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Conservative management of primary non-refluxing megaureter during the first year of life: A longitudinal
D DiRenzo1, A Persico1, M DiNicola2
1Pediatric Surgery Unit, 'G. d'Annunzio' University of Chieti and 'Spirito Santo' Hospital of Pescara, Via Fonte Romana n.8, 65124 Pescara, Italy.
Insights
This study followed children with primary non-refluxing megaureter (PM). Mild cases showed negligible complications, while moderate-to-severe cases, even with antibiotic prophylaxis, had a residual incidence of urinary tract infections (UTIs).
Area of Science:
- Pediatric Urology
- Nephrology
- Developmental Biology
Background:
- Primary non-refluxing megaureter (PM) lacks extensive prospective studies.
- This study focuses on a selected cohort of antenatally diagnosed children with PM.
- Presents outcomes during the first year of life for a longitudinal observational study.
Purpose of the Study:
- To investigate the natural history of primary non-refluxing megaureter (PM).
- To monitor complications including urinary tract infections (UTIs), hospitalizations, and surgical needs.
- To evaluate the efficacy of continuous antibiotic prophylaxis (CAP) in managing PM.
Main Methods:
- Prospective observational study of antenatally diagnosed PM cases (2007-2013).
- Follow-up included renal ultrasonography, clinical evaluation, urinalysis, and mercaptoacetyltriglycine (MAG3) scans.
- Children were grouped by dilatation severity (mild: Group A, moderate-to-severe: Group B); Group B received CAP.
Main Results:
- Included 47 children (58 PMs); 44 males, 3 females.
- Obstruction on renogram was a significant predictor for UTIs and hospitalization.
- Group A (mild dilatation) had negligible complications; Group B (moderate-to-severe) had 20% febrile UTIs and 17% hospitalization despite CAP.
Conclusions:
- Mild PM cases can be safely observed without CAP, showing negligible UTIs.
- Moderate-to-severe PM cases have residual UTIs and hospitalization risks even with CAP.
- Obstruction on MAG3 scans indicates higher risk for UTIs and hospitalization; UTIs are generally well-tolerated.
Introduction:
There is a lack of prospective studies that include a selected population of patients with primary non-refluxing megaureter (PM). Thus, a longitudinal observational study was designed to follow from birth a selected population of children with PM; all were antenatally diagnosed. In this paper, the outcomes observed in the first year of life are presented.
Objective:
The primary aim was to follow the natural history of PM. The secondary aim was to monitor the onset of any potential complications such as urinary tract infections (UTIs), need for hospitalization and need for surgical correction.
Study Design:
All children with antenatally diagnosed PM, born between January 2007 and December 2013, were prospectively followed with observational management: renal ultrasonography and clinical evaluation on a 3-month basis; urinalysis and culture in case of symptoms; and mercaptoacetyltriglycine (MAG3) nuclear scan once older than 1 month. Children presenting at birth with mild urinary tract dilatation were included in Group A; those with moderate-to-severe dilatation were included in Group B. Continuous antibiotic prophylaxis (CAP) was administered to Group B.
Results:
Forty-seven children (44 males, three females) with 58 PM were included in the study. The participants and their corresponding outcomes are shown in the summary Table. The presence of obstruction at renogram was a significant predictor of UTIs and hospitalization.
Discussion:
The strengths of this study were its prospective nature and its very consistent population. A limitation was the lack of control groups. The results regarding the negligible incidence of complications in Group A and the residual incidence of febrile UTIs (20%) and hospitalization (17%) in Group B, even with CAP, are in line with previous literature. In contrast, there was a higher risk of UTIs observed in children aged older than 6 months.
Conclusions:
Resolution or improvement is expected in all cases of PM with mild postnatal dilatation, and close to 60% of those with moderate or severe dilatation. Surgery is rarely performed on children younger than 1 year of age. It is safe to observe children with mild urinary tract dilatation without CAP, because the incidence of UTIs is negligible. In those presenting with moderate or severe urinary tract dilatation, despite CAP, a residual incidence of UTIs is seen, and symptomatic patients often require hospitalization. However, UTIs are well tolerated and do not seem to modify outcome. Cases showing obstruction on the MAG3 scan seem to be at higher risk of UTIs and hospitalization.
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