Urgent Urological Consultation for Obstructed Infected Stone
The next step is immediate consultation with urology for urgent drainage of the obstructed collecting system via either retrograde ureteral stent placement or percutaneous nephrostomy, followed by definitive stone removal once the infection is controlled. This patient has obstructive pyelonephritis with a large stone causing hydronephrosis, which represents a urological emergency requiring prompt decompression.
Rationale for Urgent Drainage
When purulent urine or infected hydronephrosis is encountered during stone disease with obstruction, clinicians must abort elective stone removal, establish appropriate drainage, continue antibiotic therapy, and obtain urine cultures 1. The combination of obstruction, infection, and fever creates risk for rapid progression to urosepsis and septic shock.
Appropriate management of the urological abnormality or underlying complicating factor is mandatory in complicated UTI 1. The 15 mm stone causing hydronephrosis represents both the source of infection and the obstructing factor that must be addressed urgently.
The obstructed, infected kidney is a urological emergency requiring prompt decompression of the collecting system 2, 3. Ureteric obstruction predisposes to pyelonephritis and causes renal dysfunction that impairs antibiotic excretion, making bacterial eradication difficult 3.
Drainage Options
Both retrograde ureteral stent and percutaneous nephrostomy are acceptable options:
Randomized trials comparing retrograde stent insertion with percutaneous nephrostomy in acute sepsis and obstruction showed neither modality was superior in effecting decompression and resolution of sepsis 2. The choice depends on local expertise and patient factors.
There is little evidence suggesting retrograde stent insertion leads to increased bacteremia or is significantly more hazardous in acute obstruction 2.
Why Outpatient Management is Inappropriate
The suggested approach of 14 days of antibiotics with outpatient urology follow-up and repeat imaging in two days is dangerously inadequate for several reasons:
This patient has systemic signs of infection (fever, leukocytosis) combined with obstruction—a combination that can rapidly progress to urosepsis 1. Waiting two days for repeat imaging risks clinical deterioration.
Antibiotic therapy alone without relieving obstruction is insufficient 3. The obstructed system prevents adequate antibiotic penetration and bacterial clearance.
Treatment duration should be closely related to treatment of the underlying abnormality 1. The 15 mm stone will not pass spontaneously and requires intervention.
Definitive Stone Management
After infection control with drainage and antibiotics:
The stone procedure should be undertaken once the infection is appropriately treated 1. This typically requires 24-48 hours of clinical improvement with drainage and antibiotics.
For a 15 mm stone in the pelvicalyceal junction, endoscopic management via ureteroscopy (URS) or percutaneous nephrolithotomy (PCNL) will be required 1. Stones this large rarely pass spontaneously.
If infection stones are suspected, removal is crucial to limit further stone growth, recurrent UTIs, and renal damage 4.
Antibiotic Management
Continue IV antibiotics empirically with a combination such as amoxicillin plus aminoglycoside, second-generation cephalosporin plus aminoglycoside, or IV third-generation cephalosporin 1.
Treatment duration of 7-14 days is generally recommended for complicated UTI 1, but this should be tailored based on clinical response and culture results.
Initial empiric therapy should be tailored once culture results return 1.
Common Pitfalls to Avoid
Never attempt definitive stone removal in the setting of active infection with purulent urine 1. This dramatically increases sepsis risk.
Do not delay drainage while waiting for culture results 2, 3. Drainage is the priority, with cultures obtained at the time of drainage.
Avoid outpatient management of obstructed pyelonephritis—these patients require hospitalization for IV antibiotics and urgent drainage 1.