Bilateral xanthogranulomatous pyelonephritis involving native kidneys in a renal transplant recipient: association with renal cell carcinoma and amyloidosis.

An unusual case of a 44-year-old male renal transplant recipient who developed bilateral xanthogranulomatous pyelonephritis (XPN) of his native kidneys is presented. Bilateral nephrectomy specimens showed classic features of XPN. In addition, there was amyloidosis involving both kidneys and a small renal cell carcinoma in the left kidney. To the best of our knowledge, such a combination of pathologic conditions in one patient has not been previously reported.