Imaging studies after first episode of urinary tract infection (UTI)

Ultrasound kidneys is recommended in all cases with UTI irrespective of age. 

Dimercaptosuccinic acid scan (DMSA) should only be done after 3 to 4 months of treatment to detect renal scarring in children between 1-5 year of age with first UTI. In children older than 5 years it is recommended only if ultrasound kidneys is abnormal. It is not recommended for diagnosing acute pyelonephritis to avoid unnecessary radiation exposure. 

Micturition cystourethrography (MCU) /Voiding cystourethrography (VCUG) can be done any time during or after treatment, under antibiotic coverage. It is indicated if age of the child is less than 1 year or  children more than one  year of age with abnormal ultrasound and/or DMSA scan.

Any child with recurrent UTI or age less than 1 year with first episode of UTI need all the three imaging studies, ultrasound kidneys, DMSA scan and MCU/VCUG.