The renal resistive index as a new complementary tool to predict microvascular diabetic complications in children and adolescents: a groundbreaking finding

Abstract

The increasing prevalence of type 1 diabetes mellitus (DM) has made it necessary to have new markers for early detection of diabetic nephropathy. Renal resistive index (RI) by using renal Doppler can be a helpful tool in detecting functional alterations in renal hemodynamics. This study was conducted on 100 children and adolescents with type 1 DM. They were further subdivided into two equal subgroups: group 1 with type 1 DM and normo-albuminuria [urinary albumin excretion (UAE) <30 mg/24 hours], and group 2 with type 1 DM and hyper-albuminuria (increased UAE >30 mg/24 hours). There were 37 males (37%) and 63 females (63%); their mean ages were 13.6±2.53 (range, 10-19) years and mean disease duration was 8.867±2.260 (range, 5-13) years. Progressive increase in RI was significantly associated with increased disease duration more than 10 years, elevated serum HbA1c more than 7.5% and early pubertal stages. While not significantly related to sex, weight, height, blood pressure or serum lipid profile, diabetic micro-vascular complications (nephropathy and sensory neuropathy) were more prevalent among patients with RI more than 0.58. Renal RI could be a useful complementary test for the evaluation of functional alterations in renal hemodynamics in the early stages of diabetic nephropathy.

Transabdominal Renal Doppler Ultrasound in Healthy Adult Holstein-Friesian Cows: A Pilot Study

“…In the present study, we suggest an upper cut-off value for the RI of 0.63 and for the PI of 1.00 in healthy Holstein-Friesian cows. Different RI cut-off values have been established in human medicine, ranging from 0.58 [ 19 ] to 0.70 [ 11 ], partly because of variable normal values, which are affected by age and other physiological factors. Ostrowska et al [ 17 ] consider 0.71 and 0.68 as the upper normal limits of RI in interlobar renal arteries in dogs and cats respectively; these values are similar to those suggested by Novellas et al [ 12 ].…”

“…Doppler US of the kidneys provides dynamic information about the renal blood flow associated with renal function [ 10 ] and about how this is modified by different physiological factors and/or pathological conditions [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. It can be used as a guide for renal biopsies to reduce haemorrhage risk [ 7 , 21 , 22 ], by providing information about microvascular and parenchymal lesions [ 10 ].…”

“…Age, sex and body weight (BW) have been studied as potential factors influencing the RI in humans [ 11 , 19 ], dogs [ 20 ], cats [ 9 , 23 ], horses and donkeys [ 24 , 25 ]. Although sex has not been identified as an influential factor in any species, age [ 11 , 20 ] and BW can alter the RI [ 23 ].…”

“…Both RI and PI can be altered even with normal or minimal changes in both the blood renal markers and in the B-mode US, indicating that these indexes are early markers in the disease process, e.g., in diabetic nephropathy [ 10 , 11 , 19 ]. In cattle, urea levels are not always correlated with kidney damage, because of protein and ruminal metabolism [ 6 , 7 ], and therefore a significant amount of tissue damage must occur before the values of the blood parameters increase.…”

Doppler of Renal Segmental Artery Resistive Index in Diabetic Patients

“…A useful parameter for quantifying the changes in renal blood flow that may occur with renal disease is the Doppler Resistive Index ( RI) ([peak systolic velocity-end diastolic velocity] / peak systolic velocity). 15 Originally, RI was introduced to detect peripheral vascular diseases. In the analysis and management of aarteria renalis stenosis and renal graft incompatibility.…”