PO.5.103 Study of b cells in patients with lupus nephritis: parameters of disease activity and remission

PurposeB cells play a pivotal role in systemic lupus erythematosus (SLE) pathogenesis. The aim of this study was to investigate the relationship between peripheral blood B cell phenotype, disease activity and histological lesions in lupus nephritis (LN-SLE).MethodsOne hundred LN-SLE with active renal involvement, 40 at disease diagnosis (Early) and 60 in whom LN occurred after the disease diagnosis (Long) were enrolled, 37 controls were included. Clinical, laboratory and demographic data were collected at baseline and after 6 and 12 months. Disease activity was recorded using SLEDAI-2K. Nephritic class was evaluated according to the ISN/RPS classification. Memory B cells immunophenotyping (IgD/CD27 classification) was analyzed in peripheral blood through flow cytometry. IL-6 and BAFF serum levels were assayed by ELISA.ResultsThere were no differences in the distribution of the renal classes and in activity and chronicity indices in the Early and Long groups. A direct correlation was observed between chronicity index score and creatinine in the whole cohort (R=0.342;p