OBJECTIVES: The aim of this study was to determine the applicability of Power Doppler ultrasound in the identification of changes in perfusion of renal transplants and their correlation with renal functional reserve and microalbuminuria before and after the infusion of intravenous amino acids. METHODS: Twenty-three renal transplanted patients were assessed by Power Doppler before (baseline), 120 minutes (stage 1) and 240 minutes (stage 2) after the infusion of intravenous amino acids. At the same time, during the three stages, we measured serum creatinine, index of glomerular filtration, renal functional reserve, and microalbuminuria. RESULTS: According to predefined patterns of perfusion by Power Doppler, described by Hoyer et al. in 1999, the patients were divided into three groups: 12 patients with score I, six with score II, and five with score III of renal perfusion. In the renal grafts with an excellent perfusion (score I), there was a significant variation of the variables in stages 1 and 2 (P CONCLUSIONS: The findings suggest that the transplants with perfusion score I have renal functional reserve when stimulated with amino acids. Nevertheless, with the progressive reduction in renal perfusion by Power Doppler, there is a loss in the ability of transplanted kidneys to increase the index of glomerular filtration in response to external stimuli, resulting in absence of renal functional reserve. This study allows for the further understanding of the dynamic evolution of the process of renal function loss in renal transplanted patients.
Power Doppler; renal perfusion; renal transplant
