Urinary NGAL levels were found to be markedly elevated in patients with diabetes when compared with nondiabetic control subjects [14, 21–27] and to correlate negatively with eGFR and positively with serum Cystatin C (CysC), serum creatinine (SCr), proteinuria, albuminuria, and urinary albumin excretion (UAE) and albumin-creatinine ratio (UACR), indicating the possible clinical application of urinary NGAL as a complementary marker for early detection of DN [19, 25–29]. This evidence concerns the gene LCN2 and diabetes mellitus.