Urine neutrophil gelatinase-associated lipocalin as an early biochemical marker of microalbuminuria in predicting early kidney damage in patients with type 2 diabetes mellitus

Diabetic nephropathy is one of the microvascular complications of diabetes mellitus. The study was done to evaluate the diagnostic value of neutrophil gelatinase-associated lipocalin (NGAL) urine level as a biomarker for the early detection of nephropathy in type 2 diabetic patients. This study was performed on 150 patients with type 2 diabetes mellitus classified into three equal groups according to their urine albumin/creatinine ratio (ACR), including patients with normoalbuminuria (ACR < 30 mg/g creatinine), microalbuminuria (ACR = 30–300 mg/g creatinine) and macroalbuminuria (ACR > 300 mg/g creatinine). Fifty apparently healthy subjects were selected as a control group. Urine NGAL was estimated by a particle-enhanced turbidimetric immunoassay using Hitachi 917 analyzer. The serum level of glucose and creatinine was also estimated. The results showed that NGAL urine level was significantly elevated in diabetes patient groups with microalbuminuria and macroalbuminuria when compared to the control group and diabetes patient group with normoalbuminuria. The levels of urine NGAL correlated positively with microalbuminuria in patients with diabetes. Receiver operating characteristic curves revealed that urine NGAL had a higher diagnostic value for diabetic nephropathy early detection compared to ACR and microalbuminuria in patients with diabetes mellitus.