What Is a Retrograde Pyelogram?

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A retrograde pyelogram is an imaging study of the renal system using X-ray technology, usually with contrast dye. It shows pictures of the structures of the kidneys, bladder, and urinary tract. A retrograde pyelogram helps doctors identify blockages in the urinary tract and may be used to identify causes of blood in the urine (hematuria).

These tests are part of a group of X-ray imaging tests known collectively as pyelography, which has been around since the turn of the 20th century. Retrograde refers to inserting dye through the urethra backward up the urinary tract. The use of iodine-based dyes dates back to the 1950s.

Purpose of a Retrograde Pyelogram

Your doctor might order a retrograde pyelogram to look for possible blockages in the ureters or kidneys. These can be kidney stones, tumors, cysts, blood clots, or even narrowing of the urinary tract (known as strictures). A retrograde pyelogram is less detailed than newer imaging tests for the renal system.

Retrograde pyelography is often used when an intravenous pyelogram (IVP) is unsuccessful in diagnosing the cause of a blockage or if IVP is not possible. Patients with a mild allergy to iodine and contrast dye might not be able to undergo an IVP because the dye is absorbed into the body. Much less of the dye is absorbed in the body during a retrograde pyelogram.

Intravenous pyelography uses a similar dye, but it is injected directly into a vein and travels to the kidneys via the bloodstream. Intravenous pyelography is easier to perform than retrograde pyelography is. An intravenous pyelogram can be obtained by a technician in the X-ray department. A retrograde pyelogram requires a physician to administer the dye in an operating room, possibly under general anesthetic.

Blood in the Urine

Bleeding from the urethra or blood in the urine (hematuria) can be a sign of some sort of trauma, irritation, or blockage in the urinary tract or kidneys. To identify the cause, your doctor might order a collection of tests, including retrograde pyelography or cystoscopy.

Kidney Stones

Hard calcium pebbles that can sometimes build up in the renal system are known as kidney stones. Kidney stones can block the flow of urine and cause it to back up into the kidneys, potentially even overflowing into surrounding tissues.

Diagnosing kidney stones is based on the pain of the patient and by viewing the stones on an X-ray such as intravenous pyelography or retrograde pyelography. Both forms of pyelogram use an iodine-based contrast dye to help the structures of the renal system show up better on the X-ray.

Stent Placement

A stent can be placed in the ureter to help urine flow past a blockage that won't clear or through a narrowed portion of the ureter. A retrograde pyelogram is used to check the placement of the stent. In this case, retrograde pyelography is often used in conjunction with a test called cystoscopy, in which a camera is inserted into the urethra to give the doctor a view of the inside of the renal system. Using the same catheter the camera is inserted through, the doctor is able to inject the dye and to guide the stent into place.

Besides a retrograde pyelogram, your doctor might also order a computed tomography (CT) scan of the kidneys or renal ultrasound. Other, less common tests can also be ordered.

Risks and Contraindications

This is one of the oldest tests used in X-ray imaging. It is very safe to get a retrograde pyelogram. Patients should always be aware of the amount of X-ray radiation you are being exposed to, but the diagnostic benefits of X-rays nearly always outweigh the risks. Patients who are pregnant should discuss the risks of exposing the fetus to X-ray radiation and might want to wait to get the test after delivery if possible.

Allergy to Iodine

The most common complications of retrograde pyelography come from reactions to the iodine-based dye used for the test. Many people are allergic to the dye, which can cause an anaphylactic reaction. Allergic reactions to the dye are less pronounced in retrograde pyelography than in intravenous pyelography.

Sepsis and Urinary Tract Infection

Placement of the catheter that guides the cystoscopy and allows the injection of the dye into the urinary system can introduce a urinary tract infection (UTI). In some cases, an infection can develop into sepsis, a systemic infection. Sepsis is a serious, but very rare complication.

Bladder Perforation and Bleeding

It's common after undergoing a retrograde pyelogram to have a small amount of blood in the urine (hematuria). The urine might appear pink from a small amount of bleeding. Even small amounts of bright red blood are possible. A potentially severe complication that is very rare is a puncture of the bladder wall during the catheter insertion.

Other Complications of Retrograde Pyelography

Patients who are dehydrated might not be able to receive the test. Feces or gas in the bowels could interfere with the test. In most cases, your doctor will ask you to fast for a certain amount of time before the test is performed.

Before the Retrograde Pyelogram

A retrograde pyelogram is usually ordered in advance and your doctor will be able to discuss the test a few days before you get it done. Be sure to ask your doctor if there is anything specific you need to do before the test.

