RESUMO
In thirty subjects with different renal disorders classified into three groups each group contains 10 subjects; nephritis group, renal colic group, and chronic renal failure group; and 10 subjects as healthy control group. Study of renal arterial blood flow and its relation to kidney functions in these renal disorders using Duplex-Doppler ultrasonography was done. The end diastolic flow [D] and the early peak systolic flow [S], the resistive index [RI], the pulsatility index [PI] and the D/S ratio were recorded. All the doppler indices were nearly the same as normal in the nephritis group. Resistive index values were significantly increased [P < 0.01] in the renal colic and chronic renal failure group, resistive index of 0.70 was considered the upper limit for normal kidneys. The D/S ratio was significantly decreased [P < 0.05] in renal colic and renal failure groups D/S ratio of 0.30 has considered the minimum value/or normal kidneys. Both chronic renal failure and renal colic increase the renal peripheral resistance but glomerulonephritis did not alter it, so all the doppler indices remain unchanged as long as the disease remain limited to the glomeruli. A significant correlation exists between blood urea and D/S ratio [r = 0.69], as well as between serum creatinine and D/S ratio [r = 0.75] in chronic renal failure group. In conclusion, there is an altered blood flow in renal obstruction and chronic renal failure. While no change in renal arterial blood flow in diseases limited to glomeruli. Duplex Doppler ultrasonography is a good non-invasive method for evaluation of renal functions from the pattern of renal arterial blood flow, however it can not differentiate between healthy subjects and glomerulonephritis or between renal obstruction and chronic renal failure