Evaluation of renal arterial blood flow in patients with various stages of schistosomal hepatic fibrosis by duplex ultrasonography

ABSTRACT

Studies of renal perfusion when kidney function tests are still normal could be useful to understand the pathophysiology of renal impairment in schistosomal hepatic fibrosis; currently, this requires invasive methodology. Duplex Doppler ultrasonography allows noninvasive evaluation of intrarenal arterial resistances. In 40 patients with schistosomal hepatic fibrosis [10 with hepatomegaly, 10 with hepatosplenomegaly, 10 with shrunken liver and splenomegaly, and 10 with shrunken liver, splenomegaly and ascites] with normal kidney function [normal serum creatinine and urea levels] and in 20 healthy controls, we measured the intrarenal arterial resistivity index [Resistivity index = [Peak systolic velocity - Minimum diastolic velocity]/Peak systolic velocity] and the pulsatility index [Pulsatility index = [Peak systolic velocity - Minimum diastolic velocity]/ Mean velocity] by Duplex Doppler ultrasonography after visualization of interlobar, interlobular or arcuate arteries by color Doppler ultrasonography. The resistivity index and pulsatility index [calculated as the mean of three to five consecutive determinations] were significantly higher in patients with shrunken liver and splenomegaly than in controls or in patients with hepatomegaly only. Also, these indices were significantly higher in patients with shrunken liver, splenomegaly and ascites than in controls or other patients included in this study. On the basis of these results, Duplex ultrasonography is useful in pathophysiology and clinical studies in such patients