THE CLINICAL AND IMMUNOLOGICAL SIGNIFICANCE OF ANTIPHOSPHOLIPID ANTIBODIES IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

PV018 / #802 Poster Topic: AS03 - Antiphospholipid Syndrome Background/Purpose Systemic lupus erythematosus (SLE) is an autoimmune systemic disease characterized by the presence of the variety of autoantibodies. Antiphospholipid antibodies (APL) are new criteria for classifying lupus disease and their positivity often indicates the association with secondary antiphospholipid syndrome (APS). The aim of the study was to evaluate the frequency, the clinical and immunological associations of antiphospholipid antibodies in patients with SLE. Methods Our study included 156 patients diagnosed and followed up for lupus. The APL were detected by an immuno-enzyme technique (ELISA). Results In our study, 19% of patients (N=29) had 1 of the positive APL. Anti cardiolipines antibodies (aCL) were present in 12% (n=18), while anti-β2GP1 antibodies were positive in 13% of patients (n=20). The frequencies of both IgG and IgM isotypes of aCL and anti β2GP1 were 5%, 7%, 4% and 10% respectively. The study of clinical and immunological associations revealed a positive association between the presence of anti-β2GP1 and neurological involvement (25% vs 7%, P = 0.020, OR=4.70), and between anti-β2GP1 and lupus nephritis (45% vs 68%, P = 0.044, OR=0.39). Moreover, a significant association was observed between the presence of aCL and hypocomplementemia of C3 and C4 fractions (P=0.012, OR=3.48). Conclusions APL positivity is quite common in SLE patients. Their presence should suggest a possible association with secondary APS and monitoring of patients for thrombotic risk or obstetric complications.