Timing

A retrograde pyelogram usually takes less than 30 minutes to perform. It can take an hour or more to recover afterward, depending on the type of anesthesia used for the test. You should expect to take a total of about two hours including paperwork. Plan on having someone drive you home after the test. Do not expect to have the results of the retrograde pyelogram before you leave.

Location

A retrograde pyelogram can be performed as an outpatient or as part of a hospital stay. Your doctor might perform the test in a hospital operating room or in an outpatient clinic, depending on the type of anesthesia used.

The room will have a table with stirrups and an X-ray machine. You will be asked to undress and lie down on the table with your feet in the stirrups.

What to Wear

During the test, you will have to undress completely. Wear something comfortable and easy to remove. After retrograde pyelography, you could be a little groggy when getting dressed again, so don't wear anything complicated.

Food and Drink

Usually, your doctor will want you to fast before getting a retrograde pyelogram. You will want to be well hydrated. In some cases, you might be asked to take a stool softener and might even need an enema before the test.

During a Retrograde Pyelogram

The exact process of the test will vary depending on your condition and how your doctor likes to do the procedure. It will also depend on the type of anesthesia used.

Pre-Test

You will be asked to undress and get into a gown. You'll receive an intravenous (IV) line in your arm or hand. You'll be asked to lie on the X-ray table with your feet in stirrups. The doctor or another staff member will administer a sedative or anesthesia through the IV line.

Throughout the Test

You will most likely not remember the actual test due to the anesthesia. During this part, which could take as little as five minutes and no more than 30 minutes, you will be sedated. The doctor will place a catheter in your urethra and inject the dye. X-rays will be taken from various directions and then the catheter will be removed.

Post-Test

After the test is complete, you will be moved to a recovery area and monitored until the anesthesia wears off. It could take more than an hour for the sedative to wear off enough for you to leave. You will probably receive an antibiotic and possibly something for pain. Discomfort after the test should be minimal, but there will be some soreness and possibly burning during urination.

After the Retrograde Pyelogram

Once the test is complete, you will likely be given antibiotics and possibly sent home with pain medication. Urine output will be monitored before you are released from the test site and your doctor may ask you to continue to measure your urine output for a few days. This usually means urinating into a graduated container and recording the amount.

Managing Side Effects

Your doctor might suggest over-the-counter pain control. If so, only take what the doctor recommends. Some over-the-counter medications, such as aspirin, can encourage bleeding and your doctor may want you to avoid those.

It's common to have pink-tinged urine after a retrograde pyelogram or cystoscopy. If you have bright red bleeding from your urethra, tell your doctor. You should also call your doctor if you have fever, chills, difficulty urinating, redness or swelling around the opening of the urethra, or any discharge other than urine.

Interpreting Results

This is an imaging test that either shows normal urine flow or not. Retrograde pyelography shows the flow of the dye through the urinary tract on an X-ray. If the dye is seen flowing freely through the entire renal system, the test result is negative or normal.

If the dye appears to be blocked and can't flow through the system properly, the result is considered to be positive, which means your doctor found something abnormal and it might require further study.

Follow-up

The X-rays need to be interpreted by a radiologist and that could take a few hours. Usually, the results of a retrograde pyelogram will be in your doctor's hands on the same day the test was performed. Depending on what time your doctor gets the results, you could receive the results on the same day as well.

Depending on the reason your doctor ordered the test, the result could lead to more tests. If, for example, your test was ordered for blood in the urine and it comes back normal, your doctor will need to do further testing to figure out where the blood is coming from.

If the retrograde pyelogram is abnormal, your doctor might want to see a CT scan for more detail. Discuss the results with your doctor to better understand what they mean to him and how that will affect your care plan going forward.

Your doctor might find that the results indicate something blocking your urinary tract that is consistent with kidney stones or a stricture.

Other Considerations

Discuss the results with your doctor and do not be afraid to ask questions. It is important for you to understand what the results mean to you and to your doctor.

If you want a second opinion, you can get the images from your doctor and have them interpreted by another radiologist. Unless that radiologist doesn't feel the images are adequate, you shouldn't need to repeat the procedure.

A Word From Verywell

Retrograde pyelography has been around for almost a century. This is a tried-and-true test with a long history. It's safe and effective. Make sure you know what your doctor is trying to achieve with this test and ask her to explain the results to you. These are pictures, so your doctor should be able to share and explain the images to you.

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