Objective: To identify predictors of a long-term response to interferon-alpha therapy in chronic hepatitis C and to determine whether hepatitis C virus (HCV) was eradicated in patients with chronic hepatitis C who had a long-term response to therapy.
Design: A retrospective analysis.
Setting: In- and outpatient liver clinic of a municipal hospital in Japan.
Patients: 47 patients with chronic hepatitis C who responded to interferon-alpha were divided into two groups: 22 patients with a long-term response (serum aminotransferase levels remained normal for > 1 year after therapy) and 25 patients with a short-term response (serum aminotransferase levels increased again after therapy).
Measurements: Genotyping of HCV, titers of HCV RNA in liver and serum samples (using the reverse transcriptase-polymerase chain reaction), histologic activity index, and liver histologic tests during and 1 year after therapy.
Results: Among the 22 long-term responders, HCV RNA was no longer detectable in liver and serum samples of 21 (95%) at the end of therapy and remained undetectable in the serum of 20 (91%) and in the liver of 19 (86%) 1 year after therapy. Liver histologic tests improved substantially immediately after therapy and 1 year after therapy in the long-term responders; however, 18 (82%) of these patients still had mild, chronic hepatitis. Among the 25 short-term responders, HCV RNA was still detected in the liver of 19 (76%) and in the serum of 9 (36%) at the end of therapy. Multivariate logistic regression analysis showed that the persistent presence of hepatic HCV RNA at the end of therapy was the strongest predictor of relapse.
Conclusion: These findings suggest that HCV infection was eradicated in most of the long-term responders to interferon-alpha therapy because HCV RNA could no longer be detected in their serum and liver samples and because a significant improvement gradually occurred in their liver histologic results. The persistent presence of hepatic HCV RNA at the end of therapy was the most important predictor of relapse.