Renal lymphangiomatosis: a rare cause of bilateral nephromegaly.

We report the ultrasound, excretory urography and MR findings in a young child with renal lymphangiomatosis who presented with gradually progressive bilateral flank swelling but who was otherwise asymptomatic. The typical perirenal and parapelvic cysts are visualized as hypoechoic lesions on sonography and hyperintense on T2-weighted HASTE images. T1-weighted image could not delineate the cysts clearly. The renal parenchyma was hyperechoic on sonography, and MRI showed reversal of the normal corticomedullary signal intensity, and confirmed the diagnosis by suggesting the non-parenchymal origin of the cysts.