Ureteropelvic junction (UPJ) obstruction happens when there is a blockage in part of your urinary tract. It is most common in children and often congenital (present at birth). When a blockage occurs at the UPJ, it can reduce the flow of urine down your ureter and increase pressure inside the kidney, impairing kidney function over time.
UPMC urologists provide expert diagnosis and treatment for UPJ obstruction, offering minimally invasive treatment using endoscopic, laparoscopic, or traditional surgical techniques.
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What Is UPJ Obstruction?
Ureteropelvic junction (UPJ) obstruction happens when there is a blockage in part of your urinary tract. It is most common in children and is often present at birth (congenital).
Urine is formed in your two kidneys, which are waste-filtering organs located in your mid-back, just below your rib cage. The ureteropelvic junction is the area where your ureter — the tube through which urine flows from your kidney to your bladder — connects to the renal pelvis of your kidney, where urine is stored after it is produced.
When a blockage occurs at this junction, it can decrease the flow of urine down the ureter and cause increased pressure inside your kidney. This increased pressure can impair kidney function over time.
What are the types of UPJ obstruction?
There are three types of UPJ obstruction, including:
- Extrinsic UPJ obstruction — Happens when abnormal blood vessels, scar tissue, tumors, or a misshapen kidney compress the ureter.
- Intrinsic UPJ obstruction — Caused by problems with the ureter itself, such as narrowing, a kink or fold, abnormal blood vessels, or ureteral polyps.
- Secondary UPM obstruction — Caused by another condition, such as kidney stones, trauma to the kidney or ureter, or a previous surgery.
How common is UPJ obstruction?
UPJ obstruction mostly occurs in children. It affects about 1 in 1,500 children and is the most common cause of urinary blockages in children. It is rare in adults.
What causes UPJ obstruction?
The most common cause of UPJ obstruction is congenital, meaning a person is born with the obstruction and develops symptoms over time. UPJ obstruction can often be diagnosed prenatally through an ultrasound.
Other causes of UPJ obstruction in adults include:
- Age-related changes in body shape.
- Infection, such as an upper urinary tract infection (UTI).
- Injury to the area.
- Stone disease.
UPJ obstruction risk factors
Children are at higher risk of UPJ obstruction when compared to adults. It is twice as common in men as in women.
Other risk factors include:
- A history of UTIs.
- Family history of UPJ obstruction.
- Having kidney stones.
- Previous surgery in the area.
Complications of UPJ obstruction
Left undiagnosed or untreated, UPJ obstruction can cause complications, including:
- Kidney failure.
- Kidney stones.
- Recurrent UTIs.
How can I prevent UPJ obstruction?
There is nothing you can do to prevent UPJ obstruction that is present at birth. However, adults can reduce their risk of UPJ obstruction by avoiding trauma to their kidneys and getting fast treatment for kidney stones and UTIs.
What Are the Signs and Symptoms of UPJ Obstruction?
Symptoms of UPJ obstruction may include:
- A lump in the abdomen.
- Blood in the urine.
- High with a UTI.
- Intermittent side or back pain.
- Kidney stones.
- Nausea and vomiting.
When should I see a doctor about my UPJ obstruction symptoms?
If you or your child has symptoms of UPJ obstruction, you should see your doctor right away. A fast diagnosis and early treatment can prevent serious complications.
How Do You Diagnose UPJ Obstruction?
Your doctor may suspect UPJ obstruction based on your symptoms and a physical exam.
What to expect during your visit
If your doctor suspects UPJ obstruction, they will:
- Ask about your symptoms.
- Perform a physical exam.
- Order other tests.
- Review your health history and medications.
Tests to diagnose UPJ obstruction
Tests to diagnose UPJ obstruction include:
Blood and urine tests
- Blood urea nitrogen (BUN) — Shows how well your kidneys are filtering urea nitrogen, a waste product, from your blood.
- Creatinine clearance — A comparison of creatinine levels in your blood and your 24-hour urine sample to determine how much creatinine has traveled from your blood to your urine.
- Electrolyte panel — Checks levels of electrolytes in your blood.
Imaging tests
- CT scan — A test that creates images of your body's organs, bones, and tissues. In some cases, IV contrast dye will be used to highlight parts of your urinary tract on the CT images.
- Ultrasound — Uses sound waves to create images of your organs to check for problems. UPJ obstruction can often be diagnosed during pregnancy after an ultrasound exam.
UPJ obstruction prognosis
Fast diagnosis and early treatment of UPJ obstruction can reduce your risk of long-term kidney damage. In some cases, UPJ obstruction in children improves on its own. However, most children and adults who need surgical treatment experience good long-term outcomes.
How Do You Treat UPJ Obstruction?
The goals of UPJ obstruction treatment are to correct the blockage, restore the normal flow of urine, and prevent permanent kidney damage.
Treatment options may include:
Endoscopic procedures for UPJ obstruction
Your surgeon will insert an instrument called an endoscope — a flexible tube with a light and a camera at the end — through your urethra and bladder and into your ureter. Your surgeon will use small surgical instruments to remove the blockage from inside your ureter.
Laparoscopic pyeloplasty for UPJ obstruction
UPMC specializes in laparoscopic pyeloplasty, a minimally invasive surgical procedure that involves inserting a laparoscope (a slim tube with a video camera mounted on the end) into a small incision under your ribcage. While viewing the surgical area on a TV monitor, your surgeon will insert instruments through other small incisions to repair the obstruction.
Compared to open surgery, laparoscopic pyeloplasty results in reduced postoperative pain, faster recovery, and minimal scarring at the incision sites.
Traditional open pyeloplasty surgery for UPJ obstruction
During a pyeloplasty procedure, your surgeon will remove scar tissue and reconnect your ureter to another part of your kidney.
Why Choose UPMC for UPJ Obstruction Care?
When you choose UPMC for UPJ obstruction care, you will receive:
- Access to world-class urology expertise — Our world-renowned experts treat the full spectrum of urinary tract conditions using the latest diagnostic and treatment techniques.
- A full range of treatment options — We offer endoscopic, minimally invasive, and traditional surgical treatments, depending on your condition and needs.
- Multidisciplinary care — We partner with kidney experts, pediatricians, and other specialists to provide comprehensive treatment.
