LCN2 and proliferative glomerulonephritis: Therefore, higher urinary concentrations of NGAL and KIM-1 in patients with ATN compared with patients with proliferative glomerulonephritis in this study may be attributed to more severe tubular lesion in ATN group, and not to an under-regulated expression of NGAL and KIM-1 in patients with proliferative glomerulonephritis.