Xanthogranulomatous Pyelonephritis Can Simulate a Complex Cyst: Case Description and Review of Literature.

Xanthogranulomatous pyelonephritis is a rare and peculiar form of chronic pyelonephritis and is generally associated with renal lithiasis. Its incidence is higher in females. The peculiarity of this disease is that it requires a differential diagnosis, because it can often simulate dramatic pathologic conditions. In fact, in the literature are also described cases in association with squamous cell carcinoma of the kidney The radiologic clinical findings simulate renal masses, sometimes in association with caval thrombus. We describe a case of xanthogranulomatous pyelonephritis with radiologic aspects of a complex cyst of Bosniak class III in a man 40-year old.