Clinical Presentation

A 3-year-old boy undergoing ultrasound for abdominal pain.

Further Work-up

(A,B) US: There is a hypoechoic round mass at the lower pole of the left kidney with internal blood flow (arrow). (C–E) Computed tomography (CT): There are small, homogeneous, low-density nodules in the periphery of the kidneys (arrows). They do not enhance as strongly as the normal renal cortex.

Differential Diagnosis

• Nephroblastomatosis: Multiple small, solid, homogeneous renal masses are consistent with nephroblastomatosis.

• Wilms tumor: