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congenital segmental dilatation of ureter is a rare entity in children and characterized by a giant , focal segmental dilatation of mid ureter .
we report two children with segmental dilatation of ureters ; one child had ipsilateral megacalycosis and contralateral vesico - ureteric reflux ( vur ) presenting with acute renal failure and sepsis .
the other child had unilateral duplex system with segmental dilatation of both upper and lower moiety ureters with evidence of xanthogranulomatous pyelonephritis ( xgp ) in the lower moiety .
master bt , 7 years male presented with high fever and scanty , high - colored urine , and lethargy . a large lump
his blood urea and serum creatinine values at admission were 229 mg% and 5.4 mg% , respectively .
ultrasonography ( usg ) showed bilateral gross hydronephrosis and a large cyst on the left side , possibly a bladder diverticulum .
an intravenous pyelography ( ivp ) done elsewhere 2 months earlier had shown right - sided gross hydro - ureteronephrosis on right side and non - functioning left kidney .
blood urea and serum creatinine values decreased to 90 mg% and 1.7 mg% , respectively , following bilateral percutaneous nephrostomies .
exploration revealed a dilated left upper ureter ( 12 cm long ) opening into a large cyst ( 10 cm  6 cm ) , which was thick - walled and adherent to the bladder wall [ figure 1 ] . a 2 cm long lower ureter was seen from the cyst to the bladder neck .
the dilated segment along with the lower ureter was excised , and end to side ureteroureteral anastomosis was done to the contralateral ureter .
histology of dilated segment showed damaged epithelium with infiltration of sub - epithelial layers with inflammatory cells .
the patient was put on chemoprophylaxis for 6 months ( co - trimoxazole and nalidixic acid alternately every 6 weeks ) and has been asymptomatic for last 4 years .
his blood urea and serum creatinine values on last visit were 48 mg% and 1.1 mg% , respectively .
normal - looking upper ureter opening into the dilated segment ( case 1 ) a 14-month - old male child presented with abdominal distension and pain of 2 months duration .
a thick - walled cystic structure with thick fluid inside ( 4 cm  3 cm ) was noted on right side just above the bladder .
ivp showed right - sided hydronephrosis , as the radiologist missed the non - functioning lower moiety .
renal biochemical parameters were within normal limits . at operation , right - sided duplex kidney was noted .
normal size upper moiety ureter ( 8 cm long ) drains into the dilated segment ( 3 cm  2 cm ) .
the small lower moiety and dilated upper ureter ( 4 cm long ) drains into a markedly dilated , thickened ureteral segment ( 6 cm  4 cm ) .
the dilated segments were densely adherent to the bladder wall and extended up to the recto - vesical pouch .
partial nephroureterectomy ( lower moiety ) was done with excision of the dilated segment of both upper and lower moiety ureters .
normal upper moiety ureter was re - implanted into the bladder by leadbetter - politano technique .
the patient had uneventful recovery and was doing well till last follow up at 18 months .
photomicrograph ( h and e stain 200 ) showing groups of large round to oval cells with eosinophilic cytoplasm and vesicular nuclei mixed with interlacing fibrocollagenous tissue , infiltrating into the sub - epithelial stroma s / o juvenile xanthogranulomata ( case 2 )
master bt , 7 years male presented with high fever and scanty , high - colored urine , and lethargy . a large lump
his blood urea and serum creatinine values at admission were 229 mg% and 5.4 mg% , respectively .
ultrasonography ( usg ) showed bilateral gross hydronephrosis and a large cyst on the left side , possibly a bladder diverticulum .
an intravenous pyelography ( ivp ) done elsewhere 2 months earlier had shown right - sided gross hydro - ureteronephrosis on right side and non - functioning left kidney .
blood urea and serum creatinine values decreased to 90 mg% and 1.7 mg% , respectively , following bilateral percutaneous nephrostomies .
exploration revealed a dilated left upper ureter ( 12 cm long ) opening into a large cyst ( 10 cm  6 cm ) , which was thick - walled and adherent to the bladder wall [ figure 1 ] . a 2 cm long lower ureter was seen from the cyst to the bladder neck .
