( 1 ) patients may report dysuria , intermittency , haematuria , frequency , hesitancy , nocturia or sudden termination of voiding . a 62 year old lady presented to the hospital with a swelling in her right thigh . she had a past history of myelomeningocele spina bifida which had been closed at birth . she suffered from urinary incontinence and had been managed with long term suprapubic catheters for 20 years . she had required a vesicolithotomy via a midline incision and a vaginal hysterectomy 13 years previously . initial examination revealed a swollen right thigh and a calcified mass protruding through the skin in the right groin . a strong smell of urine was noted although it was thought that this was secondary to a leakage from around the site of her supra pubic catheter . laboratory data demonstrated normal renal function , a raised c - reactive protein and normal white cell count . due to her swollen right leg a deep vein thrombosis was excluded with an ultrasound scan and negative d dimer and plain radiographs of her right hip and pelvis were requested . a urology opinion was sought , initially , with regard to management of the suprapubic catheter . on closer examination , urine was noted to be leaking not from the suprapubic site but around the calcified mass in the right groin and a diagnosis of vesicocutaneous fistula was made . her radiographs demonstrated two urinary calculi ( fig 1 ) and she went on to have an abdominal computed topography scan ( fig 2 ) which confirmed the diagnosis of a vesicocutaneous fistula . plain radiographs demonstrating two bladder calculi ct demonstrating the two bladder calculi pointing towards the right groin vesicolithotomy was performed removing the calculi by enlarging the fistulous opening . ( fig 3 ) two calculi measuring 40 mm  43 mm  30 mm and 43 mm  50 mm  33 mm were extracted . 4 ) the suprapubic catheter was changed and the fistula was left open and urine leakage continued to decrease in quantity until the fistula tract closed . intraoperative view of the bladder calculi emerging through the vesicocutaneous fistula into the right groin the two bladder calculi following extraction urological complications are often a major source of morbidity for these patients . ( 5 ) abnormal bladder sensation and function combined with sphincter dysnergia predispose the spina bifida patient to urinary stasis , recurrent urinary tract infections , stone formation and renal function impairment . ( 5 ) management of the problem can be difficult and may include the use of anti - cholinergics , intermittent self catheterisation ( isc ) , supra pubic catheterisation or surgical intervention to allow urinary diversion . ( 6 ) increased fluid intake , weekly changes of indwelling catheters if isc is not possible and regular ultrasonic screening , to pick up stone formation at an early stage , may help reduce the burden of these problems . ( 2 - 4 ) predisposing factors to bladder stone formation include urinary stasis , bladder outflow obstruction urinary stasis , recurrent urinary tract infections and foreign bodies within the bladder ( 1 ) , all of which can be seen in spina bifida patients . in our case the added sensory abnormalities secondary to spina bifida left the bladder calculus undiagnosed until it had formed the vesicocutaneous fistula . good control of the predisposing factors can dramatically reduce the risk of developing bladder calculi , but especially in cases where this is difficult , a high index of suspicion , regular urological review and timely uss can prevent the development of both the bladder calculus and its complications .