Renal duplication and fusion anomalies.

Renal duplications and fusion anomalies in children often present challenging problems. The diagnostic evolution of these entities often consists of upper tract imaging to evaluate function and help diagnose obstruction, and lower tract imaging to assess reflux and at times voiding dynamics. The clinician needs to be aware of the variable presentations of these lesions, their evolution, and the therapeutic interventions that may be required to resolve problems resulting from them.