Crossed Fused Renal Ectopia with Single Ureter and Single Renal Vein: A Rare Case

Abstract

Crossed fused renal ectopia with a single ureter and single renal vein is a rare congenital anomaly in which both the fused kidneys lie on one side of the body. We present an unusual case of crossed fused renal ectopia with a single ureter, single renal vein, and a calculus in a 22-year-old man who presented with lower abdominal pain, burning micturition, and a right-side abdominal lump present for three months. On abdominal ultrasound and non-contrast computed tomography (CT), the left kidney was not visualized in the left renal fossa. However, we noted it on the right side, fused to the lower pole of the right kidney with a calculus within the pelvis leading to mild hydronephrosis. After intravenous administration of non-ionic contrast medium, we saw a single ureter draining both the moieties into the urinary bladder on the right side. A three-dimensional volume rendering technique revealed a single renal vein draining the renal parenchyma into the inferior vena cava. Cross fused renal ectopia is an uncommon congenital anomaly which remains asymptomatic throughout life and undetected in the absence of renal pathologies. Multi-detector computed tomography (MDCT) is an excellent tool for denoting anatomical details of this anomaly; the information provided by MDCT is crucial for surgeons, nephrologists, and radiologists alike in facilitating proper management of the condition.

A case of solitary kidney with duplex collecting systems and renal vascular variants in an adult male cadaver

“…An alternative explanation for this morphology is cross-fused renal ectopia (CFRE) with a single ureter. This phenomenon that has been described elsewhere in various contexts [8,9,12]; however, these reports exhibited characteristics not seen in our case, namely "pancake morphology", anterior orientation of the renal pelves, and atypical location of the renal mass. The presence of multiple renal vessels is also common in cross-fused renal ectopia [11,16,17,18], with many cases reporting atypical origins of the renal arteries, such as the common iliac artery [7].…”

Crossed fused renal ectopia (pancake type) with single ureter: A case report

“…Most PKs are diagnosed incidentally with only few patients developing symptoms like lower abdominal pain and hematuria. 2 Our patient had urosepsis and acute kidney injury. The hydronephrosis was attributed to a possible primary ureteropelvic junction obstruction (UPJO) and/or ureteral angulation due to its distorted path.…”

Imaging features of renal ectopia and fusion in 13 cats

“…6,18 Few human cases have been documented detailing CFRE with either a single renal ureter or vessel and only a single case detailing both a single ureter and renal vein. 19 One case in this series was classified as a horseshoe kidney on CT. Unfortunately, there were no US images available for review for this case.…”

“… 6 , 18 Few human cases have been documented detailing CFRE with either a single renal ureter or vessel and only a single case detailing both a single ureter and renal vein. 19 …”