Tests and diagnosis

By Mayo Clinic Staff

Laboratory analysis of urine (urinalysis) can reveal whether your child has a UTI. Other tests are necessary to determine the presence of vesicoureteral reflux. They may include:

  • Kidney and bladder ultrasound. Also called sonography, this imaging method uses high-frequency sound waves to produce images of the kidney and bladder. Ultrasound can detect structural abnormalities. This same technology, often used during pregnancy to monitor fetal development, may also reveal swollen kidneys in the fetus, an indication of primary vesicoureteral reflux.
  • Voiding cystourethrogram (VCUG). This test uses X-rays of the bladder when it's full and when it's emptying to detect abnormalities. A thin, flexible tube (catheter) is inserted through the urethra and into the bladder while your child lies on his or her back on an X-ray table. After contrast dye is injected into the bladder through the catheter, your child's bladder is X-rayed in various positions. Then the catheter is removed so that your child can urinate, and more X-rays are taken of the bladder and urethra during urination to see whether the urinary tract is functioning correctly.

    Risks associated with this test include discomfort from the catheter and from having a full bladder, a new urinary tract infection, and possibly, a reaction to the dye in the form of bladder spasms.

  • Nuclear scan. This test, known as radionuclide cystogram, uses a procedure similar to that used for VCUG, except that instead of dye being injected into your child's bladder through the catheter, this test uses a radioactive tracer (radioisotope). The scanner detects the tracer and shows whether the urinary tract is functioning correctly. Risks include discomfort from the catheter and discomfort during urination. Your child's urine may be slightly pink for a day or two after the test.

Grading the condition

Vesicoureteral reflux is graded according to the degree of reflux. In the mildest cases, urine backs up only to the ureter (grade I). The most severe cases involve severe kidney swelling (hydronephrosis) and twisting of the ureter (grade V).

Jul. 16, 2011