Unusual case of urothelial carcinoma disguised as xanthogranulomatous pyelonephritis and causing reno-colic fistula: Case report and review of literature.

Xanthogranulomatous pyelonephritis is a rare and aggressive form of chronic pyelonephritis, it can occur at all age groups but is more common in women than in men, supposedly relating to the increased incidence of urinary tract infections and chronic nephrolithiasis in woman. Computed tomography (CT) findings are very helpful in making the correct diagnosis, but the definitive diagnosis is still based on histology, as there are many differential diagnoses such as renal cell carcinoma and renal tuberculosis. The complications of this type of pyelonephritis are due to the involvement of adjacent organs.