Cholesteatoma of the upper urinary tract.

Cholesteatoma of the urinary tract is a rare condition which can be diagnosed radiographically. The radiographic findings of stringy intraluminal defects or nodules that may lightly calcify or coalesce to form a discrete mass in association with calculi and/or obstruction are characteristic. A history of chronic urinary tract infection, renal colic, and desquamated epithelial cells in the urine further support the diagnosis.