A 73-year-old man was admitted ta the ICU for anuria, He reported no h
istory of urinary disease, The abdominal roentgenography and two echog
raphies showed an empty urinary bladder, a right ureteral calculus wit
hout dilatation of the urinary tract. Computed tomography demonstrated
the presence of a left ureteral stone, Bilateral retrograde ureterosc
opy and drainage allowed a rapid recovery. When the abdominal roentgen
ography and echography cannot explain the occurrence of anuria, the co
mputed tomography, or better the helical CT, can demonstrate the prese
nce of otherwise unrecognized calculi.