[Echographic aspects of fused kidneys. Apropos of 2 cases].

Coalescent kidney is a rare variety of fused kidneys, clinical manifestations observed with the greatest frequency being a more or less painful abdominal mass, digestive disturbances and a complicating infection, calculus, renal failure or hematuria. Straight abdominal films (SAF), ultrasound tomography, SAF after colon insufflation and IVU can usually establish the diagnosis. Results of ultrasound imaging of this rare variety of ectopic kidney have apparently not been published. Apart from any complicating factor, the coalescent kidney corresponds to a discoid shaped subumbilical prespinal mass of oblong section. It appears as two highly echogenic central zones encircled by a less dense zone. No separation exists between the right and left portion, and furthermore a kidney cannot be identified in either lumbar fossa. These findings are useful for identification of a retroperitoneal mass, ultrasound imaging being of importance when IVU supplies insufficient data.