ABSTRACT
Introduction: Antiphospholipid Antibodies (APA) are detected in 30 and 40% of patients with Systemic lupus erythematosus (SLE). Antiphospholipid Syndrome nephropathy (APSN) is one of renal manifestations of APS. Histological lesions of APSN have been described in SLE. Objective: To evaluate the prevalence of APA in patients with lupus nephritis (LN), its clinical and laboratory association and the presence of APSN in renal biopsies from LN patients. Patients and Methods: We retrospectively studied 28 patients with SLE diagnosis according to ACR criteria, who underwent renal biopsies with diagnosis of LN. These patients attended to our rheumatology unit for the last 2 years. Demographic, clinical and serological data were collected at the time of the first biopsy. APA (Anticardiolipin Ig G, Ig M and lupus anticoagulant) were considered positivewhen they were positive in two opportunities during the follow up. Renal biopsies were classified according to NL classification 2004. Histological features of APSN were analyzed by 2 different pathologists who were blind to clinical data. P value <0.05 was considered statistically significant. Results: Mean age was 31 years old (17-53), 86% were female and mean SLE duration was 47 months (1-180). 54% of patients were positive for APA. There was not association between APA and first creatinine level, hypertension, amount of proteinuria and active sediment. Class II LN was most frequently associated with APA. Glomerular collapse and focal cortical atrophy (FCA) were associatedwith APA (p<0.008, p<0.005). Conclusions: APA were present in 54% of patients with LN. There was not association between APA and clinical features or histological type of LN. The main histological features of APSN were glomerular collapse and FCA