Blunt renal trauma in children with pre-existing renal abnormalities.

The kidneys are the most commonly injured genitourinary organ in children following blunt abdominal trauma. Though the retroperitoneal location affords the kidneys some protection from the forces experienced in blunt abdominal trauma, the kidneys are at greater risk of injury when a disease process exposes them from their normal shielded location. In such cases, the injuries may appear to be disproportionate in relation to the severity of the trauma history, confusing the imaging findings. Recognition of both the underlying disease process as well as the manifestations of acute trauma is important; therefore, we present a pictorial essay of traumatized kidneys in children with pre-existing renal abnormalities.