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Published on: July 18, 2017
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Clinically unsuspected pyelonephritis in children younger than 7 years
Boaz Karmazyn1, David S Hains2, Rebeca Santos3
1Department of Radiology and Imaging Sciences, Riley Hospital for Children, Riley Hospital for Children at Indiana University Health, Indiana University School of Medicine, 705 Riley Hospital Dr., Rm 1053, Indianapolis, IN, 46202, USA. Bkarmazy@iu.edu.
Emergency Radiology
|August 16, 2025
Summary
In young children, computed tomography (CT) diagnosed pyelonephritis is often unsuspected and may have negative urine tests. Follow-up imaging is recommended to check for scarring and vesicoureteral reflux (VUR).
Area of Science:
- Pediatric Nephrology
- Diagnostic Imaging
- Infectious Diseases
Background:
- Diagnosis of pyelonephritis in young children presents significant challenges.
- Early and accurate diagnosis is crucial to prevent long-term renal damage.
Purpose of the Study:
- To determine the incidence and characteristics of pyelonephritis diagnosed via computed tomography (CT) in children under 7 years of age.
- To identify cases of CT-diagnosed pyelonephritis that were not clinically suspected.
Main Methods:
- Retrospective analysis of children under 7 years diagnosed with pyelonephritis via CT between 2011 and 2024.
- Review of demographic, clinical, and laboratory data, along with CT scan findings by a pediatric radiologist.
- Statistical analysis using Wilcoxon rank sum and Chi-square tests to compare clinical and imaging findings.
Main Results:
- 51% of CT-diagnosed pyelonephritis cases in children under 7 were clinically unsuspected.
- 16.3% of patients had negative urinalysis results.
- Renal scarring was observed in 23.4% of patients with follow-up imaging, and 80.4% had vesicoureteral reflux (VUR), including high-grade VUR in 50% of those with VUR.
Conclusions:
- CT-diagnosed pyelonephritis in young children frequently occurs without clear clinical suspicion and can be associated with negative urine tests.
- Follow-up ultrasound and voiding cystourethrogram are essential for evaluating renal scarring and VUR, even without a history of urinary tract infection (UTI).
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