title: [Diuretic renography in the diagnostic approach of prenatal hydronephrosis].
abstract: OBJECTIVE
  To verify the utility of diuretic renography using 99mTc-MAG3 in the evaluation of the urinary tract obstruction in patients with prenatal diagnosis of hydronephrosis. In a neonate with upper urinary tract dilatation, it is difficult to differentiate a true obstruction from a dilated non-obstructed system.
  
  
  METHODS
  The retrospective study (january 1993-december 1998) included 40 consecutive patients selected from 181 newborns with a prenatal diagnosis of hydronephrosis. The mean age of the performance of the first renography was 2.6 months.
  
  
  RESULTS
  The final diagnosis (once the vesicoureteral reflux was ruled out) was: ureteropelvic junction obstruction (UPJ) 16, megaureter 15, ureterocele 3 and stasis 6. Conservative treatment was applied in most of the patients. Nevertheless, 17 of them needed surgical treatment due to the high risk of the permanent renal damage.
  
  
  CONCLUSIONS
  1) UPJ is the most frequent cause of neonatal hydronephrosis (NH) and consequently, of the request for diuretic renographies. The renography with 99mTc-MAG3 has the greatest influence in the therapeutic decision (identifying who should be operated on and when this should be done), due to the fact that it is the disease with the highest rate of surgical interventions. 2). The surgical indication in NH is based on the diuretic renography parameters and/or on the presence of symptomatology. In our series of surgical patients, none of those who had a differential renal function <20% with regard to the contralateral one showed recuperation after surgery (control 6 months later).
authors.affiliation: Servicio de Medicina Nuclear, Hospital Santiago Apóstol, Vitoria. jcortes@hsan.osakidetza.net
authors.forename: J
authors.initials: J
authors.lastname: Cortés Hernández
authors.forename: J I
authors.initials: JI
authors.lastname: Alonso Colmenares
authors.forename: S
authors.initials: S
authors.lastname: Alvarez Ruiz
authors.forename: E
authors.initials: E
authors.lastname: Rodeño Ortiz de Zárate
authors.forename: B
authors.initials: B
authors.lastname: Orive Olondriz
authors.forename: A M
authors.initials: AM
authors.lastname: Gonzalo
authors.forename: P
authors.initials: P
authors.lastname: Alcorta Armentia
mesh_terms: D004231:Diuresis; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging*; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D011296:Prenatal Diagnosis; D011866:Radioisotope Renography; D012189:Retrospective Studies