Presentation
Presents to outpatient sonography after right renal colic.
Patient Data
The kidneys are normal size and show regular margins. Longitudinal and transverse images of both kidneys show strongly echogenic renal pyramids and a cyst at the lower pole, containing small calcification on the left. There are no signs of hydronephrosis. Bladder without stones.
Case Discussion
The renal pyramids are highly echogenic, strongly suggestive of medullary sponge kidney (MSK) with medullary nephrocalcinosis. Medullary sponge kidney occurs because of focal or diffuse dilation of the medullary collecting tubules with stasis of urine and may eventually lead to calculi deposits. On ultrasound exam it appears as hyperechoic calyces when stones begin to form in the dilated collecting tubules. Smaller calcifications do not shadow while larger stones can produce shadowing. Nephrocalcinosis is the formation of diffuse deposits of calcium throughout the kidneys.
Radiographer: TSRM Fabio Imola