Bear paw sign

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The bear paw sign is a radiologic sign that describes the appearance of xanthogranulomatous pyelonephritis on computer tomography (CT) scans. Xanthogranulomatous pyelonephritis is a rare type of chronic pyelonephritis where the damaged areas of the kidneys are replaced by foam cells. On CT, multiloculated hypoattenuating masses with bright rim enhancement may be seen in the renal parenchyma, resembling the toe pads of a bear's paw. These masses are indicative of dilated renal calyces and xanthomas. [1]

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<span class="mw-page-title-main">Ali A Haydar</span> Lebanese physician

Ali A Haydar is Lebanese physician who is an emeritus professor at the American University of Beirut and is the Chief Medical Officer at Aman Hospital, Doha, Qatar and previously the Chairman of radiology at the Clemenceau Medical Center affiliated with Johns Hopkins International since 2018. He is also a member of the Radiological Society of North America, British society of Interventional and Cardiovascular Radiology and the Cardiovascular and Interventional Radiological Society of Europe and fellow of the Pan Arab Interventional radiology society.

<span class="mw-page-title-main">Emilio Quaia</span> Italian radiologist, academic, and author

Emilio Quaia is an Italian radiologist, academic, and author. He is a professor of Radiology and the Director of the Radiology Department at the University of Padova.

References

  1. Garrido-Abad, Pablo; Rodriguez-Cabello, Miguel Angel; Vera-Beron, Roberto; Platas-Sancho, Arturo (2018). "Bear Paw Sign: Xanthogranulomatous Pyelonephritis". Journal of Radiology Case Reports. 12 (11): 18–24. doi:10.3941/jrcr.v12i11.3415. ISSN   1943-0922. PMC   6312122 . PMID   30647833.