Unusual renal mass in a newborn infant.

A newborn male infant had a right flank mass and hematuria. A solid renal mass was demonstrated on ultrasound and computed tomography studies, while Doppler studies suggested the diagnosis of renal vascular injury. Laparotomy disclosed avulsion of the right renal pedicle, and a right nephrectomy was performed. Traumatic renal hemorrhage should be considered in the differential diagnosis of a solid renal mass in the neonate, especially if the history or physical findings suggest trauma or if there is evidence of abdominal hemorrhage.