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A Murine Model of Irreversible and Reversible Unilateral Ureteric Obstruction
Published on: December 20, 2014
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Non-refluxing Primary Megaureter in Children Resolves From Proximal to Distal
Harkanwal Randhawa1, Conor Jones1, Melissa McGrath2
1Division of Urology, Department of Surgery, McMaster University, Hamilton, Ontario, Canada.
Urology
|September 30, 2023
Summary
Spontaneous resolution of non-refluxing primary megaureter (NRPM) in children typically progresses from proximal to distal. Distal ureteral dilation may take up to 10 months longer to resolve than proximal segments.
Area of Science:
- Pediatric Urology
- Medical Imaging
- Nephrology
Background:
- Non-refluxing primary megaureter (NRPM) is a congenital condition characterized by ureteral dilation without vesicoureteral reflux.
- Understanding the natural history and resolution patterns of NRPM is crucial for appropriate patient management and monitoring.
- Prenatal hydronephrosis (HN) is a common finding, and NRPM is one of its potential causes.
Purpose of the Study:
- To evaluate the spontaneous resolution of ureteral dilation in children diagnosed with NRPM.
- To determine the pattern of resolution, specifically whether it occurs proximally to distally or distally to proximally.
Main Methods:
- A prospective cohort of 92 children with NRPM was identified from a prenatal hydronephrosis database (0-24 months).
- Exclusion criteria included prior surgery, less than 6 months follow-up, or absence of a voiding cystourethrogram (VCUG).
- Ureteral segments (proximal, mid, distal) were analyzed for resolution based on Society for Fetal Urology (SFU) grading, anteroposterior diameter (APD), and ureteral diameter, using descriptive statistics and Kaplan-Meier curves.
Main Results:
- Of 66 eligible patients, 76% showed overall HN resolution.
- Resolution rates varied by ureteral segment: 83% for proximal, 72% for mid, and 33% for distal segments.
- Distal ureteral segments demonstrated significantly slower resolution rates compared to proximal and mid-segments (P < .01).
Conclusions:
- Spontaneous resolution of NRPM in children generally follows a proximal-to-distal progression.
- Distal ureteral dilation requires a longer resolution period, potentially up to 10 months longer than proximal segments.
- These findings aid in predicting the natural course of NRPM and managing patient expectations.
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