ABSTRACT
BACKGROUND: Renal involvement was thought to occur more than 10 years after onset of diabetes, but recent studies provide evidence that it starts even in the pre-diabetes stage. However, there is no sensitive marker to detect these changes at such early stages. Novel urinary biomarkers have showed promising results in detection of early nephropathy in pre-diabetics. METHODS: A total of 91 subjects (diabetes 61 and pre-diabetes 30) were enrolled into the study. Urinary biomarkers such as urine Neutrophil Gelatinase-Associated Lipocalin (NGAL), urine Cystatin C and urine albumin-creatinine ratio (UACR) were estimated. Subjects were further divided in four groups on the basis of UACR: pre-diabetes with normoalbuminuria (21); pre-diabetes with microalbuminuria (9); diabetes with normoalbuminuria (37); and diabetes with microalbuminuria (24). The relationship of UACR, NGAL, and Cystatin C was estimated. RESULTS: Urine levels of NGAL and Cystatin C were significantly higher in microalbuminuria group compared to normoalbuminuria. UACR was positively correlated to urine NGAL-creatinine ratio (UNCR) and urine Cystatin C-creatinine ratio (UCCR) in both diabetes and pre-diabetes. On logistic regression odds ratio of UNCR to predict microalbuminuria in diabetes and pre-diabetes was 1.070 (p = 0.000) and 1.138 (p = 0.010), respectively. Area under curve was determined by ROC analysis, and UNCR was found to be better than UCCR for estimating microalbuminuria. CONCLUSION: Tubular damage may play major role in development of nephropathy in pre-diabetes. Newer markers like urine NGAL and Cystatin C are raised early in diabetes and pre-diabetes nephropathy.
