What is an antegrade pyelogram?
An antegrade pyelogram is an imaging test to find a blockage (obstruction) in the upper urinary tract. Your urinary tract includes the kidneys, ureters, and bladder. The ureters are the narrow tubes that carry urine from the kidneys to the bladder.
X-rays use a small amount of radiation to create images of your bones and internal organs. An antegrade pyelogram is one type of X-ray.
Fluoroscopy may also be used during this test. It is like an X-ray "movie." Or the radiologist may use ultrasound to guide placement of the needle. These tests can help the radiologist locate the kidneys and ureters.
During the test, the radiologist injects a contrast dye through a needle that is placed through the flank area of your back. The area will be cleansed with sterile material and you will be given a local anesthetic. The radiologist uses X-ray images to watch the contrast dye as it moves from the kidney into the ureter and then to the bladder.
Why might I need an antegrade pyelogram?
You may need an antegrade pyelogram if other imaging tests did not give your primary healthcare provider enough information to make a diagnosis. You may have had a retrograde pyelogram, a similar test that looks at the kidneys and ureters. Or you may have had an intravenous pyelogram. In that test, the contrast dye was injected into a vein instead of into your kidney or ureter.
The antegrade pyelogram can find a blockage in the urinary tract caused by:
- Narrowing of the ureter (stricture)
- Kidney stone
- Blood clot
The radiologist can find the blockage by looking at the X-ray images. The contrast dye will not be able to move or may be delayed through the kidney if you have a blockage.
You may also need this test to assess the kidneys or ureters before or after surgery. If you have a blockage, the surgeon may use a special tube (ureteral stent) to pass the urine around the blockage or place a kidney tube (nephrostomy catheter) to relieve the obstruction.
Your healthcare provider may have other reasons to recommend an antegrade pyelogram.
What are the risks of an antegrade pyelogram?
You may want to ask your healthcare provider about the amount of radiation used during the test. Also ask about the risks as they apply to you.
Consider writing down all X-rays you get, including past scans and X-rays for other health reasons. Show this list to your provider. The risks of radiation exposure may be tied to the number of X-rays you have and the X-ray treatments you have over time.
Tell your healthcare provider if you:
- Are pregnant or think you may be pregnant. Radiation exposure during pregnancy may lead to birth defects.
- Are allergic to or sensitive to any medicines, contrast dye, or iodine. Because contrast dye is used, there is a risk for allergic reaction to the dye.
- Have kidney failure or other kidney problems. In some cases, the contrast dye can cause kidney failure. You are at higher risk for this if you take certain diabetes medicines.
Possible complications of antegrade pyelogram include:
- Formation of a urine-filled cyst (urinoma)
- Blood clots in the nephrostomy tube if used, or clots in the bladder
You may not be able to have this test if you have a blood clotting disorder.
You may have other risks depending on your specific health condition. Be sure to talk with your provider about any concerns you have before the procedure.
How do I get ready for an antegrade pyelogram?
- Your healthcare provider will explain the procedure to you. Ask him or her any questions you have about the procedure.
- You may be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if anything is not clear.
- You'll be asked to not eat or drink liquids (fast) before the procedure. Your healthcare provider will tell you how long to fast. It might be several hours or overnight.
- Tell your provider if you are pregnant or think you may be pregnant.
- Tell your healthcare provider if you are allergic to contrast dye or iodine.
- Tell your healthcare provider if you are sensitive to or are allergic to any medicines, latex, tape, or anesthetic drugs (local and general).
- Tell your provider about all medicines you are taking. This includes prescriptions, over-the-counter medicines, and herbal supplements.
- Tell your healthcare provider if you have had a bleeding disorder. Also tell your provider if you are taking blood-thinning medicine (anticoagulant), aspirin, or other medicines that affect blood clotting. You may need to stop these medicines before the test.
- You may get medicine to help you relax (sedative) during the test. You will need to have someone drive you home afterward.
- You may be given antibiotics before and after the test.
- Follow any other instructions your provider gives you to get ready.
What happens during an antegrade pyelogram?
You may have an antegrade pyelogram as an outpatient or as part of your stay in a hospital. The way the test is done may vary depending on your condition and your healthcare provider's practices.
Generally, an antegrade pyelogram follows this process:
- You will be asked to remove any jewelry or other objects that may get in the way of the test.
- You may be asked to remove clothing. If so, you will be given a gown to wear.
- An intravenous (IV) line will be inserted into your arm or hand.
- You will be asked to lie face down on the X-ray table. The radiology nurse or technician will wipe an area of skin on your lower back with iodine. This will sterilize the area. Sterile drapes will be placed around it.
- The radiologist will inject a local anesthetic to numb the area. Using ultrasound or fluoroscopy, the radiologist will move the needle into the renal pelvis and inject the contrast dye. You may feel mild discomfort during the injection of the local anesthetic. You may also have a brief feeling of warmth from the contrast dye.
- The radiologist will take a series of X-rays as the dye moves through the ureters.
- Once the needle has been inserted, the radiologist may put a thin wire through the needle. This will let him or her put in a thin tube (catheter), a nephrostomy tube, or other devices that are needed.
- The radiologist will remove the needle if you do not need a nephrostomy tube.
- He or she will put a sterile bandage or dressing on the site.
What happens after an antegrade pyelogram?
After the procedure, you will be taken to the recovery room. Medical staff will watch your blood pressure, pulse, and breathing. Once you are alert, you will be taken to your hospital room or sent home.
Your urine will be watched closely to see how much of it you are making and if you have any blood in it. Your urine may be red from even a small amount of blood. This is considered normal. You may be told to keeping looking at your urine output for a day or so once you are home.
You may have pain when you urinate. Take a pain reliever for soreness as recommended by your healthcare provider. Take only the medicines your provider tells you to. Aspirin or certain other pain medicines may raise the risk of bleeding.
Call your healthcare provider right away if any of these happen:
- Fever or chills
- Redness, swelling, or bleeding or other drainage from the insertion site
- Pain around the insertion site gets worse
- You have more blood in your urine
- Difficulty urinating
Your healthcare provider may give you other instructions, depending on your situation.
Before you agree to the test or the procedure make sure you know:
- The name of the test or procedure
- The reason you are having the test or procedure
- What results to expect and what they mean
- The risks and benefits of the test or procedure
- What the possible side effects or complications are
- When and where you are to have the test or procedure
- Who will do the test or procedure and what that person’s qualifications are
- What would happen if you did not have the test or procedure
- Any alternative tests or procedures to think about
- When and how will you get the results
- Who to call after the test or procedure if you have questions or problems
- How much will you have to pay for the test or procedure