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Use of and regional variation in initial CT imaging for kidney stones
Gregory E Tasian1, Jose E Pulido2, Ron Keren3
1Division of Pediatric Urology, Department of Surgery, Division of Urological Surgery, Department of Surgery, Perelman School of Medicine at The University of Pennsylvania, Philadelphia, Pennsylvania; Center for Pediatric Clinical Effectiveness, and tasiang@chop.edu.
Insights
Computed tomography (CT) is frequently the first imaging test for pediatric kidney stones, despite guidelines recommending ultrasound. Significant regional differences in CT use exist across the United States.
Area of Science:
- Pediatric Nephrology
- Radiology
- Health Services Research
Background:
- Nephrolithiasis in children is increasingly diagnosed.
- Imaging guidelines recommend ultrasound as the initial modality for pediatric nephrolithiasis.
- Computed tomography (CT) use in this population has raised concerns due to radiation exposure.
Purpose of the Study:
- To determine the prevalence of initial computed tomography (CT) utilization for children with nephrolithiasis in the United States.
- To identify geographic regions with high CT utilization as the first imaging study for pediatric nephrolithiasis.
Main Methods:
- Cross-sectional study of 9,228 commercially insured children (aged 1-17) with nephrolithiasis from 2003-2011.
- Data sourced from the MarketScan commercial insurance claims database, encompassing over 17 million children nationwide.
- Logistic regression used to analyze initial CT use and identify regional variations.
Main Results:
- Initial CT was utilized in 63% of children, while ultrasound was performed first in 24%.
- State-level initial CT use varied widely, ranging from 41% to 79%.
- Significant regional disparities in CT utilization persisted after adjusting for demographic and clinical factors, with East South Central states showing higher odds and New England states showing lower odds.
Conclusions:
- Initial CT use for pediatric nephrolithiasis is highly prevalent across the US.
- Substantial regional variations in imaging practices for pediatric kidney stones are evident.
- Current imaging practices for pediatric nephrolithiasis do not align with established guidelines recommending initial ultrasound.
Objective:
We sought to determine the prevalence of initial computed tomography (CT) utilization and to identify regions in the United States where CT is highly used as the first imaging study for children with nephrolithiasis.
Methods:
We performed a cross-sectional study in 9228 commercially insured children aged 1 to 17 years with nephrolithiasis who underwent diagnostic imaging in the United States between 2003 and 2011. Data were obtained from MarketScan, a commercial insurance claims database of 17,827,229 children in all 50 states. We determined the prevalence of initial CT use, defined as CT alone or CT performed before ultrasound in the emergency department, inpatient unit, or outpatient clinic, and identified regions of high CT utilization by using logistic regression.
Results:
Sixty-three percent of children underwent initial CT study and 24% had ultrasound performed first. By state, the proportion of children who underwent initial CT ranged from 41% to 79%. Regional variations persisted after adjusting for age, gender, year of presentation, and insurance type. Relative to children living in West South Central states, the highest odds of initial CT utilization were observed for children living in the East South Central US Census division (odds ratio: 1.27; 95% confidence interval: 1.06-1.54). The lowest odds of initial CT were observed for children in the New England states (odds ratio: 0.48; 95% confidence interval: 0.38-0.62).
Conclusions:
Use of CT as the initial imaging study for children with nephrolithiasis is highly prevalent and shows extensive regional variability in the United States. Current imaging practices deviate substantially from recently published guidelines that recommend ultrasound as the initial imaging study.
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