Giant hydroureteronephrosis of the upper pole in pediatric duplex collecting systems: two cases study

Nguyen Thi Mai Thuy, Nguyen Phuong Thao, Do Van Khang

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Abstract

Giant dilation of the upper moiety in a duplex collecting system is a rare congenital anomaly, often diagnosed late due to its asymptomatic progression. We report two pediatric cases with a history of prenatally diagnosed urinary tract dilation who lacked regular postnatal follow-up. Case 1 involves a 5-year-old female patient presenting with a massive 1,100 mL dilation that caused severe compression and anatomical distortion of adjacent structures, rendering magnetic resonance urography (MRU) unable to identify the duplex morphology. Case 2 involves a 2-year-old male patient with a 1000 mL dilation, in which MRU successfully differentiated the two renal moieties preoperatively. Both patients underwent an upper pole heminephroureterectomy with successful preservation of the lower moiety. Postoperative follow-up at 9 to 11 months demonstrated stable morphology and preserved parenchymal integrity of the lower pole. Upper pole heminephroureterectomy may be a feasible option in selected cases with a non-functioning upper moiety and preserved lower moiety.

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References

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