LCN2 and lupus nephritis: Renal biopsy of the patients with nephritis showed mesangial disease (Class II, 9 cases), focal proliferative glomerulonephritis (Class III, 8 cases), and diffuse proliferative glomerulonephritis (6 cases); in patients with lupus nephritis, all groups of subjects had similar urinary lipocalin-2/creatinine ratios.