Bear paw sign (kidney)

The bear paw sign is seen in xanthogranulomatous pyelonephritis and refers to the cross-sectional appearance of the kidney which is said to resemble the paw of a bear. The renal pelvis is contracted whereas the calyces are dilated, mimicking the toe-pads of the paw.

Inspired signs
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Article Information

rID: 9946
System: Urogenital
Section: Signs
Synonyms or Alternate Spellings:
  • Bear paw sign (xanthogranulomatous pyelonephritis)

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Cases and Figures

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    Case 1: bear paw sign
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    Polar bear

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    Polar bear
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    Case 2: even seen on non-contrast CT
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    Case 3
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