Xanthogranulomatous pyelonephritis presenting as a type IV renal cyst

Area of Science:

• Nephrology
• Urology
• Pathology

Background:

• Xanthogranulomatous pyelonephritis (XGP) is a rare, chronic destructive inflammatory disease of the kidney.
• It is often associated with nephrolithiasis and urinary tract obstruction.
• XGP can mimic renal tumors, posing diagnostic challenges.

Purpose of the Study:

• To report a case of a young woman with a Bosniak class IV renal cyst.
• To highlight the histopathological diagnosis of xanthogranulomatous pyelonephritis in this context.
• To discuss the diagnostic considerations and management of such cases.

Main Methods:

• A case presentation of a 20-year-old woman with lumbar back pain.
• Diagnostic imaging using contrast-enhanced computed tomography (CT) scan.
• Surgical management with radical nephrectomy and subsequent histopathological examination.

Main Results:

• CT scan identified a Bosniak class IV renal cyst, suggesting malignancy.
• Histopathology confirmed xanthogranulomatous pyelonephritis, not a renal cell carcinoma.
• The patient's symptoms of back pain were attributed to the underlying kidney condition.

Conclusions:

• Bosniak class IV renal cysts require thorough investigation due to their high risk of malignancy.
• Xanthogranulomatous pyelonephritis can present as a complex cystic mass, mimicking renal cancer.
• Radical nephrectomy may be necessary for diagnosis and treatment of XGP, even in younger patients.