High seroprevalence of human herpesvirus 8 infection in patients with systemic lupus erythematosus

Abstract

Systemic lupus erythematosus (SLE) is an autoimmune disease that is associated with genetic and environmental factors and microbial infection. With respect to microbial infection, the Epstein-Barr virus (EBV) has been a widely discussed issue in recent decades. Human herpesvirus 8 (HHV-8) belongs to the same γ-herpesvirus subfamily as EBV and is closely related to it. Until now, only one paper has reported the prevalence of HHV-8 infection in SLE patients. The goal of this study was to detect the prevalence of HHV-8 infection in SLE patients to elucidate the relationship between HHV-8 and SLE. We assessed the seroprevalence of HHV-8 in SLE patients by immunofluorescence assay. In addition, we quantified the HHV-8 DNA in peripheral blood mononuclear cells (PBMCs) from SLE patients by real-time polymerase chain reaction (PCR). The prevalence of HHV-8 antibodies in SLE and normal controls was 57.8% (26/45) and 19.2% (5/26), respectively. These data were highly significant (P = 0.001). No HHV-8 DNA was detected by real-time PCR in SLE patients' PBMCs. In addition, we analyzed the prevalence of HHV-8 infection in patients with rheumatoid arthritis and ankylosing spondylitis. There was no significant difference between the patients and normal controls. A high seroprevalence of HHV-8 infection was found in patients with SLE. The negative DNA load and high seropositive rate indicate that most patients might have latent infection.