A huge pelvic calculus causing acute renal failure.

We present a 69-year-old man with repeated urinary tract infection and lower abdominal pain. Kidney-ureter-bladder (KUB) scout film showed a huge, 320-g triangular pelvic calculus that was surgically removed with excellent results. Bladder stone is a common disease, but it is rare for such a calculus to be so large as to cause bilateral hydronephrosis. Surgical intervention by cystolithotomy or endoscopic cystolithotripsy can achieve satisfactory results. Bladder outlet obstruction should be treated simultaneously. Close follow-up, however, is mandatory because the recurrence of urolithiasis is high in those patients with voiding problems and recurrent urinary infection. To the best of our knowledge, this is the largest bladder stone in a human male. This case report also illustrates the importance of radiologic evaluation of patients with repeated urinary infections.