Detection of cytomegalovirus, Epstein-Barr virus and herpes virus-6 in patients with rheumatoid arthritis with or without Sjögren's syndrome.

The frequency of latent viral infection by cytomegalovirus (CMV), Epstein-Barr virus (EBV) and herpes virus-6 (HHV-6) was investigated in patients with RA with or without Sjögren's syndrome (SS) and in normal controls. Virus presence was determined by polymerase chain amplification of DNA isolated from peripheral blood mononuclear or polymorphonuclear cells and/or saliva-derived mononuclear/epithelial cells. Anti-viral antibodies and autoantibodies were also assayed. Patients with RA both with and without SS were found to have a significantly increased frequency of latent viral infection (two-fold higher, P = 0.035 for EBV and seven-fold higher, P = 0.018 for HHV-6) compared to normal controls but only in cells isolated from saliva. The increased frequency of virally infected cells from the saliva of patients with RA, regardless of the SS status, when compared to normal controls may reflect the ongoing inflammatory process, the impact of therapy and/or a less effective local immune responsiveness.