Although current therapeutic decisions in LN are guided by its histological classification,20 21 45 kidney histology is an imperfect predictor of kidney outcome,1 highlighting the need for improved biomarkers.44 The urokinase-type plasminogen activator receptor and the decrease in urinary epidermal growth factor to creatine ratio have been identified as independent predictors of progression to chronic kidney disease in patients with glomerular diseases46 47; however, a biomarker for preclinical LN has not been identified. This evidence concerns the gene EGF and chronic kidney disease.