REN and diabetes mellitus: It is also significantly correlated with the duration of diabetes, glycemic control (HbA1c), and urinary interleukin-18 (IL-18: proinflammatory biomarker) and angiotensinogen (renin-angiotensin system biomarker), suggesting urinary NGAL as a useful noninvasive tool for the evaluation of renal involvement in diabetes [21, 23, 25, 28, 29].