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Risk Factors for Recurrent Urinary Tract Infection and Renal Scarring
Ron Keren1, Nader Shaikh2, Hans Pohl3
1Division of General Pediatrics, Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Departments of Pediatrics and Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; keren@email.chop.edu.
Insights
Vesicoureteral reflux (VUR) and bladder/bowel dysfunction (BBD) significantly increase the risk of recurrent urinary tract infections (UTIs) in children. Combined VUR and BBD present the highest risk, highlighting the need for targeted prevention strategies.
Area of Science:
- Pediatric Nephrology
- Infectious Diseases
- Urology
Background:
- Recurrent urinary tract infections (UTIs) in children can lead to renal scarring and long-term complications.
- Identifying risk factors for recurrent UTIs and renal scarring is crucial for effective management.
Purpose of the Study:
- To determine risk factors for recurrent febrile or symptomatic UTIs (F/SUTIs) and renal scarring in children with a history of UTIs.
- To investigate the combined impact of vesicoureteral reflux (VUR) and bladder and bowel dysfunction (BBD) on recurrent UTI risk.
Main Methods:
- A 2-year prospective cohort study involving 305 children with VUR (placebo group) and 195 children without VUR.
- Primary exposure: VUR. Secondary exposures: BBD, age, and race.
- Outcomes: Recurrent F/SUTI and renal scarring, assessed via clinical evaluation and (99m)Tc-labeled dimercaptosuccinic acid scans.
Main Results:
- Children with VUR had higher 2-year rates of recurrent F/SUTI (25.4% vs 17.3%).
- BBD at baseline (aHR: 2.07) and baseline renal scarring (aHR: 2.88) were associated with increased recurrent F/SUTI risk.
- The highest risk of recurrent F/SUTI (56%) was observed in children with both BBD and VUR. No significant difference in renal scarring rates between VUR and no VUR groups.
Conclusions:
- Vesicoureteral reflux (VUR) and bladder and bowel dysfunction (BBD) are significant risk factors for recurrent UTIs in children.
- The combination of VUR and BBD confers the highest risk for recurrent UTIs.
- Antimicrobial prophylaxis and BBD treatment are recommended strategies for preventing recurrent UTIs in at-risk children.
Objectives:
To identify risk factors for recurrent urinary tract infection (UTI) and renal scarring in children who have had 1 or 2 febrile or symptomatic UTIs and received no antimicrobial prophylaxis.
Methods:
This 2-year, multisite prospective cohort study included 305 children aged 2 to 71 months with vesicoureteral reflux (VUR) receiving placebo in the RIVUR (Randomized Intervention for Vesicoureteral Reflux) study and 195 children with no VUR observed in the CUTIE (Careful Urinary Tract Infection Evaluation) study. Primary exposure was presence of VUR; secondary exposures included bladder and bowel dysfunction (BBD), age, and race. Outcomes were recurrent febrile or symptomatic urinary tract infection (F/SUTI) and renal scarring.
Results:
Children with VUR had higher 2-year rates of recurrent F/SUTI (Kaplan-Meier estimate 25.4% compared with 17.3% for VUR and no VUR, respectively). Other factors associated with recurrent F/SUTI included presence of BBD at baseline (adjusted hazard ratio: 2.07 [95% confidence interval (CI): 1.09-3.93]) and presence of renal scarring on the baseline (99m)Tc-labeled dimercaptosuccinic acid scan (adjusted hazard ratio: 2.88 [95% CI: 1.22-6.80]). Children with BBD and any degree of VUR had the highest risk of recurrent F/SUTI (56%). At the end of the 2-year follow-up period, 8 (5.6%) children in the no VUR group and 24 (10.2%) in the VUR group had renal scars, but the difference was not statistically significant (adjusted odds ratio: 2.05 [95% CI: 0.86-4.87]).
Conclusions:
VUR and BBD are risk factors for recurrent UTI, especially when they appear in combination. Strategies for preventing recurrent UTI include antimicrobial prophylaxis and treatment of BBD.
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