the dilated segment along with the lower ureter was excised , and end to side ureteroureteral anastomosis was done to the contralateral ureter .
histology of dilated segment showed damaged epithelium with infiltration of sub - epithelial layers with inflammatory cells .
the patient was put on chemoprophylaxis for 6 months ( co - trimoxazole and nalidixic acid alternately every 6 weeks ) and has been asymptomatic for last 4 years .
his blood urea and serum creatinine values on last visit were 48 mg% and 1.1 mg% , respectively .
a 14-month - old male child presented with abdominal distension and pain of 2 months duration .
a thick - walled cystic structure with thick fluid inside ( 4 cm  3 cm ) was noted on right side just above the bladder .
ivp showed right - sided hydronephrosis , as the radiologist missed the non - functioning lower moiety .
renal biochemical parameters were within normal limits . at operation , right - sided duplex kidney was noted .
normal size upper moiety ureter ( 8 cm long ) drains into the dilated segment ( 3 cm  2 cm ) . the small lower moiety and dilated upper ureter ( 4 cm long ) drains into a markedly dilated , thickened ureteral segment ( 6 cm  4 cm ) .
the dilated segments were densely adherent to the bladder wall and extended up to the recto - vesical pouch .
partial nephroureterectomy ( lower moiety ) was done with excision of the dilated segment of both upper and lower moiety ureters .
normal upper moiety ureter was re - implanted into the bladder by leadbetter - politano technique .
the patient had uneventful recovery and was doing well till last follow up at 18 months .
photomicrograph ( h and e stain 200 ) showing groups of large round to oval cells with eosinophilic cytoplasm and vesicular nuclei mixed with interlacing fibrocollagenous tissue , infiltrating into the sub - epithelial stroma s / o juvenile xanthogranulomata ( case 2 )
segmental dilatation of ureter is a rare entity , and only 12 case reports are found in the english literature .
this condition is characterized by giant , focal segmental ureteral dilatation producing an elongated and distorted ureter .
it may be associated with megacalycosis , duplication of collecting system and hypoplastic , dysplastic or non - functioning kidney .
they usually have a dysplastic or disorganized muscle coat , lined with columnar epithelial mucosa , rather than the usual transitional epithelium . the associated kidney or the moiety may be hypoplastic or the site of comparatively mild hydronephrosis associated with atrophic renal parenchyma .
ramaswamy et al . reported a case of congenital segmental megaureter with sparing of the proximal and distal ureter .
the authors suggested that attenuated nexuses and thin myofilaments might be responsible for this entity .
soler reported a case of an unilateral multicystic dysplastic kidney and contralateral megacalycosis associated with ipsilateral distal segmental megaureter .
pinter speculated abnormal recanalization of the solid ureteral duct during development as a possible cause .
xgp is an atypical form of chronic pyelonephritis characterized by diffuse , focal or segmental suppurative destruction of renal parenchyma .
urinary tract obstruction , urosepsis , renal ischemia , lymphatic obstruction , and altered immune response may be responsible for xgp . in the rare localized form , the lesion can be confined to one or other pole , as was seen in our second case .
its association with duplex kidney is known , but its association with segmental dilatation of ureter has not been reported earlier .
the treatment of segmental dilatation of ureter is excision of the diseased segment with end - to - end ureteroureterostomy .
a better option is to anastomose the upper ureter end - to - side to the contralateral ureter , as was done in our first case .
localized form of the disease , as in our 2 case , is rare , and a partial nephrectomy is ideal .
these patients need long - term follow up as secondary amyloidosis has been reported in association with xgp .
segmental dilatation of ureter is a giant , focal segmental ureteral dilatation producing an elongated and distorted ureter . 
 two children presented with this condition , one had ipsilateral megacalycosis and contralateral vesicoureteric reflux . 
 the other had duplication of the kidney . 
 the non - functioning lower moiety showed structure of xanthogranulomatous pyelonephritis .