Alternative Names pelvic ureteric junction obstruction, UPJ Obstruction, pelvo-uretero obstruction
Definition The renal pelvis is the structure that drains urine from the kidneys. The tube that carries the urine from the renal pelvis into the bladder is called the ureter. The narrow area where these two structures meet is called the pelvic ureteric junction (PUJ). A blockage in the PUJ can inhibit the flow of urine.
What is going on in the body? Blockage of the PUJ can be present from birth. It is a common urinary tract abnormality. Most of the time the problem appears in childhood. In some people, however, symptoms may not show up until after puberty. Obstruction can also result from a kidney stone lodged in the area or from injury.
In between 10 and 40 percent of cases, PUJ obstruction occurs on both sides of the body. Twenty to forty percent of children with this condition have a backflow of urine into the kidney.
What are the signs and symptoms of the condition? Symptoms of PUJ in children include:
external trauma, or injury to the body over the kidney area
injury during endoscopy or surgical procedures
There is some suspicion that the problem can be inherited. However, this has not been proven conclusively.
What can be done to prevent the condition? There is no known prevention for this condition. However, if PUJ is due to a kidney stone, it may be helpful for a person to drink plenty of fluids.
How is the condition diagnosed? The doctor will suspect a PUJ obstruction if the renal pelvis and kidneys are dilated. This dilation is known as hydronephrosis, and can be detected with a pregnancy ultrasound. It should be confirmed with another ultrasound after the baby is born.
Other diagnostic tests include:
Doppler ultrasound to measure the blood flow to the kidney
renal scintigraphy, involves the injection of radio-nuclide tracer into a vein in the arm. The images produced from technique are helpful in assessing kidney function.
What are the long-term effects of the condition? Chronic obstruction can lead to the gradual loss of kidney function. Urinary tract infections are common with PUJ. They can be serious when this condition is present. Also, kidney stones are prone to form in the urine that collects in the urinary tract when there is a blockage.
What are the risks to others? There are no risks to others, as PUJ obstruction is not contagious.
What are the treatments for the condition? If a PUJ obstruction is clearly present and is affecting kidney function, surgery is needed to repair it. This operation involves cutting the ureter to remove the blockage, then reattaching it to the renal pelvis. This procedure can be done through an endoscope or with open surgery.
Endoscopic techniques are frequently performed with adults. They are less commonly used with children. They carry a slightly lower success rate than open surgery. However, there are few complications and the person is able to recover more quickly.
What are the side effects of the treatments? There are possible side effects with any surgery. These include bleeding, infection, and allergic reaction to the anaesthesia. Stents and tubes placed in the urinary tract following surgery may cause discomfort, and an increased risk for infection. The person may also need to urinate frequently.
What happens after treatment for the condition? Complications of surgical repair of PUJ obstruction can include:
bleeding
infection
damage to the kidney or ureter
How is the condition monitored? Follow up visits with the surgeon will be necessary if surgery has been performed. Any new or worsening symptoms should be reported to the doctor.
Author: Stuart Wolf, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
