UTI occurs in 8% of female and 2% of male children, most often during the first 2 years of life. They are usually discovered because of high fever (greater than 101⁰), although an older child may have pain during urination without fever.
The greatest concern from UTI with fever is the risk for damage to the kidneys. Fortunately this occurs in less than 20% of cases, usually after more than 1 infection.
In the past, 2 radiologic studies were routinely done in children after febrile UTI, an ultrasound of the kidneys, and an x-ray test of the bladder (VCUG) done to detect backwards flow of urine to the kidneys – called “reflux”.
Today the AAP recommends kidney ultrasound without VCUG after the first UTI with fever in children less than 2 years old. We follow that approach for most patients. We also agree that most children with reflux may not need treatment, since few will develop repeated febrile UTIs or kidney damage. The best available test for kidney damage is the DMSA scan, which we use in some cases to help decide which children need a VCUG or treatment for reflux.