Hepatitis C virus (HCV) has been associated with several autoimmune and rheumatologic disorders. The aim of this study was to determine the incidence of these abnormalities in patients with chronic HCV. We studied 56 patients, 29 of whom (52%) had biochemical abnormalities that suggested immunological disorders. Cryoglobulinemia was detected in nine patients (22%), antinuclear antibodies in eleven (20%), rheumatoid factor in seven (19.27%) and hypocomplementemia in fourteen (29.16%). The most common clinical manifestations were: arthralgias (52%), myalgias (16%), xerostomia (28.5%) and xerophthalmia (14%). These results indicate the existence of a relationship between HCV and rheumatologic disorders. We conclude that HCV may play a role in the pathogenesis of these autoimmune phenomena, but more studies are required to define the extent of this role.