Prevalence of hepatitis C virus infection in patients with rheumatoid arthritis

Background: Various viruses have been implicated in the cause and pathogenesis of rheumatoid arthritis (RA). Hepatitis C virus (HCV) infection, which has been recognised as a cause of some autoimmune diseases, and which has been described as sometimes presenting with rheumatic manifestations indistinguishable from RA, might be a candidate. Objective: To evaluate the prevalence of HCV infection in patients with RA. Methods: Consecutive patients with RA admitted to hospital in two departments of rheumatology were prospectively studied. Patients' serum samples were screened for the presence of anti-HCV antibodies. Patients with positive serology were further evaluated for the presence of HCV ribonucleic acid by reverse transcriptase polymerase chain reaction (RT-PCR). Results: 309 patients (232 women, 77 men, mean age (SD) 54.1 (14.8) years) were studied. Their mean (SD) disease duration was 74.1 (91) months. Tests for rheumatoid factors and antinuclear antibodies were positive in 213 (69%) and 114 (37%) of the patients respectively. Systemic vasculitis was found in 12 (4%) of the patients. Mean erythrocyte sedimentation rate was 36.4 (SD 30.5) mm at the first hour (normal < 10 mm) and C reactive protein was 36.8 (SD 45.8) mg/l (normal range <5 mg/l), respectively, with 181 (58.6%) of patients considered as having active disease. Aspartate transaminases were increased in 14 (4%) patients, and alkaline phosphatase in 14 (4%). A positive anti-HCV serology was found in two (0.65%) patients, including one with a previously diagnosed HCV infection. HCV RNA was positive by RT-PCR in one of those two patients. Conclusion: A 0.65% prevalence of past or active HCV infection was found in patients with RA, which did not differ from the prevalence of HCV in the general French population. This result does not support the participation of HCV infection in the pathogenesis of RA.