What is the recommended treatment for ureteropelvic junction (UPJ) obstruction?

Treatment of Ureteropelvic Junction Obstruction

Minimally invasive surgical approaches should be the first-line treatment for ureteropelvic junction (UPJ) obstruction, with laparoscopic pyeloplasty being the gold standard for most cases due to its high success rate and favorable morbidity profile.

Diagnostic Evaluation

Before determining treatment, proper diagnosis is essential:

• CT scan with contrast and delayed images for accurate assessment of anatomy and degree of obstruction 1
• Diuretic renogram to evaluate renal function and degree of obstruction
• Retrograde pyelography to rule out concurrent ureterovesical junction obstruction 2

Treatment Algorithm

1. Initial Assessment Factors

• Severity of obstruction
• Presence of symptoms (flank pain, recurrent infections)
• Renal function
• Anatomical considerations (crossing vessels, long stricture)
• Patient factors (age, comorbidities)

2. Treatment Options Based on Obstruction Type

For Intrinsic UPJ Obstruction:

• Percutaneous endopyelotomy is recommended as first-line treatment 3
  • Success rate of 92.8%
  • Shorter operative time (mean 1.2 hours)
  • Faster recovery

For Extrinsic or Complex UPJ Obstruction:

• Laparoscopic dismembered pyeloplasty (Anderson-Hynes technique) is preferred 1, 3
  • Indicated for:
    • Crossing vessels (found in ~50% of cases)
    • Extremely distended renal pelvis
    • Long strictures (>2 cm)
    • Failed previous repairs
  • Success rate approaching 100%
  • Longer operative time (mean 3.5 hours) but excellent outcomes

For Equivocal UPJ Obstruction:

• In symptomatic patients with equivocal findings on diuretic renogram but with clinical symptoms and hydronephrosis, minimally invasive pyeloplasty still provides excellent outcomes (95.7% symptom resolution) 4

3. Special Considerations

• Failed primary repair: Repeat pyeloplasty or ureterocalicostomy may be necessary 5

  • Dense scar tissue and redundant pelvis are common findings
  • Nephrostomy tube and transanastomotic stent placement advisable

• Concomitant reconstruction: In cases requiring reconstruction (e.g., ureteral stricture), open/laparoscopic/robotic approaches may be considered 1

Important Technical Considerations

• Safety guidewire should be used during endoscopic procedures 1
• Antimicrobial prophylaxis should be administered prior to intervention 1
• If purulent urine is encountered, abort procedure, establish drainage, and continue antibiotics 1
• Stone material, if present, should be sent for analysis 1

Pitfalls to Avoid

1. Missing concurrent ureterovesical junction obstruction: Always consider retrograde pyelography to identify distal obstructions that could lead to pyeloplasty failure 2

2. Inadequate preoperative imaging: Failure to identify crossing vessels or other anatomical variants can lead to suboptimal surgical approach selection

3. Improper patient selection: Not all patients with hydronephrosis require intervention; asymptomatic patients with preserved renal function may be observed

4. Inappropriate surgical approach: Open surgery should not be first-line for most patients with UPJ obstruction unless there are specific anatomical abnormalities requiring reconstruction 1

Follow-up

• Diuretic renogram at 3-6 months post-procedure
• Ultrasound to assess for resolution of hydronephrosis
• Monitoring for symptom resolution
• Long-term follow-up for recurrent obstruction, especially in complex cases

By following this structured approach to UPJ obstruction management, optimal outcomes with preservation of renal function and symptom resolution can be achieved in the vast majority of patients.