Bear paw sign (kidney)

Last revised by Mohammad Taghi Niknejad ◉ on 10 Jul 2024

Citation, DOI, disclosures and article data

Citation:

Gaillard F, Niknejad M, Ibrahim D, et al. Bear paw sign (kidney). Reference article, Radiopaedia.org (Accessed on 22 Mar 2025) https://doi.org/10.53347/rID-9946

DOI:

https://doi.org/10.53347/rID-9946

Permalink:

https://radiopaedia.org/articles/9946?embed_domain=hackmd.io%25252525252525252F%252525252525252540yipuafecsl2jsu8smr5njq%25252525252525252Fbnjhjgjghjghjgh

rID:

9946

Article created:

1 Jun 2010, Frank Gaillard ◉ ◈

Disclosures:

At the time the article was created Frank Gaillard had no recorded disclosures.

View Frank Gaillard's current disclosures

Last revised:

10 Jul 2024, Mohammad Taghi Niknejad ◉

Disclosures:

At the time the article was last revised Mohammad Taghi Niknejad had no financial relationships to ineligible companies to disclose.

View Mohammad Taghi Niknejad's current disclosures

Revisions:

13 times, by 10 contributors - see full revision history and disclosures

Systems:

Urogenital

Sections:

Signs

Tags:

refs, kidney, infection, cases

Synonyms:

Bear paw sign (xanthogranulomatous pyelonephritis)

The bear paw sign refers to the cross-sectional appearance of the kidney affected by xanthogranulomatous pyelonephritis. There is a radial arrangement of multiple, low attenuation rounded spaces representing dilated calyces, surrounded by thin renal parenchyma that has higher attenuation or contrast enhancement, mimicking the appearance of the dark toe pads on a polar bear's paw.