Response to interferon alpha treatment and disappearance of cryoglobulinaemia in patients infected by hepatitis C virus

Background-Mixed cryoglobulinaemia is closely associated with hepatitis C v irus (HCV) infection. Aims-To assess in a prospective open study the efficiency of interferon a t reatment of cryoglobulinaemia, as reflected by the disappearance of cryoglo bulins and clinical manifestations of the disease, and to analyse the facto rs predictive of a response to interferon. Method-Eighty seven consecutive patients with chronic hepatitis C treated f or the first time with interferon at a dose of 3 x 10(6) international unit s three times a week for six months were studied. Forty three patients had cryoglobulins, which were responsible for clinical manifestations in 12. Results At the end of interferon treatment, cryoglobulins had disappeared i n 39% of the patients. A clinical improvement (except for neuropathies) was observed in all patients. Six months after interferon treatment was stoppe d, the same rate of response (normal alanine aminotransferase values and un dectable HCV RNA) was observed in patients with or without cryoglobulins. O nly 14% of patients still had undetectable cryoglobulins, and all of them a lso had undetectable serum HCV RNA. The disappearance of cryoglobulins was found less frequently in patients with clinical symptoms than in asymptomat ic ones, but the difference was not significant. Sustained responders were more often men, infected by genotype 2 or 3, with a lower pretreatment vira l load. Conclusion-The presence of cryoglobulins does not seem to affect the respon se to interferon in HCV infected patients. The improvement in cryoglobulina emia is strongly associated with a virological response, reinforcing the hy pothesis of a direct role for HCV in the pathogenesis of this disease.