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Case of the Week 322

What's the most likely diagnosis?

  • 28 year-old with flank pain

Contrast-enhanced CT Urogram with inset of right kidney

  1. Renal cell carcinoma
  2. Pyelopnephritis
  3. Transitional cell carcinoma
  4. Medullary sponge kidneys
  5. Renal laceration

Additional Images - Unenhnaced CT of both kidneys


Additional Images

Unenhanced axial CT images of both kidneys


4. Medullary sponge kidneys

More (Click Discussion Tab)

Medullary Sponge Kidneys

General Considerations

  • Developmental dilatation of the collecting tubules in the medullary pyramids of kidneys
  • Usually in people 10-30 years old
  • Pathogenesis is not known
  • Multiple cysts connect the collecting tubule with the papillary ducts or calyces
    • The cysts may contain calcifications
    • Stones are usually calcium apatite and calcium oxalate or calcium apatite alone

More ...

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