The job of the urinary system is to eliminate waste from the body. The normal urinary system consists of two kidneys, with a tube (ureter) connecting each kidney to the bladder and another tube (urethra) that drains urine from the bladder out of the body. A ureteral obstruction is a blockage that occurs anywhere in this system.
Certain conditions may make you more prone to a ureteral obstruction including conditions present from birth (congenital), a tendency to make kidney stones or recent cancer surgery.
Duplication of the ureter
This common congenital condition causes two ureters to form on the same kidney. The second ureter can be either completely or partially developed. If either of these ureters does not function properly, urine can back up into the kidney and cause damage.
This abnormality is a blockage in the connection between the kidney and ureter that stops urine flow and causes the kidney to swell and eventually stop working. This abnormality can be congenital, can develop with normal childhood growth, can result from an injury or scarring, or in rare cases, can develop from a tumor. It is more common among boys. Symptoms of this abnormality can vary from mild to severe so frequent monitoring by your doctor is recommended.
Ureterovesical junction. In this condition, the blockage occurs between the ureter and the bladder, causing urine to back up into the kidneys.
When the ureter is too narrow and does not allow urine to flow normally, a tiny hernia (ureterocele) will develop, usually in the section of the ureter closest to the bladder. This hernia blocks urine flow, causing urine to back up into the kidney, which can damage the kidney.
In this rare condition (also known as circumcaval ureter or postcaval ureter), the ureter twists abnormally and can block the urine flow from the kidney to the bladder.
Intrinsic or extrinsic ureteral obstruction. This condition refers to a blocked ureter by various causes including:
- Ureteral stones
- Severe constipation, which happens primarily in children but also in adults
- Cancerous and noncancerous tumors
- Internal tissue growth such as endometriosis in females
- Long-term swelling of the ureter wall, usually due to diseases such as tuberculosis or schistosomiasis
This rare disorder (also called Ormond disease, retroperitoneal fasciitis or chronic retroperitoneal fibroplasias) occurs when fibrous tissue grows in the area behind the abdomen. The fibers may grow due to cancers or may result from taking certain medicines used to treat migraines. The fibers encircle and block the ureters, causing urine to back up into the kidneys.
Frequently, ureteral obstruction disorders are diagnosed before birth during routine prenatal ultrasounds, which can show details of the developing fetus including the kidneys, ureters and bladder. To diagnose an adult or child, diagnostic tests may include:
- Blood and urine tests. Samples of your blood and urine are tested for infection and the presence of creatinine that signal the kidneys are not working properly.
- Retroperitoneal ultrasound. An ultrasound of the area behind your abdominal organs is performed allowing doctors to view the kidneys and ureters.
- Voiding cystourethrogram. To test for abnormal flow of urine, a small tube (catheter) is inserted through the urethra, dye is injected into your bladder and several X-rays are taken of your kidneys, ureters, bladder and urethra before and during urination.
- Intravenous pyelogram (IVP) or excretory urogram. Dye is injected into a vein in your arm, and X-rays are taken as the contrast moves into your kidneys, ureters and bladder.
- Renal nuclear scan. This test is similar to an IVP, except the dye contains a small amount of radioactive material, which is detected by a special camera. It can evaluate the urinary system, reveal a ureter disorder and view the kidneys for damage caused by a ureteral obstruction.
- Cystoscopy. A small tube with a camera and light is inserted into your urethra or through a small incision. The optical system allows the doctor to see inside the urethra and bladder.
The goal of ureteral obstruction treatment is to remove blockages and repair damage to the ureters and kidneys. Because of the complexity of the urinary system, you may need more than one type of treatment.
A ureteral obstruction disorder causing severe pain may require an immediate procedure to remove urine from your body and temporarily relieve the problems caused by a blockage. The procedures may include:
- A catheter. Inserting a tube through the urethra into the bladder
- A ureteral stent. Inserting a hollow tube inside the ureter to keep it open
- Percutaneous nephrostomy. Inserting a tube through your back to drain the kidney directly
Minimally invasive (laparoscopic) surgery
Minimally invasive surgery is performed with a small, flexible tube (laparoscope) through which surgical instruments are inserted and manipulated. A tiny camera attached to the tube allows doctors to see inside the body.
- Endopyelotomy or laparoscopic pyeloplasty. These procedures are used to correct a blocked or damaged ureter. The surgeon reopens or repairs the ureter and inserts a stent to keep the ureter open. This stent will remain in place for up to six weeks and is removed during an office visit.
With minimally invasive surgery, patients often have shorter hospital stays, less discomfort and bleeding and a shorter recovery period.
Surgical procedures performed through an incision in the abdomen to correct a ureteral obstruction include:
- Heminephrectomy. This surgery removes the damaged part of the kidney caused by the ureteral obstruction.
- Ureterectomy. The surgeon removes all or part of a ureter then reconnects the kidney to the bladder by lowering the kidney and stretching the bladder up or replacing the ureter using other body tissue. The type of repair depends on how much of the ureter is removed.
- Ureteral reimplantation. The dysfunctional section of the ureter is removed and the remaining healthy sections are reconnected and reattached to the bladder.
- Transureteroureterostomy. The surgeon joins one ureter to the other resulting in sustained improvement in long-term renal function.
Ureteral obstructions may occur simultaneously with recurrent, difficult-to-cure urinary tract infections. Antibiotic treatment is necessary for each infection to prevent disease in the bladder or kidneys.