Urinary tract infection: is there a need for routine renal ultrasonography?

Abstract

Aims: To assess the yield of routine renal ultrasound (RUS) in the management of young children hospitalised with first uncomplicated febrile urinary tract infection (UTI). Methods: All children aged 0-5 years who had been hospitalised over a two year period with first uncomplicated febrile UTI in a medium size institutional regional medical centre were included. Children with known urinary abnormalities and/or who had been treated with antibacterial agents within seven days before admission were excluded. All included children underwent renal ultrasonography during hospitalisation and voiding cystouretrography (VCUG) within 2-6 months. The yield of RUS was measured by its ability to detect renal abnormalities, its sensitivity, specificity, and positive and negative predictive values for detecting vesicoureteral reflux (VUR), and by its impact on UTI management. Results: Of 255 children that were included in the study, 33 children had mild to moderate renal pelvis dilatation on RUS suggesting VUR, of whom only nine had VUR on VCUG. On the other hand, in 36 children with VUR on VCUG the RUS was normal. The sensitivity, specificity, positive predictive value, and negative predictive value of abnormal RUS for detecting VUR were 17.7%, 87.6%, 23.5%, and 83.2% respectively. In none of the patients with abnormal RUS was a change in the management at or following hospitalisation needed. Conclusion: Results show that the yield of RUS to the management of children with first uncomplicated UTI is questionable.

Clinical Profile and Antibiotics Sensitivity in Childhood Urinary Tract Infection at Dhulikhel Hospital

“…18 The author concluded that RUS should only be performed in children in whom complication such as renal parenchyma disease and renal obstruction are suspected based on an unfavorable clinical course or in children in whom VUR has been found in order to look for renal structure abnormalities. In the present study also RUS was done in suspected renal parenchyma disease and in those children whom calculi were suspected.…”

Ultrasound as a Screening Test for Genitourinary Anomalies in Children With UTI

“…Sensitivity has ranged from 18% to 79% and specificity from 41% to 99%, depending on how a "positive" RBUS was defined and what VUR outcome was assessed (eg, any VUR, "dilating VUR," "high-grade VUR"). [6][7][8][9][10][11] Many other groups have reported GU imaging findings among children who have a history of UTI. However, most of these papers have limitations that make it impossible to determine the test characteristics of RBUS; most common is that many studies do not provide sufficient data to directly compare RBUS findings with VCUG findings in individual patients.…”

“…Many studies have similar limitations. 6,7,9,19,24 Other studies have limited generalizability owing to narrow 10,25 or broad [26][27][28] age ranges, or small sample size. 8,[26][27][28] One study looked specifically at the predictive value of ureteral dilation as an isolated finding on RBUS.…”

The point of view of the paediatric nuclear medicine physician Monica A Rossleigh

“…Recent evidence has suggested that imaging work-ups for children with a first uncomplicated UTI may not improve patient care. In one prospective study, 24 renal ultrasonography did not change the management of UTI in any of 255 children younger than five years who were admitted with a first uncomplicated febrile UTI. An earlier systematic review 25 of 63 descriptive studies found no evidence of the impact of routine imaging on clinical outcomes in children with a first UTI.…”