IgG anti-beta2-glycoprotein I antibodies in adult patients with systemic lupus erythematosus: prevalence and diagnostic value for the antiphospholipid syndrome.
OBJECTIVE
To investigate the prevalence of serum anti-beta2-glycoprotein I (anti-beta2-GPI) antibodies and other antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE). To study their diagnostic value for the antiphospholipid syndrome (APS).


METHODS
Anti-beta2-GPI and IgG anticardiolipin (aCL) were determined in sera from 102 consecutive patients with SLE using ELISA. Serum and plasma tests were also done for lupus anticoagulant (LAC), syphilis, and antibodies to dsDNA. Clinical and laboratory features of APS were observed.


RESULTS
Prevalences were 23.5% for aCL and 18.6% for anti-beta2-GPI. Correlations between the presence of aCL and anti-beta2-GPI and between their titers were statistically significant (p<0.0001). No associations were found between anti-beta2-GPI and disease activity criteria (SLEDAI, ECLAM, dsDNA). Anti-beta2-GPI were significantly associated with LAC (p = 0.005), APS (p = 0.005), and a high aCL titer (aCL > 5 SD; p< or =0.001). LAC was the best diagnostic criterion for APS.


CONCLUSIONS
These data suggest that determination of anti-beta2-GPI in addition to aCL and LAC is unlikely to improve the diagnosis of APS in patients with SLE.
Tubach
F
F
Department of Rheumatology, Bichat Teaching Hospital, University of Paris, France.
Hayem
G
G
Marchand
J L
JL
Weber
M
M
Palazzo
E
E
de Bandt
M
M
Roux
S
S
Kahn
M F
MF
Meyer
O
O
D000293:Adolescent; D000328:Adult; D000368:Aged; D017153:Antibodies, Anticardiolipin / Q000097:blood*; D015415:Biomarkers; D002648:Child; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000453:epidemiology* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D013927:Thrombosis / Q000453:epidemiology / Q000276:immunology; D053482:beta 2-Glycoprotein I
D017153:Antibodies, Anticardiolipin; D015415:Biomarkers; D006023:Glycoproteins; D007074:Immunoglobulin G; D016682:Lupus Coagulation Inhibitor; D053482:beta 2-Glycoprotein I