Interferon-α treatment of hepatitis C virus-associated mixed cryoglobulinemia

Background/Aims: Chronic hepatitis C virus infection is frequently associated with mixed cryoglobulinemia. The efficacy of interferon-α treatment in the presence of cryoglobulinemia, particularly the rate of sustained responders, has not yet been well defined. Methods: Fifty-nine consecutive patients with chronic HCV infection were studied prospectively with regard to the presence of cryoglobulinemia and their biochemical and virological response to interferon-α2a therapy. Results: Cryoglobulins were detected in sera of 23 patients. For this latter group of patients, significant differences were found compared to the 36 patients without cryoglobulinemia, i.e. the prevalence of female sex was higher, the duration of liver disease was longer and distinctive laboratory abnormalities, e.g. higher rheumatoid factor activity, were noted as well as a higher prevalence of cirrhosis. The distribution of HCV genotypes and serum HCV RNA titers was similar in the two groups. Interferon-α treatment regimens were not different regarding mean cumulative dose and mean duration of therapy. The response to therapy was almost identical, i.e. 35% of patients with cryoglobulinemia showed a sustained response compared to 22% of patients without cryoglobulinemia. The percentages of patients showing a relapse or breakthrough were similar in both groups. Pre-treatment viremia levels were higher in non-responders compared to sustained responders. Non-responders appeared to be more frequent among patients infected with genotypes 1a and 1b, especially among male patients without cryoglobulinemia. Conclusions: The presence of cryoglobulinemia per se in chronic HCV-infected patients does not adversely affect the outcome of interferon-α therapy, including the rate of sustained response.