What is Xanthogranulomatous pyelonephritis?

a rare and aggressive variant of chronic pyelonephritis resulting in a non-functioning kidney. It is most often associated with chronic obstruction and stones with ongoing infection.

What is the pathophysiology of Xanthogranulomatous pyelonephritis?

• The kidney is eventually replaced by a mass of reactive tissue
• Foamy (lipid-laden) macrophages predominate

What is the causative bacteria of Xanthogranulomatous pyelonephritis?

Various, but commonly Escherichia coli and Proteus mirabilis