What is the treatment for renal hydronephrosis?

Treatment of Renal Hydronephrosis

Prompt decompression of the collecting system via percutaneous nephrostomy (PCN) or retrograde ureteral stenting is the recommended first-line treatment for hydronephrosis to prevent permanent renal damage. 1

Diagnostic Evaluation

Before initiating treatment, identifying the underlying cause of hydronephrosis is crucial:

• Initial imaging: CT urography is preferred for adults with severe hydronephrosis
• Functional assessment: Diuretic renography (MAG3 scan) to evaluate drainage and differential renal function
• Common causes: Urolithiasis, malignant obstruction, ureteropelvic junction obstruction (PUJO), strictures, retroperitoneal fibrosis, extrinsic compression, and bladder outlet obstruction

Treatment Algorithm

1. Emergency Decompression (for infected hydronephrosis or acute obstruction)

• First-line options:

  • Percutaneous nephrostomy (PCN): Higher technical success rate (>95% for dilated systems) and provides direct access for bacteriological sampling 1
  • Retrograde ureteral stenting: Better tolerated by patients but may have higher risk of urosepsis in extrinsic ureteral obstruction 1

• Antibiotic therapy: Initiate promptly with third-generation cephalosporins (such as ceftazidime) which show superiority over fluoroquinolones 1

2. Definitive Treatment Based on Etiology

• Urolithiasis: Stone removal after initial decompression
• PUJO (accounts for 91.4% of giant hydronephrosis cases): Reduction pyeloplasty with nephropexy for functioning kidneys 2
• Malignant obstruction: Long-term decompression with ureteral stent or PCN and treatment of underlying malignancy 1
• Pregnancy-related hydronephrosis:
  • Asymptomatic cases (70-90%): No intervention required
  • Symptomatic cases (0.2-4.7%): Retrograde ureteral stenting with minimal or no fluoroscopy 1

3. Nephrectomy Considerations

• Indicated for non-functioning kidneys (differential function <10-15%)
• In giant hydronephrosis, nephrectomy rate is approximately 37.1% due to non-functioning kidneys 2

Special Considerations

Pediatric Patients

• Initial ultrasound 48-72 hours after birth for antenatal hydronephrosis
• Follow-up based on severity
• VCUG for moderate to severe cases to rule out vesicoureteral reflux
• Antibiotic prophylaxis may be considered for moderate to severe cases 1

Pregnant Patients

• Minimize radiation exposure during interventions
• Retrograde ureteral stenting with minimal or no fluoroscopy for symptomatic cases with infection
• PCN as alternative when retrograde stenting is not technically feasible 1

Complications and Follow-up

• Potential complications if untreated: Acute kidney injury, urinary tract infection/urosepsis, permanent nephron loss, hypertension, and growth retardation (in pediatric cases) 1
• Monitoring: Regular assessment of renal function with serial creatinine measurements
• Imaging: Follow-up ultrasound to confirm resolution of hydronephrosis
• Long-term management: Treatment of underlying cause, regular monitoring of renal function, and periodic replacement of stents or nephrostomy tubes as needed 1

Pitfalls to Avoid

• Delayed diagnosis: Can lead to life-threatening sepsis and permanent renal damage
• Inadequate decompression: Ensure complete drainage of the collecting system
• Neglecting the underlying cause: Treating only the hydronephrosis without addressing the primary etiology will lead to recurrence
• Overlooking associated conditions: Giant hydronephrosis may mask other anatomical abnormalities such as horseshoe kidney 3