Relation between hyper-uricemia and renal resistivity index in non diabetic non hypertensive patients

BackgroundRelationship between uric acid and renal artery resistive index (RRI) in hypertensive subjects was recently suggested.AimThe aim was to evaluate the effect of hyper-uricemia on RRI in adult Egyptian subjects with no other risk factors of renal vascular disease, and to assess the impact of therapeutic control of serum uric acid on the RRI.Patients and methods50 adult hyper-uricemic subjects were included in this study, who underwent abdominal ultrasound with Doppler examination of the kidneys. The RI was automatically calculated by the US equipment. Intra-renal resistance was measured at inter-lobar arteries three times in different regions of each kidney (upper, middle, and lower zones) and the mean RI value was calculated. Each case had its pre and post 3 and 6 weeks treatment duplex measurement of RI together with uric acid measurement and correlation.ResultsMean value of the baseline RI was 0.768 ± 0.01355 SD, and mean serum uric acid value was 10.86 ± 0.65 SD, with a positive significant correlation between both values. Mean value of the difference of the serum uric acid level and RRI prior to and 3 weeks after treatment was 2.68 ± 0.49, 0.04 ± 0.01 respectively, with positive significant correlation between the two values p-value: 0.001. Mean value of the difference of the serum uric acid level and RRI 3 and 6 weeks after treatment was 2.18 ± 0.5 and 0.06 ± 0.01 respectively, with significant positive correlation between the two values and p-value 0.00. Mean value of the total change of serum uric acid and RRI over the treatment period was: 2.38 ± 0.43 and 0.049 ± 0.01 with positive significant correlation between the two values and p-value: 0.00.ConclusionSerum uric acid significantly correlates with RRI in the absence of other risk factors affecting renal vasculature. Improvement of serum uric acid is accompanied by the improvement in RRI.