FRI0138 Anticardiolipin antibody isotype profile and lupus nephritis severity based on renal biopsy pathology

Abstract

Background Lupus nephritis remains the most prominent organ system manifestation of systemic lupus erythematosus (SLE) and is associated with high morbidity and mortality, particularly in the diffuse proliferative form of the World Health Organisation classification. Evidences have shown that antiphospholipid antibodies may be of pathogenetic significance in lupus nephritis, since glomerular capillary thrombi are an indicator of subsequent renal dysfunction. Objectives To determine anticardiolipin antibody isotype profile in SLE patients with and without lupus nephritis, and the association with lupus nephritis severity based on renal biopsy classification. Methods 200 Chinese SLE patients, followed between Jan. 1991 to May 1996 at Kaohsiung Veterans General Hospital Rheumatology Clinic were included in this study. All patients fulfilled ARA criteria for SLE. Anticardiolipin antibody (aCL) was measured by the ELISA according to international standardised method in 100 SLE patients with lupus nephritis verified by renal biopsy (Group A), 100 SLE patients without lupus nephritis (Group B), and 30 patients with renal biopsy-proved nephropathy not due to SLE (Group C). Renal biopsy morphology was assessed using WHO criteria for the classification of lupus nephritis. aCL isotype profile was analysed in each group and in the subgroups of lupus nephritis patients according to WHO classification. Results Conclusion In this study, the frequency of aCL in our SLE patients was low as compared to previous reports. It may be due to racial difference. From our preliminary data, though not statistically significant, no difference in the frequency of aCL was identified amongst patients with and without lupus nephritis. No correlation between aCL isotype profile and the severity of lupus nephritis could be demonstrated.