Imaging Tests for Urinary Tract Infections (Children)

Tests | Procedures

What is

Why imaging tests after urinary tract infection?

After an episode of urinary tract infection (UTI), doctor may recommend further tests to look for underlying problems of the urinary tract. These may include ultrasound of the urinary system, a nuclear kidney scan (DMSA scan) and a Micturating Cystogram (X-Ray of the bladder) (MCU). Your child may require one or more of these tests to be done after an episode of UTI.

What is Ultrasound of the urinary tract?

This is a scan performed by a radiologist to look for any structural abnormalities of the kidneys, ureters and bladder that may predispose your child to UTI. This test is safe, it will not cause any pain and has no radiation. This test is usually performed soon after the child has been diagnosed with UTI.

What is Dimercaptosuccinic acid (DMSA) renal scan?

This is a radionuclide scan where a special dye is injected into the blood stream to assess for any scarring of the kidneys. The dye goes round the blood stream and is taken up by the kidneys. A scan is then taken which produces an image of the kidneys. This image will show what the kidneys look like and also reflect how well the kidneys are working and if there are any scars present. A DMSA scan is usually done at least four to six months after the diagnosis of UTI.

What is Micturating Cystourethrogram (MCU)?

This is a test whereby a dye (contrast) is placed into your child’s bladder via a urinary catheter. An X-ray is taken while your child passes urine. This will allow detection of vesicoureteric reflux (VUR).

Vesicoureteric reflux (VUR) is a condition where urine goes back up the ureter (the tube connecting the kidneys to the bladder) instead of going out normally through the urethra (which drains urine from the bladder) only. VUR usually will resolve as the child grows older. The child may need to continue taking the once-nightly dose of preventive antibiotics to prevent further infections, depending on the severity of VUR (Grade 1 to Grade V). Some children with severe VUR and repeated UTIs may require surgery.

Your child will be advised to take a three-day course of antibiotic, starting the day before the MCU and for the following two days. This is required because of an infrequent risk of infection during catheterisation.

If your child is currently taking antibiotics once nightly to prevent urinary tract infections, you will be advised on the appropriate antibiotic and dose to take for the three days. On the fourth day, your child should resume to taking antibiotic once nightly till the next review with the doctor.