Bilateral Nephroblastomatosis With a Unilateral Wilms Tumor: A Case Report Highlighting Imaging Characteristics.

Nephrogenic rests (NRs) are foci of embryonic nephrogenic cells that persist beyond the 36th week of gestation. They are precursor lesions of Wilms tumor and are found incidentally in approximately 1% of infants. The term nephroblastomatosis (NBS) is utilized when nephrogenic rests extensively or multifocally affect the kidneys.