an unusual case of crossed-fused renal ectopia

Crossed-fused renal ectopia (cfre) is a rare congenital anomaly in which both kidneys lie on the same side of the spine while retaining separate ureteric insertions into the bladder. because most individuals remain asymptomatic, cfre is usually typically detected incidentally or when evaluating complications such as infection or calculi. we describe a 63-year-old woman who presented with flank discomfort and dysuria secondary to a urinary tract infection (uti). imaging revealed right-to-left cfre and a 20 × 27 mm calculus in the left renal pelvis. a staged strategy consisting of broad-spectrum antibiotics, bilateral double-j stenting, and flexible retrograde intrarenal surgery achieved complete stone clearance. the patient was symptom-free at 1-month follow-up. this report highlights the diagnostic value of cross-sectional imaging and demonstrates that minimally invasive endourological techniques can be safely employed in cfre.