Investig Clin Urol.  2017 Jun;58(Suppl 1):S14-S22. 10.4111/icu.2017.58.S1.S14.

Critical appraisal of the top-down approach for vesicoureteral reflux

• Abdelhalim A
• Khoury AE

• KMID: 2379891
• DOI: http://doi.org/10.4111/icu.2017.58.S1.S14

Abstract

Vesicoureteral reflux (VUR) has been linked to recurrent urinary tract infections (UTIs), renal scarring, hypertension, renal insufficiency and end-stage kidney disease. Different imaging strategies have been proposed to approach children presenting with UTI to sort out patients with significant VUR while minimizing patient morbidity, radiation exposure and financial burden. None of these imaging strategies is universally accepted. The"top-down approach" (TDA) aims at restricting the number of voiding cystourethrograms (VCUGs) and its associated morbidity while identifying patients with clinically-significant reflux. In this approach, children presenting with febrile UTIs are acutely investigated with dimercapto-succinic acid (DMSA) renal scans to identify patients with renal parenchymal inflammation. Those with evidence of renal affection are offered VCUG and late DMSA scan to identify VUR and permanent renal scarring, respectively. Although TDA could identify clinically-significant VUR with high sensitivity, it is not without limitations. The approach segregates patients based on the presence of DMSA cortical lesions omitting the morbidity and the economic burden of UTI. Additionally, some of DMSA lesions are attributed to congenital dysplasia and unrelated to UTI. Ionizing radiation exposure, financial costs, limited availability of DMSA scans in the acute setting, variability in interpreting the results and low yield of actionable findings on DMSA scans are some other limitations. In this review, we tried to address the drawbacks of the TDA and reinforce the value of patient-centered approach for VUR.

Keyword

Cost-benefit analysis; Ionizing radiation; Technetium Tc 99m dimercaptosuccinic acid; Urinary tract infections; Vesicoureteral reflux

MeSH Terms

Child
Cicatrix
Cost-Benefit Analysis
Humans
Hypertension, Renal
Inflammation
Kidney Failure, Chronic
Outpatients
Radiation Exposure
Radiation, Ionizing
Succimer
Technetium Tc 99m Dimercaptosuccinic Acid
Urinary Tract Infections
Vesico-Ureteral Reflux*
Succimer
Technetium Tc 99m Dimercaptosuccinic Acid

Figure

• 

  Fig. 1 (A) The prevalence of vesicoureteral reflux (VUR) based on ultrasound findings in children presenting with febrile urinary tract infection (UTI) [131522333445]. (B) The prevalence of VUR based on acute dimercapto-succinic acid (DMSA) findings in children presenting with febrile UTI [121314224344]. RBUS, renal bladder ultrasound.

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