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Transplanted Kidney

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Imaging in Nephrology

Abstract

Kidney transplantation is the treatment of choice for end-stage renal disease, allowing a better quality of life and a greater survival than dialysis. Recent innovations in transplant surgery and the use of novel immunosuppressive drugs have significantly improved graft outcomes; however part of the transplanted graft still develops acute and chronic dysfunction due to infective, toxic, vascular, and/or immune-mediated damage. Although ultrasonography represents the imaging technique of choice for native kidney diseases, its diagnostic role is not fully understood in case of parenchymal and vascular complications of the graft. Color Doppler ultrasound has demonstrated low diagnostic accuracy in the detection of acute parenchymal complications, whereas its specificity is very important in case of stenosis of the transplanted renal artery, pseudoaneurysms, arteriovenous fistulas, and thrombosis. For chronic complications, a meticulous follow-up through measurements of resistance indices repeated over time seems to be more effective than single determinations in improving renal graft outcomes. Modern techniques, including tissue pulsatility index, maximal fractional area, and contrast-enhanced ultrasound (CEUS), are promising tools that will help increase the diagnostic power of ultrasound in case of both parenchymal and vascular complications of the kidney allograft.

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Dugo, M., Maccarrone, R., Campo, I., Pesce, F., Di Lullo, L., Granata, A. (2021). Transplanted Kidney. In: Granata, A., Bertolotto, M. (eds) Imaging in Nephrology. Springer, Cham. https://doi.org/10.1007/978-3-030-60794-4_16

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