To determine the prevalence of GB virus-C (GBV-C) RNA and TT virus (TTV) DNA in patients with systemic sclerosis (SSc), rheumatoid arthritis (RA), and osteoarthritis (OA) as well as to compare the autoantibody pattern in patients with SSc with and without evidence of viral infection.
The study included 168 patients (84 SSc, 41 RA, and 43 OA) diagnosed according to the American College of Rheumatology criteria and 122 volunteer blood donors. The presence of GBV-C RNA and TTV DNA in serum was assessed by nested reverse transcriptase-polymerase chain reaction (RT-PCR) and semi-nested PCR, respectively. Autoantibodies in patients with SSc were determined by enzyme linked immunosorbent assay (ELISA) and Hep-2 immunofluorescence.
TTV-DNA was detected in 10/84 (12%) patients with SSc, 9/41 (22%) patients with RA, 3/43 (7%) patients with OA, and 16/122 (13%) blood donors. GBV-C RNA was present in 4/84 (5%) patients with SSc, 2/43 (5%) patients with OA, and 5/122 (4%) blood donors. No patient with RA was positive for GBV-C RNA. One patient with SSc and one patient with OA showed a double infection with GBV-C and TTV. 74/84 (88%) patients with SSc were positive for at least one autoantibody species tested: 18/84 (21%) showed anticentromeric autoantibodies, 55/84 (66%) a speckled (36/84 (43%) fine, 19/84 (23%) coarse), and 20/84 (24%) a homogeneous nuclear Hep-2 pattern, and 21/84 (25%) had antinucleolar autoantibodies. Anti-Scl-70 antibodies were found in 31/84 (37%) and anti-RNP antibodies in 5/84 (6%) patients with SSc. No differences in the autoantibody pattern in patients with SSc with or without viral infection could be detected.
The prevalence of GBV-C RNA and TTV DNA in serum samples from patients with SSc, RA, and OA was low and comparable with that in blood donors. A continuing infection with TTV and or GBV-C was not associated with a significant change in the autoantibody pattern in patients with SSc. These data provide no evidence for an association between GBV-C and/or TTV infections and SSc and/or arthritis (RA and OA).