Abstract
Bladder stones comprise 5% of urinary tract stones. Generally, they occur in the presence of bladder neck obstruction, urinary tract infections associated with neurogenic bladder and foreign objects. They are more common among men than women. Infection stones comprise approximately 15% of urinary tract stones. A giant bladder stone is a rare finding in contemporary urological practice. The general clinical setting is recurrent urinary tract infections, hematuria and urinary retention. We performed an open cystolithotomy on a mentally impaired patient who had a giant bladder stone. The stone removed weighed 465 grams. There was no evidence of any infravesical obstruction on the cystoscopy performed before the operation or during the operation. The stone consisted of 75% carbonate apatite and 25% struvite. Given that such a stone was found in a mentally impaired patient indicates that infection stones can form without infravesical obstruction.