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 Tc-99m-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 Tc-99m-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.