A common diagnosis among infants and children; if missed, can lead to renal scarring, hypertension, and end-stage renal disease.
Non-specific signs and symptoms may herald UTI, and practitioners should have a high index of suspicion in a febrile infant.
An appropriately obtained urine specimen can confirm the diagnosis and pathogen; urine culture and antimicrobial susceptibility testing will define the appropriate antibiotic for treatment.
Of children <6 years of age with first-time UTI, 25% have vesicoureteral reflux (VUR) and, of those, 25% have significant VUR (grade IV or V), placing them at risk for renal scarring.
Infection can recur in young infants and those with voiding dysfunction in the absence of urinary reflux.
Paediatric urinary tract infection (UTI) is defined as a common bacterial infection involving the lower urinary tract (cystitis), the upper urinary tract (pyelonephritis), or both, causing illness in children. Recognising and treating these infections promptly and accurately is important. UTI is associated with pyelonephritis, which has potential sequelae, including renal scarring. Untreated UTI can also lead to hypertension and end-stage renal disease.
Asymptomatic bacteriuria is the presence of bacteria in urine obtained in asymptomatic children (usually girls) on routine screening or incidentally during other investigations. Antibiotic treatment does not seem to help eliminate the bacteria, reduce recurrence, or prevent kidney damage. 
Interim Division Chief
The Children's Hospital at Montefiore
Associate Professor of Pediatrics
Albert Einstein College of Medicine
BG declares that she has no competing interests.
Dr Beatrice Goilav would like to gratefully acknowledge Dr Frederick Kaskel, Dr Mary Anne Jackson, and Dr Rene VanDeVoorde, previous contributors to this topic. FK, MAJ, and RV declare that they have no competing interests.
Associate Professor of Pediatrics and Family Medicine
Department of Pediatrics
Hasbro Children's Hospital
RR declares that he has no competing interests.
Professor of Family Medicine and Chairman of the Department of Family Medicine
University of Texas Health Sciences Center
RV declares that he has no competing interests.
Cincinnati Children's Hospital Medical Center
EJ declares that she has no competing interests.
Staff Specialist Paediatrician
Children’s Hospital at Westmead
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