Objective: To evaluate the relationship between hepatitis C virus (HCV)-RNA levels and genotypes in order to establish their potentially predictive role in interferon (IFN) response.
Design: To detect HCV genotype at baseline and HCV viraemia levels before and during IFN treatment in three groups of patients with different IFN response.
Methods: Our study included 85 patients with biopsy-proven chronic hepatitis C who underwent IFN therapy at standard schedule (3 MU thrice weekly for 6 months). On the basis of IFN response they were subdivided into three groups as follows: non responders (NR: 27 cases) when alanine aminotransferase (ALT) values (normal value: 0-40 IU) at the end of treatment were abnormal (101.7 +/- 10.4); responders relapsing (RR: 29 cases) when normal ALT values at the end of therapy (28.14 +/- 1.7) increased during follow-up; sustained (long-term) responders (LTR: 29 cases) when ALT values remained normal for at least 12 months of follow-up (ALT values at the end of therapy: 21.8 +/- 1.4). ALT activity was monitored monthly during therapy and each month during 12 months of follow-up. HCV genotype was evaluated before starting treatment whereas HCV-RNA viraemia was checked at baseline and at the 1st and 6th months of therapy.
Results: The baseline viral load was higher in the NR group than in the RR and LTR groups independently of genotype; HCV-RNA levels progressively decreased during therapy independently of response but the levels remained significantly higher in the NR group. Genotype 1b was prevalent in the NR group. However, levels of viraemia in genotype 1b LTR patients are significantly lower than in genotype 1b NR patients.
Conclusion: These results suggest that among viral-related parameters viraemia alone seems to play an important role in predicting response to IFN independently of genotype.