Extrahepatic immunologic manifestations in chronic hepatitis C and hepatitis C virus serotypes.

To determine, using a serotyping assay, whether the occurrence of extrahepatic immunologic disorders in patients with chronic hepatitis C is dependent on hepatitis C virus serotype. Prospective study. Liver unit and virology laboratory of a university hospital. 59 consecutive patients with chronic hepatitis C. Hepatitis C virus serotype was determined using a recently developed immunoenzymatic assay that detects antibodies directed to serotype-specific immunodominant epitopes. Cryoglobulin, rheumatoid factor, and numerous antitissue antibodies were sought. Biopsies of labial salivary glands were done in 49 of the 59 patients. Prevalence was 59% for serotype 1, 10% for serotype 2, 12% for serotype 3, and 3% for mixed infection. Fifteen percent of patients could not be serotyped. Cryoglobulinemia was found in 36% of patients and rheumatoid factor was found in the serum of 71%. At least one antitissue antibody was found in the serum of 41% of patients; salivary gland biopsy showed lymphocytic capillaritis in 49% of patients. These immunologic abnormalities were seen in patients infected with any of the three serotypes, and prevalences of the abnormalities did not differ significantly among patients infected with different serotypes. We confirm that the prevalence of extrahepatic immunologic abnormalities is high in patients with chronic hepatitis C. These abnormalities may occur in patients infected with any of the three major hepatitis C virus serotypes now present in developed countries.