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Case of the Week 343

What's the most likely diagnosis?

  • 36 year-old undergoing retrograde pyelogram

Left Kidney-Retrograde Pyelogram

  1. Renal laceration
  2. Hepato-renal fistula
  3. Pyelovenous backflow
  4. Retroperitoneal fibrosis
  5. Staghorn calculus

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3. Pyelovenous backflow



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Pyelovenous Backflow

General Considerations

  • Refers to the retrograde flow of contrast material out of the intrarenal collecting system due to a small rupture of a calyceal fornix
  • Almost always seen with increased pressure in the collecting system such as from
    • Retrograde pyelography
      • Majority of cases
    • Antegrade pyelography (urogram), due to obstruction of the collecting system almost always by a ureteral calculus
      • Less common
      • Obstruction is usually in the ureter
      • Rupture decompresses collecting system
    • Rarely, from vesico-ureteral reflux

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