Approximately 7-8% of girls and 2% of boys have a UTI during the first 8 years of life.
Febrile UTIs have highest incidence in both sexes during the first year of life.
Nonfebrile UTIs occur predominantly in girls older than 3 years.
UTIs, after infancy, confined to the bladder with local symptoms, are easily treated.
Fever increases the probability of kidney involvement in childhood UTI, and increases the likelihood of underlying is a nephrourologic abnormalities and a greater risk of renal damage.
Antibiotic treatment of children with febrile UTI has elimiated risk of death, which was as much as 20% in pre-antibiotic era.
Approximately 60% of children with febrile UTIs have evidence of pyelonephritis, and 10-40% will develop permanant renal scarring.
The International Reflux Study in Children reported hypertension and 1.6% of children with vesicoureteral reflux, mainly grade 4, prospectively followed for 10 years (Jodal U et al).
Retrospective studies suggest that renal scarring related to urinary tract infection carries clinically significant risks, with up to 20% rate of chronic kidney disease, 20-40% for hypertension and 10-20% for preeclampsia- These retrospective studies have multiple limitations and biases.
Use of dexamethasone can decrease urinary levels if interleukin-6 and interleukin-8 suggesting a possible rle in preventing scar formation.
Antibiotics are cornerstone of treatment for acute UTI and is important to prevent parenchymal localization of the infection.
The diagnoses of 9854 children who have received renal transplants over 20 years include 16% with hypo-dysplasia, 16% with obstructive uropathy, and 5% with vesicoureteral reflux nephropathy.