Herein we report the confirmation of fungus balls (circular collections of C.tropicalis) during a transurethral ureterolithotomy, which is as far as we know the first reported instance. A-61-year old man was referred to the urology department with bilateral ureteral calculi. Initially a transurethral ureterolithotomy was attempted but residual stones existed. During the second operation, we found numerous white fluffy material in the renal pelvis. Because of them, we were unable to have a clear field of vision to complete operation. During the third operation, we found the fungus balls again and cultured them. Cultures yielded C.tropicalis.
Keywords: fungus ball; ureteral calculi.