a case of a 54-year - old man who presented with a > 9-year history of urinary frequency and urgency and macrohematuria for the past 3 days , was examined by ultrasound scan , kidney  ureter bladder x - ray showed a large stone within the bladder , and computed tomography revealed that the stone occupied most of the bladder . a large bladder stone composed of magnesium ammonium phosphate , weighing 1048  g , and measuring 13.38.09.7 cm in size this rare case is , to the best of our knowledge , the largest bladder stone case reported to date in china . for patients with only lower urinary tract symptoms , bladder stone should be taken into consideration when other signs occur , such as recurrent urinary tract infection and hematuria . it may be associated with bladder outlet obstruction , genetic or metabolic diseases , and other environmental factors . open cystolithotomy , transurethral cystolithotripsy , shock wave lithotripsy , and percutaneous cystolithotripsy are used for it . a 54-year - old man visited our clinic with a > 9-year history of urinary frequency and urgency ; these symptoms had worsened and macrohematuria had developed within the past 3 days . the patient was a farmer , with no history of any injury , and no other lower urinary tract symptoms such as dysuria , interruption of urinary stream , and urinary retention and incontinence , except frequency and urgency , and no complaints of abdominal pain . he had a history of drinking 150  g alcohol every day for the past 20 years . and an ultrasound scan showed a small renal stone around 0.8  cm in size , hydronephrosis of both kidneys , and ureterectasia . 1 ) . computed tomography ( ct ) revealed that the large stone , sized 11.5    9.4    10.5  cm with a ct value of 789.73 to 1225.04  hu , occupied most of the bladder . his renal function was normal , and the preoperative neurological examination was normal , with no signs of neurogenic bladder . during the routine urine examination , a white blood cell count of 5/hpf and the urinary sediment assay for screening of cancer cells showed no positive results ; this was replicated 3 times . one extremely large pelvic stone and a small renal stone ( red arrow ) seen in kidney after oral antibiotic treatment for the urinary tract infection , open cystolithotomy surgery was planned . during the operation , we found that the stone was oval and not adherent to the bladder mucosa . there was no neoplasm visible to the naked eyes and the bladder outlet was unobstructed . and the stone weighed 1048  g , and measured 13.3    8.0    9.7  cm in size ( fig . 2 ) ; its transection had many compartments of stratified lamellae , composed of magnesium ammonium phosphate ( fig . the urethral catheter was removed 2 weeks later and the patient 's urinary output was normal . he was evaluated in the outpatient clinic 4 and 8 weeks after discharge with no complaints . the written informed consent for the case report was obtained from this patient , and the consent procedure was approved by the ethics committee of the second hospital of tianjin medical university . bladder calculi account for 5% of urinary calculi and usually occur because of bladder outlet obstruction , neurogenic voiding dysfunction , urinary tract infection , or foreign bodies . these patients generally present with recurrent urinary tract infection , hematuria , or urinary retention . although urinary calculi are commonly observed with renal or ureteral calculi , they may rarely occur without associated upper urinary tract calculi . our case is of particular interest because 1 extremely large bladder calculus occupied most of the bladder and pressing on the orifices of the ureters , leading to the presence of hydronephrosis . because the stone was oval and smooth , the bladder outlet was not obstructed . meanwhile , given the concomitant renal calculi , we speculate that the calculus formed after an upper urinary tract calculus descended into the bladder a long time ago , although the patient remained asymptomatic . in conclusion , the diagnostic methods of bladder calculi include ultrasound scan , plain radiography , and ct scan . satisfactory results can be achieved following surgical intervention by cystolithotomy or endoscopic cystolithotripsy , but for some giant bladder calculi , cystolithotomy is preferred . for patients with only lower urinary tract symptoms , bladder stone should be taken into consideration when other signs occur , such as recurrent urinary tract infection and hematuria .
abstractbackground : in recent years , bladder stones are increasing in china . 
 however , a giant bladder stone is rarely found nowadays.methods:a case of a 54-year - old man who presented with a > 9-year history of urinary frequency and urgency and macrohematuria for the past 3 days , was examined by ultrasound scan , kidney  ureter 
 bladder x - ray , and computed tomography . 
 then , the patient received a cystolithotomy.results:his suprapubic area was hard when palpated . 
 an ultrasound scan showed hydronephrosis of both kidneys and expanded ureters . a kidney  ureter 
 bladder x - ray showed a large stone within the bladder , and computed tomography revealed that the stone occupied most of the bladder . a large bladder stone composed of magnesium ammonium phosphate , weighing 1048  g , and measuring 
 13.38.09.7 cm in size was removed.conclusion:this rare case is , to the best of our knowledge , the largest bladder stone case reported to date in china . for patients with only lower urinary tract symptoms 
 , bladder stone should be taken into consideration when other signs occur , such as recurrent urinary tract infection and hematuria .