Xantogranulomatous pyelonephritis: The missed diagnosis

IntroductionXantogranulomatous pyelonephritis (XGPN) is a rare chronic inflammatory disease of the kidney that can be focal or diffuse with the focal form imitating greatly renal cell carcinoma (RCC).Presentation of caseWe report a challenging clinical case of a 38-year old male with right flank pain persisting for 3-months, imaging showed an 8 cm heterogenous mass of the upper pole of the right kidney and invading the liver. A right radical nephrectomy including the adrenal in the resection was performed under the tentative diagnosis of renal cell carcinoma (RCC) whereas histology revealed focal XGPN.DiscussionPreoperative diagnosis of focal XGPN was difficult because of radiological similarities to RCC and lack of history of stone disease or urinary tract infection.ConclusionThis case highlights the need to include XGPN in the differential diagnosis of RCC even in the era of modern imaging.