Discussion
Fetal ultrasound examination enables us to diagnose and follow the progress of obstructive uropathies, including the occurrence of fetal urinomas preservation of renal function is less effective when urinomas occur in utero. The factors necessary for its formation had been suspected for some time, and are now well established: (1) existing renal malfunction; (2) an underlying obstruction; and (3) rupture of the collecting system.The differential diagnosis includes hydronephrosis, cystic renal disease,duplication of the intrarenal collecting system, cystic renal tumor, cystic lymphangioma, cystic neuroblastoma, mesenteric cyst and enteric duplication cyst.The prognosis was better in cases of PUV than in UPJO It and a very poor functional prognosis and the subsequent life‐threatening risk (from, for example, oligohydramnios or pulmonary hypoplasia) in cases of bilateral urinomas or urinoma in a single kidney. In‐utero puncture only appears to be justified in cases where the urinoma has a mass effect on adjacent major structures (especially the contralateral kidney), or in the case of probable dystocia. If a puncture is performed, a recurrence after aspiration is highly likely and repeat punctures or the initial installation of a more permanent shunt could be offered.
Conclusions
Although the precise causes of urinomas are still unknown, this review shows that in the event of a fetal urinoma, the probability of a non-functional dysplastic ipsilateral kidney lies at around 80%. In-utero puncture only appears to be justified in cases where fluid accumulation has mass effects on adjacent major structures.
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