Objective: To investigate the occurrence of herpesviruses, including Epstein-Barr virus (EBV), herpes simplex viruses types 1 and 2 (HSV-1; HSV-2), and human herpesvirus 6 (HHV-6), in lymphocytes from patients with rheumatoid arthritis (RA) of less than 1 year's duration.
Methods: The polymerase chain reaction was applied to cells isolated from synovial fluid and peripheral blood. Indirect immunofluorescence and enzyme immunoassay techniques were used to detect antibodies against EBV and HSV, respectively.
Results: EBV DNA was present in synovial fluid lymphocytes from 19% (7 of 37) of the RA patients and 33% (5 of 15) of the patients with reactive arthritis (ReA). Peripheral blood lymphocytes harbored EBV DNA in 39% of the RA patients, 39% of the ReA patients, 27% of the patients with other arthropathies, and in 31% of the healthy control subjects. HSV-1, HSV-2, and HHV-6 viral DNA was not detected in cells from the synovial fluid or peripheral blood.
Conclusion: Our findings do not support the participation of EBV, HSV-1, HSV-2, or HHV-6 in the pathogenesis of RA. A role for the highly prevalent EBV cannot be excluded, however, since potential contributions may become manifest only when other necessary factors are involved. RA pathogenesis caused by an overproduction of the EBV virus is nevertheless highly unlikely.