Vesicoureteral Reflux (VUR) | Testing and Diagnosis

How is vesicoureteral reflux diagnosed?

Vesicoureteral reflux (VUR) can only be diagnosed by a test called a cystogram, in which a catheter is placed through the urethra into the bladder, and the bladder is filled with fluid. This procedure allows doctors to see the reverse flow of urine toward the kidney. There are two types of cystograms:

  • voiding cystourethrogram (VCUG): an x-ray test that examines your child’s urinary tract. The bladder is filled with contrast using a catheter, and x-ray pictures are taken. The images show if there is any reverse flow of urine into the ureters and kidneys.
  • radionuclide cystogram (RNC): this test is performed similarly to a VCUG with a catheter placed in the urethra and bladder, except a different fluid is used to highlight your child’s urinary tract.

A cystogram is most commonly done in a child who has had a UTI but may also be performed in infants who have hydronephrosis (fluid in the kidneys) — a condition detected by ultrasound before birth.

There are other tests that are sometimes performed in children with VUR including:

If a child is suspected of having a urinary tract infection (UTI), the urine needs to be sampled using special techniques to avoid contamination and false test results. For younger children and infants, this usually means passing a catheter into the bladder to obtain a urine sample. In some cases, a bag will be placed on the child to collect urine, although this method has a high rate of false results. In older, toilet-trained children, the child can urinate into a cup.