Crossed renal ectopia with fusion in a female feline: case report

Abstract

A 3 year old female feline of mixed breed was sent to the diagnostic imaging sector under suspicion of bleeding due to ovariohysterectomy. An abdominal ultrasonography was performed to confirm the initial suspicion. However, no signs of bleeding were found, instead it was observed that the left renal silhouette had two pelvises and was elongated and larger than normal. The right kidney was not found. Excretory urography was requested to evaluate the condition of the ureters. The final diagnosis was crossed renal ectopia with fusion in an asymptomatic cat with no changes in renal function.

Crossed renal ectopia with fusion in a pelvic inlet area, atypical portal vein and coccygeal deformation in a young female cat

“…In crossed ectopia with fusion, the migration of the left kidney to the right side is most often described in humans [3]. In the cases of CFRE reported to date in cats, the kidney fusion consisted in moving one of them to the contralateral one, located physiologically [3,9,10]. In the present case, both kidneys were ectopic, in addition a fusion and changes in the sides of the renal pelvis were observed.…”

“…Ectopic kidneys have previously been described as a defect in humans [ 6 ], cattle [ 7 ], dogs [ 2 , 8 ] and cats [ 3 – 5 , 9 , 10 ], most often as asymptomatic and appearing rarely. Until now, CFRE cases in cats were reported in both, males [ 3 , 9 ] and females [ 4 , 5 , 10 ]. Developmental defects, especially CFRE, may predispose to the occurrence of nephrolithiasis, hydronephrosis or urinary tract infections resulting in pyelonephritis [ 3 ].…”

“…To date, five reports of CFRE in cats have been described [ 3 – 5 , 9 , 10 ]. Modern methods of diagnostic imaging allow for better detection of this type of congenital defects in vivo, and reports describing the condition can be extremely helpful in the differential diagnosis of the masses in the caudal part of the abdominal cavity [ 3 ].…”

Imaging features of renal ectopia and fusion in 13 cats

“…7 For the four published cases, two cases were in male cats and two cases were in female cats. [9][10][11][12] In this series, 9/13 cases were in male cats and 4/13 were female cats. These results are consistent with this anomaly being reported to occur more commonly in males vs females.…”

“…There are a few case reports describing CFRE in cats, but no specific classification system pertaining to CFRE exists for cats. 9 – 12 The published data show that this condition has occurred in both male and female cats of varying ages and breeds. The left and right kidneys have been documented to cross the midline and fuse to the contralateral kidney.…”