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Primary non-refluxing megaureters

E Merlini1, P Spina

  • 1Department of Paediatric Surgery, Ospedale Maggiore della Carità Hospital, Corso Mazzini 18, 28100 Novara, Italy. emilio.merlini@maggioreosp.novara.it

Journal of Pediatric Urology
|October 25, 2008
PubMed

Insights

Primary megaureters, a cause of hydronephrosis, often resolve on their own. However, some cases require surgical intervention to preserve kidney function.

Area of Science:

  • Pediatric Urology
  • Nephrology

Background:

  • Megaureters, characterized by ureteral dilation, can be primary or secondary, stemming from obstruction, reflux, or other causes.
  • Primary obstructed megaureter is linked to an aperistaltic and narrowed ureter segment, with specific changes in smooth muscle and collagen.
  • Primary non-refluxing megaureters account for 23% of prenatal hydronephrosis diagnoses, predominantly in males and on the left side.

Purpose of the Study:

  • To describe the etiology, diagnosis, and management of primary megaureters.
  • To outline the natural history and surgical indications for primary megaureters.

Main Methods:

  • Review of diagnostic workup including ultrasound, micturating cystourethrogram, and isotopic renogram.
  • Analysis of spontaneous regression, stability, and need for surgical intervention.
  • Description of surgical principles for primary megaureters.

Main Results:

  • Most primary megaureters exhibit spontaneous regression or stability without impacting renal function.
  • A minority (10-25%) necessitate surgery due to declining renal function, progressive dilation, or symptomatic presentation.
  • Surgical repair involves resecting the obstructing segment, ureteral size reduction, and anti-reflux reimplantation.

Conclusions:

  • Primary megaureters have a variable natural history, with many cases resolving spontaneously.
  • Timely diagnosis and monitoring are crucial to identify cases requiring surgical management.
  • Surgical techniques aim to restore normal ureteral function and prevent reflux.

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