Ureteral stricture

Ureteral stricture (Ureteral stricture)

Disease Description (Causes and Symptoms)

• Definition: A condition in which part of the ureter (the tube that carries urine from the kidneys to the bladder) becomes narrowed, obstructing urine flow.
• Causes:
  • Congenital abnormalities (abnormal formation of the ureteral muscles or tube), injury caused by trauma or surgery, infection (especially severe urinary tract infections), urinary stones, radiation therapy, malignant tumors, and others.
• Pathophysiology:
  • Narrowing of the ureter impairs urine drainage, increasing pressure in the ureter and renal pelvis (hydronephrosis), causing recurrent infection and inflammation, and, if prolonged, damage to the renal parenchyma and decreased kidney function.
• Main symptoms:
  • Flank or abdominal pain, fever (when accompanied by infection), pain during urination, hematuria, and recurrent urinary tract infections. In cases of severe obstruction, decreased urine output or symptoms of acute kidney failure may occur.
• Clinical features:
  • Symptoms and management vary depending on the location (distal, middle, or proximal) and length of the stricture and its cause. Some cases are found incidentally without symptoms.

Treatment Methods

• Diagnostic supporting tests (important for treatment decisions)
  • Abdominal and pelvic CT (to assess the structure of the urinary system), renal ultrasound (to determine whether hydronephrosis is present), intravenous pyelography (IVP) or retrograde pyelography/ureterography (to determine the location and length of the stricture), and nuclear medicine renal function testing (to assess split renal function).
• Nonsurgical/endoscopic treatment
  • Ureteral stent (Double-J): Inserted into the ureter to immediately secure a route for urine drainage. It is usually temporary, and infection, urinary stones, foreign-body reactions, and discomfort may occur. The stent replacement interval varies according to the patient’s condition and the material, and evaluation is generally needed every few months.
  • Percutaneous nephrostomy: Secures direct urine drainage from the kidney in emergencies such as urinary obstruction or sepsis.
  • Endoscopic balloon dilation (or endoscopic incision/endoscopic ureterotomy with laser or knife incision): Enlarges or incises the stricture to secure a passage. It is minimally invasive, but the recurrence rate may be high. Stent insertion is performed concurrently after the procedure.
• Surgical treatment
  • Ureteral resection and anastomosis (for short strictures), ureteral reimplantation (for distal strictures), psoas hitch and Boari flap (to compensate for defects in the middle to distal ureter), and ureteral replacement using bowel (such as the ileum; for long defects), among others. These procedures are performed through open, laparoscopic, or robotic surgery.
  • If the cause is malignant, tumor treatment is performed concurrently.
• Medication and supportive treatment
  • If there is an accompanying infection, appropriate antibiotic therapy (based on culture results).
  • Pain control and encouraging fluid intake.
• Lifestyle management and follow-up
  • If a stent has been inserted, regular replacement and monitoring for signs of infection are necessary. Seek medical attention immediately if symptoms of a urinary tract infection (fever, severe pain, frequent urination, or painful urination) occur.
  • Kidney function and recurrence of obstruction are monitored through regular imaging (ultrasound, CT, or nuclear medicine testing) and blood tests (creatinine).
• Precautions (points of caution, risk of complications, and self-care)
  • Stent-related discomfort (urinary frequency/urgency, painful urination, and hematuria), infection, and the possibility of stent encrustation, calcification, or migration.
  • Delayed treatment may result in permanent kidney damage due to persistent hydronephrosis.
  • Inform the doctor about the use of anticoagulants and the possibility of pregnancy before the procedure.
  • Emergency medical care is necessary if fever, severe flank pain, or difficulty urinating occurs.

Checklist Before an Outpatient Visit (Including Items to Bring and Sample Questions)

• Items and test records to bring
  • A list of all medications currently being taken (including anticoagulants and antiplatelet drugs).
  • A history of previous surgeries (including abdominal and urinary tract surgeries) and trauma.
  • Recent imaging (CT and ultrasound), blood test results (including creatinine), and urinalysis and culture results, if available (as printed copies or electronic files).
  • A record of when symptoms began and how they have changed (onset and frequency of pain, whether fever occurred, hematuria, and so on).
• Questions to prepare for the outpatient visit (examples of items the patient may note in advance)
  • Have you recently had a fever or systemic symptoms (such as chills or nausea)?
  • Have you ever been treated for a urinary tract infection, or have you recently taken antibiotics?
  • Have you recently had urinary stones or undergone a related procedure?

Examples of General Questions to Ask the Doctor

• What appears to be the cause of this stricture?
• How much of my kidney function has been preserved (for example, what are the results of the nuclear medicine test)?
• Which option do you recommend for me—nonsurgical or surgical treatment—and why?
• What discomfort and side effects can be expected with stent insertion, and how often should it be replaced?
• What is the schedule for follow-up tests (imaging and blood tests) after treatment?
• What self-care measures can I take to reduce complications (restenosis, infection, and decreased kidney function)?

Examples of Disease-Specific Questions

• Could you explain specifically the location (proximal, middle, or distal) and length of the stricture (for example, how many cm) and its cause?
• What is my current relative kidney function (split renal function percentage), and what treatment is recommended to preserve this function?