Rheumatic manifestations and immunological abnormalities in patients with chronic hepatitis C. A study in the Middle East.

: Hepatitis C virus infection and rheumatic disorders are both common in the Middle East and share many clinical and immunological manifestations, raising diagnostic problems. We compared the prevalence of extrahepatic clinical manifestations and immunological disorders in 40 patients with chronic hepatitis C and in 42 carefully matched healthy controls. Polyarthralgia or polyarthritis was the most common rheumatic manifestation (35%) in the cases, followed by cutaneous vasculitis (15%). Glomerulonephritis and xerophthalmia were uncommon, and none of the cases had systemic vasculitis. Immunological abnormalities included serum rheumatoid factor (47.5%), cryoglobulins (30%), and one or more antitissue antibodies (37.5%). The prevalences of polyarthralgia, cutaneous vasculitis, rheumatoid factor, cryoglobulinemia, and anti-tissue antibodies were significantly higher in the hepatitis C group than in the control group. Our data suggest that patients in the Middle East who present with features of rheumatic or autoimmune diseases should be screened for hepatitis C.