Changes of renal flow volume in the hemolytic-uremic syndrome - color Doppler sonographic investigations

Abstract

Varying degrees of vascular occlusion can be found in the hemolytic-uremic syndrome (HUS). This is the rationale for Doppler sonographic investigations of renal blood flow in children with HUS. In 1989 a first report suggested a close relationship between normalization of the resistive index (RI) of renal blood flow with the restitution of urine flow in affected children. Later reports did not confirm these initial findings. The aim of this paper is to describe renal volume perfusion quantitatively in children with HUS. The renal arteries in 35 patients with HUS (1 month to 15 years) were investigated at the onset of HUS by color Doppler ultrasonography. Flow volume measurements were carried out in the 1st week and in the 2nd to 4th week after onset of the disease. These data were compared with measurements from a healthy pediatric population of 69 children. Statistically significant changes in renal perfusion occur in the flow volume of the kidneys. The flow volume dropped to 32% (34%) in the 1st week of the disease compared with the normal population and recovered in 2-4 weeks to 117% (65%) of the normal flow volume (left kidney in parentheses). The new technique of volumetric perfusion measurement overcomes some drawbacks of the traditional RI, which may have led to some confusion in the past.

Dynamic Tissue Perfusion Measurement: A Novel Tool in Follow-Up of Renal Transplants

“…Measurements of peripheral vessel distance to renal surface and percentage of vascularization (compared with the entire parenchymal area) have been proposed to describe the extent and intensity of perfusion more comprehensively and in a tissue-related fashion (6). RI and PI are single-vessel parameters (7,8) and suffer from the fact that, in decreased perfusion, only those vessels can be interrogated that are visible. This might lead to an erroneous favorable impression, because badly perfused vessels are not detectable (9).…”

Renal Relevant Radiology

“…In pediatric hemolytic-uremic syndrome, ultrasonography demonstrates enlarged kidneys with hyperechoic cortex, increased corticomedullary differentiation, increased RI, and frequent reversal of diastolic flow (48,49). It has been suggested that normalization of flow as assessed by RI or flow volume may predict renal recovery (50).…”

Compensatory renal growth protects mice against Shiga toxin 2-induced toxicity

“…Renographic studies revealed that Stx2 provoked a severe drop in the blood flow of the kidney, which agrees with Stx-induced renal alterations comprising ischemic injury and varying degrees of vascular occlusion found both in humans [40] and in mice [21]. The increase in renal perfusion during CRG was able to counterbalance the ischemic effect of Stx2.…”