DefinePK

Abstract

Background: Routine biomarkers have limited value predicting flares in Systemic Lupus Erythematosus (SLE). Recent evidence suggests that urinary biomarkers, such as Urinary Neutrophil Gelatinase Associated Lipocalin (NGAL), can predict renal relapses, differentiating activity to those with ongoing nephritis.
Objective: To determine if NGAL is useful for evaluating kidney relapse and / or SLE activity, compared to conventional biomarkers.
Methods: Descriptive cross-sectional study. Samples were collected from 66 patients prospectively followed, who fulfilled ≥4 ACR 2012 revised criteria for the classification of SLE. Lupus activity was evaluated by SLEDAI-2K, serum biomarkers were measured: anti-dsDNA and complement by ELISA method; and urinary biomarkers: protein in urine / 24 hours, urinary sediment and NGAL measured by immunochemiluminescence.
Results: Samples from 66 patients, including 64 women (97%) and 2 men (3%) with a mean of 45.7 years, lupus activity was high in 61%. Among these, 6% they met lupus nephritis criteria. The NGAL was altered in 32%; in patients with proteinuria >500 mg/l/24 hrs. and urinary cast the NGAL was elevated in 100% and 75% (p < 0.05); homogeneous and speckled ANA patterns were related to a high NGAL (p <0.05). When evaluating markers of lupus activity, altered anti-dsDNA and complement were related to a high activity (p<0.05); likewise, the NGAL was found to be altered (p<0.05).
Conclusion: In this study, biomarkers were found to be useful to assess lupic activity and renal flares. The use of NGAL shows promise in identifying activity and renal relapse, as well as anti-dsDNA and complement.