Retrograde Pyelography - Indications, Contraindications, Procedure, and Complications

Introduction:

The urinary system contains organs that are designed to perform their specific functions. The kidneys filter the blood, form urine, and maintain fluid and electrolyte levels in the body. The ureters are tube-like structures that carry urine from the kidneys to the urinary bladder. The bladder stores the urine temporarily, and the urethra carries the urine outside the body. This is how the urinary system eliminates waste products from the body. However, certain conditions affect the urinary system and interfere with normal urine flow. Such conditions are diagnosed either by laboratory tests or imaging tests. Imaging tests are usually performed to confirm the diagnosis; one such test is retrograde pyelography. A dye is injected into the urinary tract, and X-rays are taken as it flows through the body. Since the direction of the flow of dye is opposite to the direction of urine flow, it is known as retrograde.

What Are the Indications of Retrograde Pyelography?

Retrograde pyelography helps to detect problems in the urinary system, like kidney stones, tumors, and hematuria. It also helps in the placement of a ureteral stent after the surgery. The indications of retrograde pyelography have been described below:

1. Kidney Tumor - A tumor is a mass formed due to uncontrolled cell growth. X-rays and retrograde pyelography help to detect these tumors.

2. Ureteral Stricture - It is a condition in which the ureters become narrow due to ureteropelvic junction obstruction. The urine flow is restricted, and the patient experiences pain and difficulty while urinating. Retrograde pyelography helps to know the length of the ureteral stricture so that the treatment can proceed accordingly.

3. Hematuria - Hematuria is one of the symptoms of urinary tract diseases. Retrograde pyelography helps to know the exact disease of the urinary system that might be causing hematuria.

4. Placement of Stent - A stent is a tube inserted into the urethra after the surgery to facilitate the drainage of urine. In retrograde pyelography, a dye is inserted into the urinary system. This dye outlines the ureters and the kidneys so that the stent can be placed at the correct location.

5. Failure of Intravenous Pyelography - In intravenous pyelography, the dye needs to be injected into the body through the veins. As a result, most of it gets absorbed in the body, and the patients allergic to it refrain from the procedure. However, in retrograde pyelography, the dye is injected through the urethra, so the chances of absorption are significantly less.

What Are the Contraindications of Retrograde Pyelography?

There are no absolute contraindications of retrograde pyelography. However, it is relatively contraindicated in the following situations:

• Iodine Allergy - Retrograde pyelography uses an iodine-based dye to produce images of the internal organs. Patients allergic to iodine must inform the doctor before undergoing the procedure. This is because anaphylaxis might occur if iodine enters the bloodstream.

• Infections and Sepsis - Sepsis is the most severe complication of urinary tract infection. If the catheter is inserted for retrograde pyelography in such patients, the risk of sepsis increases as the bacteria can travel through the catheter.

• Dehydrated Person - If the person is extremely dehydrated, the presence of feces and gas in the intestine can interfere with the test results.

How Does the Patient Prepare for a Retrograde Pyelogram?

The patient must take note of the following things before the procedure:

• The patient will be thoroughly explained the risks and benefits of the procedure. If he feels that he can undergo the procedure, he must sign the consent form.

• The patient should inform the doctor in advance about the medications or other herbal supplements he is taking. Sometimes the doctor might ask the patient to stop taking certain drugs like anticoagulants.

• A medication known as a laxative is usually given before the procedure to allow bowel movement.

• The procedure is performed under general anesthesia and takes time, so the patient will be unable to return to work the same day.

• Some antibiotics will be administered before the surgery so that there is no infection in the patient’s blood. The antibiotics most commonly administered before the surgery can be cephalosporins (usually first or second generation) or Amoxicillin and Clavulanic acid.

• Before the commencement of surgery, general anesthesia will be administered to the patient so that he falls asleep and the surgery is carried out smoothly without any pain or inconvenience.

What Happens During the Procedure?

Retrograde pyelography can be done at the hospital or the radiology center. The steps of the procedure are listed below:

• Ask the patient to remove all the objects or clothes that might hinder the procedure.

• The patient is asked to lie straight, and his feet are placed in flaps called stirrups.

• An instrument known as the endoscope is inserted into the urethra. It has a light and a camera attached to it.

• The endoscope is pushed slowly through the urethra into the urinary bladder. It helps to visualize the bladder.

• After the bladder has been located, a tube known as a catheter is inserted into one or both ureters through the urethra.

• Once the catheter is in place, a dye is injected through it.

• X-rays are taken from different angulations as the dye flows through the urinary tract.

• When the X-rays have been taken, the catheter and the endoscope are removed slowly.

What Happens After the Procedure?

The patient will be taken to the recovery ward after the procedure to monitor his vitals, including respiratory rate, pulse, temperature, and oxygen. Finally, the doctor checks if the patient has the following symptoms:

1. Fever.

2. Swelling in the urogenital tract.

3. Presence of blood in the urogenital tract.

4. Presence of severe pain.

5. Difficulty in urinating.

What Are the Complications of Retrograde Pyelography?

Retrograde pyelography is a simple procedure, so the patient rarely experiences any complications. However, the following complications might be noted:

• Sepsis, the severest complication of urinary tract infection, occurs if the bacteria travel through the catheter to the bloodstream and infect it. The procedure should not be performed in patients suffering from urinary tract infections.

• Urinary bladder tear and puncture after the catheter insertion is commonly seen. If this happens, bleeding occurs, and the patient notices a large amount of blood in the urine.

• The risk of severe bleeding increases if the urinary opening gets damaged due to the catheter.

• Nausea, vomiting, and allergic reactions after the procedure affect the patient's general health.

Conclusion:

Retrograde pyelography is an imaging technique used to diagnose problems in the urinary system. A dye is injected into the body with the help of a catheter, and images of the urinary tract are obtained. It is used to detect stones, tumors, ureteral strictures, and the causes of ureteropelvic junction obstruction. This test is preferred by the patient compared to an intravenous pyelogram because of the allergic reactions. The dye is injected into the body directly in an intravenous pyelogram, so the risk of anaphylaxis increases. However, the dye is injected through the ureters in retrograde pyelography, so the risk of allergic reactions is negligible. The patient need not worry about the procedure as there are hardly any side effects. However, before undergoing the procedure, the patient must understand it completely and know about its benefits and risks. Retrograde pyelography is a very effective procedure and helps diagnose urinary tract problems.