Related Experiment Video
Updated: May 14, 2026

Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection
Published on: October 12, 2017
Postnatal evaluation of intrauterine hydronephrosis due to ureteropelvic junction obstruction
Carlos Augusto Fernandes Molina1, Inalda Facincani, Valdair Francisco Muglia
1Division of Urology, Department of Surgery and Anatomy, Ribeirão Preto Faculty of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil.
Purpose:
Fetal hydronephrosis is a frequent finding due to advances in prenatal ultrasonography. The definition of fetal and neonatal urinary tract obstruction is a very difficult task requiring confirmation of reduced renal function and hydronephrosis. In this study we followed a series of consecutive patients with intrauterine hydronephrosis that persisted during post-natal life.
Methods:
116 newborns with antenatal hydronephrosis diagnosed by ultrasound and submitted to a specific post-natal evaluative protocol with a follow-up period of 6 years.
Results:
In 45 (38.8%) of 116 patients, ureteropelvic junction (UPJ) obstruction was confirmed and surgical correction of the UPJ obstruction was done in 19 patients. From 26 children who were initially submitted to non-surgical treatment, only 6 (23%) needed a surgical approach during follow up. Overall analysis showed that surgery was performed in 25 patients with UPJ obstruction, and the others 20 patients were kept under clinical observation, since normal renal function was confirmed by scintigraphy scans.
Conclusion:
Fetal hydronephrosis due to UPJ obstruction deserves careful postnatal evaluation. UPJ obstruction is the most frequent anomaly and its surgical treatment has very precise indications. The evaluative protocol was useful in identify patients that could be followed-up with a non-surgical approach.
Related Concept Videos
Imaging Studies V: Intravenous Urography and Retrograde Pyelography
Urodynamic Studies: Uroflowmetry
Imaging Studies VI: Voiding Cystourethrography and Cystography
Nursing Assessment of the Genitourinary System II: Inspection and Palpation
Imaging Studies II: Ultrasonography
Imaging Studies I: Kidney, Ureter, and Bladder Studies

