Crossed nonfused renal ectopia with variant blood vessels: a rare congenital renal anomaly

Crossed renal ectopia is a rare congenital anomaly, where one of the kidneys crosses the midline and lies opposite to the site of its normal ureteral insertion. Ninety percent of crossed ectopic kidneys are fused to their ipsilateral uncrossed kidney. Crossed renal ectopia without fusion is rare. We present the case of a 53-year-old male with an unusual incidental finding of crossed nonfused renal ectopia, with the left ectopic kidney lying anterior to the right kidney without fusion. The ectopic kidney had dual arterial supply: one from the aorta and another from the right renal artery. It also demonstrated dual venous drainage; a main left renal vein and an accessory renal vein. The main left renal vein joined the right renal vein to form a common renal vein before draining into the inferior vena cava. The accessory renal vein joined the left testicular and left lumbar veins to drain into the inferior vena cava. Multiple bilateral nonobstructing renal calculi were also noted. Although the patient was asymptomatic, the authors highlight potential complications related to the above-mentioned condition and the importance of identification of the findings.