Presentation
Recurrent renal stone disease, admitted with flank pain and fever
Patient Data
Age: 50 years
Gender: Female
From the case:
Xanthogranulomatous pyelonephritis
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Right-sided staghorn calculus.
From the case:
Xanthogranulomatous pyelonephritis
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Large right staghorn calculus, with ultrasound demonstrating dilated fluid filled spaces, without hydronephrosis.
'Bear's paw' appearance of dilated fluid filled spaces in the kidney with a central staghorn calculus.
From the case:
Xanthogranulomatous pyelonephritis
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Large right staghorn calculus, with ultrasound demonstrating dilated fluid filled spaces, without hydronephrosis. This is elegantly shown on CT with an enlarged right kidney, with a bear's paw appearance of xanthogranulomatous pyelonephritis (XPN) with a small perinephric collection.
Case Discussion
Classical appearances of XPN with a bear paw sign.