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Distal Ureteral Diameter Ratio is Predictive of Breakthrough Febrile Urinary Tract Infection
Angela M Arlen1, Traci Leong2, P Joseph Guidos3
1Department of Urology, University of Iowa Hospitals and Clinics, Iowa City, Iowa; Department of Pediatrics, University of Iowa Hospitals and Clinics, Iowa City, Iowa.
Insights
A larger distal ureteral diameter ratio in children with vesicoureteral reflux predicts a higher risk of breakthrough febrile urinary tract infections, aiding in management decisions.
Area of Science:
- Pediatric Urology
- Nephrology
- Radiology
Background:
- Vesicoureteral reflux (VUR) is a common condition in children, increasing the risk of urinary tract infections (UTIs).
- Identifying children at high risk for recurrent febrile UTIs is crucial for effective management and prevention of kidney damage.
- The distal ureteral diameter ratio (UDR) is an objective measure that has shown prognostic value for spontaneous VUR resolution.
Purpose of the Study:
- To evaluate the utility of the ureteral diameter ratio (UDR) as a predictive factor for breakthrough febrile urinary tract infections (UTIs) in children with primary VUR.
- To determine if UDR can help identify children at increased risk for recurrent febrile UTIs, independent of VUR grade.
Main Methods:
- A retrospective analysis of children diagnosed with primary VUR and undergoing voiding cystourethrogram (VCUG).
- Ureteral diameter ratio (UDR) was calculated by dividing the largest pelvic ureteral diameter by the distance between L1 and L3 vertebral bodies.
- Univariate and multivariable analyses were performed to assess the association between UDR, VUR grade, bladder-bowel dysfunction, and breakthrough febrile UTIs.
Main Results:
- The study included 140 children (112 girls, 28 boys) with a mean age of 2.5 years at diagnosis.
- A total of 40 children (28.6%) experienced breakthrough febrile UTIs during a mean follow-up of 3.2 years.
- Children with breakthrough febrile UTIs had a significantly greater mean UDR (0.36) compared to those without (0.25) (p = 0.004).
- Each 0.1 unit increase in UDR was associated with a 1.7-fold increased odds of breakthrough infection, even after controlling for VUR grade (p < 0.0001).
Conclusions:
- An increased distal ureteral diameter ratio is a significant independent risk factor for breakthrough febrile UTIs in children with VUR.
- Ureteral diameter ratio provides valuable prognostic information regarding the risk of recurrent pyelonephritis.
- UDR can assist clinicians in making informed management decisions for children with VUR and recurrent UTIs.
Purpose:
Distal ureteral diameter ratio is an objective measure that is prognostic of spontaneous resolution of vesicoureteral reflux. Along with likelihood of resolution, improved identification of children at risk for recurrent febrile urinary tract infections may impact management decisions. We evaluated the usefulness of ureteral diameter ratio as a predictive factor for breakthrough febrile urinary tract infections.
Materials And Methods:
Children with primary vesicoureteral reflux and detailed voiding cystourethrogram were identified. Ureteral diameter ratio was computed by measuring largest ureteral diameter within the pelvis and dividing by the distance between L1 and L3 vertebral bodies. Demographics, vesicoureteral reflux grade, laterality, presence/absence of bladder-bowel dysfunction, and ureteral diameter ratio were tested in univariate and multivariable analyses. Primary outcome was breakthrough febrile urinary tract infections.
Results:
We analyzed 112 girls and 28 boys with a mean ± SD age of 2.5 ± 2.3 years at diagnosis. Vesicoureteral reflux was grade 1 to 2 in 64 patients (45.7%), grade 3 in 50 (35.7%), grade 4 in 16 (11.4%) and grade 5 in 10 (7.2%). Mean ± SD followup was 3.2 ± 2.7 years. A total of 40 children (28.6%) experienced breakthrough febrile urinary tract infections. Ureteral diameter ratio was significantly greater in children with (0.36) vs without (0.25) breakthrough febrile infections (p = 0.004). Controlling for vesicoureteral reflux grade, every 0.1 U increase in ureteral diameter ratio resulted in 1.7 times increased odds of breakthrough infection (95% CI 1.24 to 2.26, p <0.0001).
Conclusions:
Children with increased distal ureteral diameter ratio are at greater risk for breakthrough febrile urinary tract infections independent of reflux grade. Ureteral diameter ratio provides valuable prognostic information about risk of recurrent pyelonephritis and may assist with clinical decision-making.
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