# Use of renal contrast-enhanced ultrasound to explore renal cortical microcirculation abnormalities in pediatric acute kidney injury

## TL;DR

This study uses contrast-enhanced ultrasound to examine blood flow patterns in children with acute kidney injury, revealing how drug-induced kidney damage affects kidney microcirculation.

## Contribution

The study introduces a novel approach to analyzing renal microcirculation in pediatric acute kidney injury using contrast-enhanced ultrasound and quantitative perfusion curves.

## Key findings

- Drug overdose caused poor cortical blood flow and prolonged perfusion times in both kidneys.
- Intentional drug use led to delayed wash-out/excretion despite good initial perfusion.
- Glomerular structure and function influence perfusion curve dynamics, offering insights into microcirculation.

## Abstract

To explore the correlation between the quantitative analysis curve of renal contrast-enhanced ultrasound and the anatomical location of renal cortical microcirculation associated with acute kidney injury.

This study included a 1-year-and-11-month-old female child with acute kidney injury caused by drug overdosed and a 14-year-old female child with acute kidney injury caused by drug intentional, who were treated at Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University School of Medicine. Both patients underwent renal contrast-enhanced ultrasound and quantitative analysis. In addition, their clinical medical history data were recorded.

The first child developed acute kidney injury owing to cyclosporine A overdosed. Contrast-enhanced ultrasound revealed poor cortical blood flow perfusion in both kidneys, with abnormally prolonged cortical perfusion times and possible obstruction of vascular inflow pathways. The second child experienced acute kidney injury owing to ibuprofen intentional. Contrast-enhanced ultrasound showed good cortical blood wash-in/perfusion but significantly delayed wash-out/excretion.

The structure and function of the glomerulus significantly influence the perfusion rate and intensity of the rising branch of the curve. Furthermore, the descending branch of the curve is affected by the interplay of the capillaries surrounding the renal tubules. Exploration of these anatomical structures aids in understanding the renal microcirculation pathways and provides further insight into renal perfusion dynamics.