (HCV) genotypes in regard to liver disease activity and response to treatment.

MATERIAL AND METHODS

We review the relevant medical literature and discuss our recent findings relative to chronic HCV infection and the importance of HCV genotypes.

RESULTS

HCV genotypes 1a and 1b are the most commonly found genotypes in patients with chronic HCV in the United States. Infection with HCV genotype 1b may be associated with more severe liver disease and may have a higher risk for the development of hepatocellular carcinoma. HCV genotype 2b seemed to be the most sensitive and HCV genotype 1b was the least sensitive to interferon therapy.

CONCLUSION

The identification of the infectious HCV genotype may be beneficial in clinical settings and may assist in the selection of patients who would benefit from interferon treatment.