Value of renal resistive index as an early marker of diabetic nephropathy in children with type-1 diabetes mellitus

Constant increase in the incidence of type-1 diabetes (T1-DM) has made it necessary to have new markers for the early detection of diabetic nephropathy (DN). One of the markers that could be helpful in detecting functional alterations in renal hemodynamics is assessment of the renal resistive index (RI) by using renal Doppler. We studied 25 patients with T1-DM (Group-A), which comprised of 15 females and 10 males, with a mean age of 10.8 +/- 2.2 years and duration of diabetes of 5 +/- 1.1 years. A control group (Group-B) comprising 20 healthy children, 12 females and eight males with mean age of 11.6 +/- 2 years, was also studied. The following parameters were studied in the two groups: age, serum creatinine, albumin excretion rate (AER), glomerular filtration rate (GFR), glycosylated hemoglobin (HbA1c) and mean renal RI of both kidneys. We found an increase in the mean RI in diabetic patients versus healthy children; the mean RI in Group-A was 0.64 +/- 0.55 while it was 0.58 +/- 0.0.28 in Group-B (P <0.000). This increase in RI had a positive correlation with duration of the disease, GFR and HbA1c levels, but there was no correlation with serum creatinine or AER. We conclude that RI is increased early in TI-DM, and it can be a predictor of DN.