Usefulness of Doppler ultrasound for the early diagnosis of diabetic nephropathy in type 1 diabetes mellitus.

PURPOSE Early diagnosis and management of diabetic nephropathy (DN) might prevent or delay its progression to end-stage renal disease. The purpose of this study was to investigate whether changes in the duplex Doppler resistivity index (RI) are useful for the early identification of renal involvement in children and adolescents with insulin-dependent diabetes mellitus and associated conditions. MATERIALS AND METHODS A total of 49 diabetic patients (two groups: 21 with DN and 28 without DN) were included in this study. DN was defined as 30-300 mg/l of albumin excretion in a random urine sample. The RI of the main renal arteries and their intrarenal branches (arcuate, interlobar) were evaluated with duplex Doppler ultrasound and correlated with age, renal length, duration of diabetes, and laboratory examinations. RESULTS The mean age did not significantly differ between the two groups. The patients with DN had a significantly longer duration of type 1 diabetes (p = 0.02). The majority of patients (90.5%) had mild renal involvement with microalbuminuria and normal renal function. The mean RI was normal in both groups of patients, with no significant difference between the two groups. CONCLUSION The RI did not increase in the early clinical stage of DN and was not a reliable marker for the screening of DN in patients with type 1 diabetes mellitus.