Diagnostic value of antiagalactosyl IgG antibodies in rheumatoid arthritis.
Our objective in this study was to explore the diagnostic value of antiagalactosyl IgG antibodies in rheumatoid arthritis (RA). The study comprised 266 Japanese patients with systemic autoimmune diseases, including 60 with RA. Human agalactosyl IgG was prepared enzymatically, and the serum levels of antiagalactosyl IgG antibodies were determined using a lectin enzyme immunoassay. Serum IgG and IgM rheumatoid factors (RF) were measured using laser nephelometry for IgM (LN-RF) and an enzyme-linked immunosorbent assay for IgG (IgG-RF). Antiagalactosyl IgG antibodies were significantly more common in patients with RA than in those without (78% vs. 18%, odds ratio (OR) 16.51, 95% confidence interval (CI) 8.12-33.58, p<0.0001). Patients with RA also had a higher frequency of LN-RF than those without RA (75% vs. 28%, OR 7.81, 95% CI 3.91-15.58, p< 0.001). The specificity of antiagalactosyl IgG antibodies for RA was significantly higher than that of LN-RF (82% vs. 72%, p<0.0011). There was a significant correlation between titers of antiagalactosyl IgG antibodies and C-reactive protein levels. Antiagalactosyl IgG antibodies are more specific markers for RA than conventional LN-RF, and may provide useful information for the diagnosis of RA.
Das
Hemlata
H
Department of Medicine II, Hokkaido University Graduate School of Medicine, N15 W7, Kitaku, 060-8638 Sapporo, Japan.
Atsumi
Tatsuya
T
Fukushima
Yukari
Y
Shibuya
Hitoshi
H
Ito
Keiko
K
Yamada
Yuji
Y
Amasaki
Yoshiharu
Y
Ichikawa
Kenji
K
Amengual
Olga
O
Koike
Takao
T
D000906:Antibodies / Q000097:blood / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis* / Q000276:immunology*; D001327:Autoimmune Diseases / Q000097:blood / Q000175:diagnosis / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology; D012189:Retrospective Studies; D012217:Rheumatoid Factor / Q000097:blood / Q000276:immunology; D012680:Sensitivity and Specificity
D000906:Antibodies; D007074:Immunoglobulin G; C064155:agalactosyl IGG; D012217:Rheumatoid Factor