What are the management options for urinary obstruction?

Management of Urinary Obstruction

Urinary obstruction can lead to infection, stone formation, and increased pressure in the renal pelvis, requiring prompt identification and management to prevent kidney damage and potential life-threatening complications.

Diagnostic Approach

• CT scan is recommended to identify hydronephrosis, perinephric stranding, and potential causes of obstruction, especially with clinical presentation of flank pain, fever, and leukocytosis indicating possible infection with obstruction 1
• Assessment should include signs of sepsis, renal function, electrolyte abnormalities, and urinalysis to check for blood and infection 1

Indications for Urgent Decompression

• Pyonephrosis/obstructive pyelonephritis with sepsis 1
• Acute kidney injury with significant renal dysfunction 1
• Bilateral obstruction or obstruction of a solitary functioning kidney 1

Decompression Methods

Percutaneous Nephrostomy (PCN)

• First-line approach for septic patients, with a 92% survival rate compared to 60% with medical therapy alone 1
• Technical success rates approach 100% when accessing dilated collecting systems and 80-90% for non-dilated systems 2
• Preferred for extrinsic compression of the ureter, obstruction involving the ureterovesical junction, and cases where retrograde access is challenging 1
• Complication rates are generally low (approximately 10%) 2
• Common complications include catheter displacement, bleeding, and sepsis 2

Retrograde Ureteral Stenting (RUS)

• First-line therapy for management of ureteral obstruction caused by gynecologic malignancies 1
• Preferred when a patient requires general anesthesia for other procedures 1
• In cases of acute ureteral obstruction, retrograde double-J ureteral stenting has been shown to be successful for complete stone eradication 2

Antibiotic Management

• Preprocedural antibiotics are recommended when urosepsis is suspected 2
• Third-generation cephalosporins show superiority over fluoroquinolones in clinical and microbiological cure rates 2
• Recent study demonstrates superiority of third-generation cephalosporin ceftazidime versus fluoroquinolone ciprofloxacin in both clinical and microbiological cure rates 2

Special Considerations

Post-Urinary Diversion Obstruction

• Image-guided percutaneous antegrade access is generally preferred due to difficulty visualizing the ureteric opening in the bowel conduit 2
• Retrograde PCNU catheters are generally preferred over retrograde "internal" double-J ureteral stents because the latter tend to occlude quickly due to mucous plugging within the ileal conduit 2

Stone-Related Obstruction

• Medical management is primarily indicated for preprocedural antibiotic treatment and postprocedural care 2
• Without evidence of obstruction, medical management with fluids and intravenous antibiotics, and close clinical and imaging follow-up could be considered 2

Malignant Obstruction

• PCN can improve renal function and survival, particularly in prostate and transitional cell carcinomas 1
• For palliative cases, consider the quality of life impact as PCN may offer little benefit when survival is limited 1

Follow-up Management

• For temporary decompression, consider definitive treatment of the underlying cause 1
• Surgical revision or re-anastomosis should be considered for definitive therapy of ureteral-ileal conduit strictures 1
• Monitor for nephrocalcinosis and kidney stones with renal ultrasound every 12-24 months 1

Complications and Pitfalls

• Risk of developing pyelonephritis or asymptomatic bacteriuria after PCN placement, with neutropenia and history of urinary tract infection being significant risk factors 1
• Postprocedural bacteremia and sepsis are common when draining infected urinary tracts 1
• PCN tubes may cause patient discomfort, skin irritation, or infection at the catheter exit site 1
• Mild hematuria is present in approximately 50% of patients after PCN 2
• Clinically significant bleeding, either into the collecting system or into the retroperitoneum, is less common 2
• Less common complications related to PCN include bowel injury, splenic injury, gallbladder puncture, and pneumothorax 2

Long-term Management

• Without evidence of declining renal function or infection, conservative management could be considered until clinical status changes 1
• Obstructive uropathy is one of the leading causes of acute kidney injury, accounting for 5%-10% of cases 3, 4
• Early recognition and treatment is paramount to prevent progressive renal deterioration 5