August 13, 2019
2 min read

Risk for kidney scarring spikes with two or more febrile UTIs

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

Nader Shaikh

Children with more than one febrile UTI are at a significantly increased risk for kidney scarring, according to findings published in JAMA Pediatrics. Researchers wrote that the risk for scarring increases with each additional febrile infection.

Renal scarring has been called the “most worrisome” and permanent effects of poorly managed UTI in children.

“Understanding the association between the number of episodes of febrile UTI and the risk for renal scarring can help develop evidence-based management strategies for children with this frequently occurring problem,” Nader Shaikh, MD, MPH, an assistant professor of pediatrics at the University of Pittsburgh School of Medicine, and colleagues wrote.

The researchers performed a post hoc analysis of data collected from two previously conducted multicenter prospective studies. The studies — the Randomized Intervention for Children with Vesicoureteral Reflux study, conducted from 2007 to 2013, and the Careful Urinary Tract Infection Evaluation study, conducted from 2008 to 2013 — included a combined 345 children diagnosed with their first UTI without baseline renal abnormalities. Follow-up for recurrent infection took place for 2 years.

Of the children included, 221 had vesicoureteral reflux (VUR). The incidence of renal scarring was 2.8% (95% CI, 1.2% vs. 5.8%) following participants’ first febrile UTI and increased with each additional febrile infection, jumping to 25.7% for two febrile UTIs (95% CI, 12.5%-43.3%) and 28.6% for three or more febrile UTIs (95% CI, 8.4%-58.1%), according to Shaikh and colleagues.

The researchers wrote that after children experienced their first febrile UTI, their odds of renal scarring became 11.8 times higher (95% CI, 4.1-34.4). The odds were 13.7 times higher (95% CI, 3.4-54.4) among children with three or more febrile UTIs.

In a related editorial written by Kenneth B. Roberts, MD, professor emeritus of pediatrics at the University of North Carolina at Chapel Hill, wrote that 14.2% of children who experience one febrile UTI will experience another. He questioned whether it might be possible to identify children at risk for additional infections to prevent renal scarring.

“Bowel and bladder dysfunction (BBD) is clearly a risk factor,” he wrote. “It can be diagnosed by the use of a questionnaire for children aged older than 24 months. Among children not known to have BBD at the time of the first UTI, 37% of girls and 5% of boys can be identified as having BBD within a 2-year follow-up period. Another risk factor is high-grade VUR, which occurs in approximately 5% of infants and young children with a first UTI” and can be identified in most cases through renal-bladder ultrasonography.

Roberts added that children with BBD may reduce the recurrence of UTIs with management of constipation, but those who are too young to be diagnosed with the condition could be recommended dietary changes that could avoid constipation.

Young children with both BBD and VUR face the highest risk, he said. – by Katherine Bortz


Chua M, et al. Can Urol Assoc J. 2018;doi:10.5489/cuaj.4796.

Roberts KB. JAMA Pediatr. 2019;doi:10.1001/jamapediatrics.2019.2509.

Shaikh N, et al. JAMA Pediatr. 2019;doi:10.1001/jamapediatrics.2019.2504.

Disclosures: Roberts reports no relevant financial disclosures. Shaikh reports receiving grants from the National Institute of Diabetes and Digestive and Kidney Diseases while conducting the study. Please see the study for all other authors’ relevant financial disclosures.