a 7month  old baby girl was brought to our hospital with a 2 months history of an ill defined mass involving entire abdomen . contrast enhanced computed tomography ( cect ) of the abdomen and pelvis revealed a small left kidney with a dilated renal pelvis that continued as a hugely dilated and tortuous ureter ( figure 1 ) . on a diethylene triamine pentaacetic acid ( dtpa ) micturating cystourethrogram ( mcu ) showed no reflux , with the bladder pushed laterally , probably due to the mass effect of the dilated ureter ( figure 2 ) . on cystoscopy , hemitrigone was noticed , with absent left ureteric orifice . a diagnosis of left ectopic ureter with congenital giant hydroureter and poorly functioning left kidney was made and open nephroureterectomy was done ( figure 3 ) . ct scans with a small left kidney , an extremely dilated left ureter and a displaced bladder . this case has been presented to highlight the extent to which a ureter can dilate . in case of congenital giant hydroureter the ureter is dilated out of proportion to the kidney , which is usually small and atrophic . very few such cases have been reported in literature [ 2 , 3 , 4 ] and surgeons should be aware of this entity as one of the causes of abdominal mass in an infant .
herein we present a case of a 7month  old baby girl , with left single system ectopic ureter , in whom the ureter was dilated to such an extent that it presented as an abdominal mass . 
 diagnosis was established by means of computed tomography . 
 work up was completed with renal scan and micturating cystourethrography . 
 the patient was operated and left nephorureterectomy was performed . 
 hydroureter has to be considered in differential diagnosis of abdominal mass in an infant .