Is a stent needed for ureteral obstruction?

Stent Use in Ureteral Obstruction

Stents are not routinely needed for ureteral obstruction but are clearly indicated in specific clinical scenarios including ureteral injury, stricture, solitary kidney, renal insufficiency, or large residual stone burden. 1

Indications for Stent Placement

Stents should be placed in the following situations:

• Ureteral injury during ureteroscopy to prevent further complications 1
• Pre-existing ureteral stricture to maintain patency 1
• Solitary kidney to prevent complete obstruction 1
• Renal insufficiency to maintain drainage and prevent further kidney damage 1
• Large residual stone burden after ureteroscopy to ensure proper drainage 1
• Ureteric obstruction with infection/sepsis prior to definitive ureteroscopic stone extraction 1
• Patients with fever, leukocytosis, and obstructing stone to alleviate symptoms and prevent complications 1

When Stents Are Not Needed

• Routine stenting is not recommended as part of shock wave lithotripsy (SWL) 2
• Stenting following uncomplicated ureteroscopy (URS) is optional, not mandatory 2
• Following uncomplicated ureteroscopy or SWL, routine stenting does not appear to affect the stone-free rate 3

Complications of Stent Placement

Stent placement is associated with several complications that should be considered:

• Lower urinary tract symptoms and pain that can temporarily affect quality of life 2, 1
• Stent migration (approximately 5% of cases) 1
• Urinary tract infection (2-6% risk) 1
• Other complications include stent breakage, encrustation, and obstruction 2
• Secondary cystoscopy is required for stent removal unless a pull string is attached 2, 1

Management of Stent Occlusions

If stent occlusion occurs:

• When stent replacement fails due to complete occlusion, percutaneous nephrostomy should be placed 4
• Antegrade access with conversion to a percutaneous nephroureteral stent may be required for complicated cases 4
• If enlarging urinoma, fever, increasing pain, ileus, fistula or infection are present, urinary drainage should be performed via ureteral stent 4

Special Considerations

• In patients with urinary diversion, image-guided percutaneous antegrade access is often preferred 4, 5
• Internal double-J stents tend to occlude quickly in ileal conduits due to mucous plugging 4, 5
• For malignant ureteral obstruction, percutaneous nephrostomy tubes may be preferred over stents due to higher success rates, though they can reduce quality of life 6, 7
• Alternative options for malignant obstruction include tandem stents, metallic stents, and extra-anatomic stents 8

Decision Algorithm for Stent Placement

1. Assess for specific indications requiring stent placement (injury, stricture, solitary kidney, renal insufficiency, large stone burden)
2. If any indication is present, proceed with stent placement 1
3. If no specific indication is present and procedure was uncomplicated, stent placement is optional 2
4. Consider patient factors that may increase risk of complications (bilateral procedures, recent/recurrent UTIs, pregnancy) 3
5. For malignant obstruction, evaluate alternative drainage options based on expected survival and quality of life considerations 7, 8