Nearly one of every eight children who get a urinary tract infection will end up with scarring on the kidneys as well as an increased risk of kidney failure later in life. For this reason, it is crucial to identify vulnerable children as early as possible, so doctors have used a combination catheter/X-ray test to detect children at greater risk for scarring. In a new study, researchers found three factors when combined were capable of distinguishing these patients. Significantly, these three simple factors — high fever, detection of kidney abnormalities, and discovery of the type of bacteria involved — were as accurate as the status quo test.

Testing For Damage Following A UTI

Urinary tract infection (UTI) symptoms may include a persistent urge to urinate, a burning sensation when urinating, and urine that may appear either cloudy or pink, signifying blood. Of the serious bacterial infections young children are prone to get, UTIs are the most frequent yet this more commonplace status does not render them harmless and for this reason, doctors would run catheter/X-ray tests. Yet, these tests are extremely difficult for children as they required using a catheter to fill the bladder with a special dye, after which the child was instructed to urinate while being X-rayed, so the doctor could observe the flow — not simple! For this reason, Dr. Nader Shaikh, an assistant professor at the University of Pittsburgh and a pediatrician at the Children's Hospital of Pittsburgh, and his colleagues chose to investigate whether a more kid-friendly testing option existed.

So Shaikh and his colleagues began their search by diving into the data. They retrieved and reviewed the medical records of 1,280 children, all under 18 years old when they encountered their first urinary tract infection; all these children had undergone renal scanning. The records showed only about 15 percent of these children suffered kidney scarring in the wake of their UTI. Further analyzing the date, the researchers discovered three factors to be strongly associated with scarring: fever of at least 102 degrees; infection with a bacteria other than E. coli; and ultrasound readings that detected an abnormality in the kidney.

Constructing a model based on these factors, the researchers were able to accurately predict nearly 45 percent of those children who ended up developing kidney scars following a UTI, a rate only five percent less effective than models involving blood tests or the catheter/X-ray examination. Though in Shaikh's words, "the prediction is not perfect,” the best test is always the one that gets done.

Source: Shaikh N, Craig JC, Rovers MM, et al. Identification of Children and Adolescents at Risk for Renal Scarring After a First Urinary Tract InfectionA Meta-analysis With Individual Patient Data. JAMA Pediatrics. 2014.