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Published on: October 12, 2017
Clinical implications of primary "occult" vesicoureteral reflux in male children
Stefano Guarino1, Anna Di Sessa1, Giulio Rivetti1
1Department of Woman, Child and of General and Specialized Surgery, Università degli Studi della Campania "Luigi Vanvitelli", Via Luigi De Crecchio 2, Naples, Italy.
Insights
Occult vesicoureteral reflux (VUR) is missed in 23.6% of boys during voiding cystourethrography (VCUG), posing risks for kidney injury (KI) and febrile urinary tract infections (fUTI). Isotopic cystography (IC) can identify this occult VUR for timely intervention.
Area of Science:
- Pediatric Urology
- Diagnostic Imaging
- Nephrology
Background:
- Vesicoureteral reflux (VUR) is a common condition in children, increasing the risk of febrile urinary tract infections (fUTI) and kidney injury (KI).
- Voiding cystourethrography (VCUG) is the standard diagnostic tool, but may miss cases of VUR, termed "occult" VUR.
Purpose of the Study:
- To compare the characteristics and outcomes of occult VUR detected by isotopic cystography (IC) versus VUR detected by VCUG in male children.
- To assess the risk of KI and fUTI associated with occult VUR.
Main Methods:
- Retrospective enrollment of male children undergoing both VCUG and IC between 2015-2020.
- Kidney injury (KI) defined by abnormal estimated glomerular filtration rate, blood pressure, or proteinuria.
- Follow-up duration of 5.3 years.
Main Results:
- Of 421 males, 23.6% (47/199) had occult VUR detected by IC. Patients with occult VUR showed a non-negligible risk of KI and fUTI.
- VCUG-diagnosed VUR had a higher prevalence of dilated VUR and scintigraphic damage compared to occult VUR.
- Both VCUG-detected and occult VUR were associated with an increased risk of fUTI and KI at follow-up.
Conclusions:
- Occult VUR is present in a significant proportion of male children and carries risks for KI and fUTI.
- IC can identify occult VUR in boys with recurrent fUTIs and negative VCUG, potentially guiding surgical intervention for dilated cases.
Objectives:
To compare characteristics and outcomes of vesicoureteral reflux (VUR) detected solely on isotopic cystography (IC) ("occult" VUR) with voiding cystourethrography (VCUG)-detected VUR.
Materials And Methods:
Between 2015 and 2020, we retrospectively enrolled all male children first undergoing VCUG and, if negative, IC in the same session. Kidney injury (KI) was defined by abnormal estimated glomerular filtration rate and/or blood pressure and/or proteinuria.
Results:
We enrolled 421 males with a median age of 3 months and a follow-up of 5.3 years. None exhibited KI initially, but 10% of those with VUR developed KI during follow-up. Two hundred and twenty-two patients (52.7%) did not show VUR, 152 (36.1%) had VCUG-diagnosed VUR, and 47 (11.2%) had occult VUR. Therefore, 47/199 patients (23.6%) with VUR had occult VUR. Among these, 34/47 (72.3%) had dilated VUR, and 22/47 (46.8%) exhibited split renal function < 45% and/or scar (scintigraphic damage). Compared to patients with occult VUR, those with VCUG-diagnosed VUR showed a similar prevalence of febrile urinary tract infection (fUTI) before and after VUR diagnostics and KI at the last follow-up but a higher prevalence of dilated VUR, of scintigraphic damage, and underwent surgery more frequently. At multiple logistic regression analysis, patients with VCUG-diagnosed VUR presented an increased risk of fUTI either before or after VUR diagnosis and of KI, while patients with occult VUR presented an increased risk of fUTI before (and among patients with dilated VUR also after) VUR diagnosis and of KI.
Conclusion:
Occult VUR affects 23.6% of male children with VUR with a non-negligible risk of VUR-associated KI and fUTI. IC could select, among males with recurrent fUTIs and negative VCUG, those requiring surgery for a possible dilated occult VUR.
Clinical Relevance Statement:
Vesicoureteral reflux may be overlooked in 25% of boys during VCUG, yet they are at risk of fUTIs and KI. In case of recurrent infections post-negative cystourethrography, IC could detect occult reflux, guiding surgical intervention.
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