A rare case of a pediatric patient affected by crossed fused renal ectopia: the usefulness of dual tracer99mTc-diethylenetriamine pentaacetic acid/99mTc-dimercaptosuccinic acid scintigraphy

A 9-year-old male patient, with an ultrasonography diagnosis of horseshoe kidney condition, was referred to our hospital for recurrent urinary tract infection. He was submitted to 99mTc-diethylenetriamine pentaacetic acid sequential scintigraphy that demonstrated urine stasis in the calyces of both kidneys and was also suggestive for 8-shaped right-to-left crossed-fused renal ectopia. A subsequently performed 99mTc-dimercaptosuccinic acid scan confirmed the diagnosis of crossed renal ectopia, also disclosing, through single-photon emission computed tomography (SPECT) acquisition, cortical uptake defects in both kidneys, and indicative of renal scarring due to recurrent pyelonephritis. Combined scintigraphy and appropriate technological approaches (SPECT/3D volume rendering) may be useful in selected patients with congenital anomalies