Xanthogranulomatous pyelonephritis
Presentation
Upper abdominal discomfort, vague constitutional symptoms and reduced renal function.
Patient Data
Abdominal x-ray
X-ray demonstrates a large right sided branched calculus which appears fragmented.
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CT demonstrates enlargement of the right kidney with multiple large renal calculi and rounded low density regions associated with the calculus. The left kidney is markedly atrophic.
Single image from the CT with the right kidney outlined. Note how the dilated low density calyces form an appearance which has been likened to that of the pads of a bear paw.
MRI abdomen
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MRI demonstrates an enlarged right kidney with heterogeneous signal, hydronephrosis and a staghorn calculus.
Case Discussion
Features are consistent with xanthogranulomatous pyelonephritis and pre-existing staghorn calculus.
Case courtesy of Dr Laura Jimenez Juan (CT) and Dr Natalie Yang (MRI)