Bear paw sign (kidney)

A.Prof Frank Gaillard et al.

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

  • Case 1: bear paw sign
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  • Polar bear (photo)
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  • Case 2: even seen on non-contrast CT
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  • Case 3
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