After the patient's bladder is filled with a liquid called contrast material, an X-ray machine sends beams of radiation through the abdomen and pelvis, and images are recorded on special film or a computer. These images help doctors see problems in parts of the urinary system, including the bladder, urethra (the tube connecting the bladder with the outside of the body), and the ureters (the tubes connecting the kidneys to the bladder).
A radiologist takes the X-rays using a technique called fluoroscopy. While the contrast material fills your child's bladder, and then while your child empties the bladder, the radiologist watches an onscreen X-ray video of the liquid moving through the urinary system and a series of X-ray films is recorded.
In general, X-rays are very safe. Although there is some risk to the body with any exposure to radiation, the amount used in a VCUG is small and not considered dangerous. It's important to know that Nemours radiologists use the minimum amount of radiation required to perform the study properly.
What does a VCUG show?
A VCUG can show whether the urine is moving in the right direction. Normally, urine flows from the kidneys down to the bladder through the ureters. When urine goes back up toward the kidneys, it's called vesicoureteral reflux (VUR), which a VCUG can detect. Sometimes VUR only occurs while urinating (voiding), which is why the VCUG includes taking X-ray images while the bladder is being emptied.
At times, fear, anxiety, and developmental stage of a child contribute to his or her ability to cooperate with medical procedures. Pediatric procedural sedation can be used to decrease discomfort and anxiety for your child.
Sedation is available for VCUG and a separate sedation appointment would be needed to be scheduled prior to the study.
Providing sedation means a child is given medicine to make the child more relaxed. When a child is sedated, he or she may better tolerate a medical procedure and will probably not remember it.
The sedation team aims for mild to moderate sedation, meaning that your child will be relaxed, but awake enough to answer questions and to sense a full bladder. Typical sedatives for this procedure include midazolam (Versed), given orally or as a nasal spray, or nitrous oxide (“laughing gas”) given with a mask. This procedure takes about 10 minutes for catheter placement and bladder filling, and another few minutes for the child to urinate.
detect overactivity or underactivity in the parathyroid glands (glands in the neck that make hormones that help control the level of calcium in the blood)
monitor disorders of the kidney and diseases of calcium metabolism
The test results also may point to digestive disorders that harm the small intestine's ability to absorb nutrients. The urine calcium test is usually used in combination with other tests to make a specific diagnosis.
The doctor might prescribe a special diet with high or low levels of calcium for a few days before the test. Your child might need to temporarily stop taking specific drugs, such as antacids, that affect calcium levels in the urine.
Collecting the specimen should only take a few minutes. Your child will be asked to pee into a clean sample cup in the doctor's office. If your child isn't potty trained and can't urinate into a cup, a small catheter may need to be inserted into the bladder to get the urine specimen.
Alternatively, a urine collection bag with adhesive tape on one end may be used to collect a sample from an infant. You'll clean your baby's genital area and then arrange the bag around the urinary opening. Once the bag is in place, secure it with the attached tape. You can then put a diaper on your baby. Check your baby's collection bag and remove it after your child has urinated, usually within an hour.
After you bring the sample to the lab, technicians will analyze it for calcium content.
What to Expect
Because the test involves normal urination, there shouldn't be any discomfort as long as your child can provide a urine specimen.
Getting the Results
The results of the urine calcium test are usually available in 1-2 days. Your doctor will go over the results with you and explain what they mean. If abnormalities are found, your doctor may may want to do further tests to make a specific diagnosis.
Infants may occasionally experience skin irritation from the adhesive tape on the collection bag. If a catheter is used to obtain the urine, it may cause temporary discomfort. If you have any questions or concerns about this procedure, talk to your doctor.
Helping Your Child
Urine collections are usually painless. Explaining how the test will be conducted and why it's being done can help ease any fear. Make sure your child understands that there should be no foreign matter, such as toilet paper or hair, in the sample.
If You Have Questions
If you have questions about the urine calcium test, speak with your doctor.
Reviewed by: Yamini Durani, MD
Date reviewed: April 28, 2017