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Updated: Jun 16, 2026

Transmesenteric Laparoscopic Pyeloplasty in Trendelenburg Position for Horseshoe Kidney with Hydronephrosis
Published on: July 8, 2025
[MRI evaluation of a supernumerary kidney fused with a horseshoe kidney]
A Nieto Parga1, M Villalón Ortega, J Barceló Obregón
1Servicio de Radiodiagnóstico, Hospital Clínico Universitario, Santiago de Compostela, España. ang.nie.par@gmail.com
Abstract:
We present the case of a patient in whom a horseshoe kidney was discovered during US examination performed for abdominal pain. MRI confirmed this finding and also revealed a supernumerary kidney. The three kidneys were fused, with the supernumerary kidney forming the isthmus of the horseshoe kidney. Whereas horseshoe kidney is a relatively common renal malformation, a supernumerary kidney is one of the rarest renal malformations. The coexistence of these two malformations and especially the particular disposition of the supernumerary kidney is very rare. Knowledge of this malformation is interesting because it can lead to complications such as lithiasis, hydronephrosis, infections, and neoplasms and because it has important implications for surgical planning.
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