Renal Ultrasound for Urinary Tract Infections in Children: Is It Always Necessary?
In children with uncomplicated urinary tract infections, renal ultrasound contributes little to diagnosis or management.
Urinary tract infections are a common medical condition in children, but they can sometimes serve as a marker of underlying anatomic and functional abnormalities. These abnormalities need to be identified and treated to prevent future infections and long-term damage to the kidneys.
To diagnose potential urinary tract abnormalities, the American Academy of Pediatrics recommends children with UTIs can be imaged with three modalities: voiding cystourethrogram (VCUG), radionuclide kidney imaging and renal ultrasound.
Renal ultrasound remains the most recommended imaging method, as it is noninvasive and inexpensive, and does not expose children to radiation. However, it mainly detects abnormalities in the upper urinary tract. VCUG is better at detecting abnormalities of the lower urinary tract, primarily vesicoureteral reflux (VUR), a condition in which urine flows backward from the bladder to one or both ureters and sometimes to the kidneys.
In a new study, researchers assessed the role of renal ultrasound in the management of children hospitalized with a UTI. They found that the sensitivity of renal ultrasound for detecting VUR was 21 percent and the method’s specificity was 87 percent.
The results support other studies showing that renal ultrasound is not a reliable screening tool for VUR. The researchers conclude that, especially in children under 5 years old, renal ultrasound findings are of little diagnostic value and have no influence on clinical management. They recommend that renal ultrasound should be performed only in children in whom complications such as renal obstruction or abscess are suspected or in children in whom VUR has been found by other imaging means.