Children who have a recurrent febrile urinary tract infection (UTI) have a substantially higher risk of renal scarring than those who experience a single febrile UTI, according to investigators.
In a study of 345 children, the incidence of renal scarring increased from 2.8% of children with a single febrile UTI to 25.7% and 28.6% among those who had 2 and 3 or more febrile UTIs, respectively, Nader Saikh, MD, MPH, and colleagues from the Children’s Hospital of Pittsburgh, University of Pittsburgh Medical Center, reported in JAMA Pediatrics. Compared with patients who had a single febrile UTI, those had 2 febrile UTIs and 3 or more febrile UTIs had significant 11.8 times and 13.7 times increased odds of renal scarring, respectively.
“Although the proportion of children with UTIs who have febrile recurrences is relatively small, the risk of renal scarring for those who do is substantially higher,” Dr Saikh’s team concluded. “This finding suggests that research should focus on the identification of biomarkers that could noninvasively identify children at risk for subsequent febrile infections. More research is also needed to understand the molecular basis of the increased risk of renal scarring in children with recurrent febrile UTIs.”
The study included 345 children: 221 with and 124 without vesicoureteral reflux. Of the 345 children, 50 had no febrile UTI (they had an index UTI not accompanied by fever and had no subsequent febrile UTIs) and 246, 35, 13, and 1 had 1, 2, 3, and 4 febrile UTIs, respectively, according to the investigators.
“To our knowledge, this is the largest report on the incidence of renal scarring in children with no febrile UTIs, none of whom developed renal scarring,” they authors wrote. “These data support the notion that children with afebrile UTIs are at very low risk of developing renal scarring, and thus their UTIs could be managed less aggressively.”
The investigators defined renal scarring as decreased uptake of tracer associated with the loss of contours or cortical thinning on a technetium 99m dimercaptosuccinic acid (DMSA) renal scan performed at study exit or at about 4 months following the last febrile UTI.
Shaikh N, Haralam HA, Kurs-Lasky M, Hoberman A. Association of renal scarring with number of febrile urinary tract infections in children. JAMA Pediatr. 2019.