What is the best course of action for a 73-year-old female with a history of multi-drug resistant (MDR) urinary tract infections (UTIs), currently with a nephrostomy tube in her single kidney, being treated with Cefepime (Cefepime) 1g intravenous (IV) every 24 hours, and having a positive nitrate test on urinalysis (UA) but no leucocytosis or fever?

Management of Recurrent MDR UTI in a 73-Year-Old Female with Nephrostomy Tube

For this 73-year-old female with a history of multidrug-resistant UTIs, a single kidney with nephrostomy tube, and positive nitrates on urinalysis, infectious disease consultation is strongly recommended while continuing Cefepime 1g IV every 24 hours pending culture results. 1

Current Assessment

• 73-year-old female with recurrent MDR UTI
• Left side nephrostomy tube, single kidney
• Last UTI treated 10/13/2025 with Cefepime 1g IV q24h
• Current presentation: Nitrate positive UA, no leukocytosis, afebrile, stable vitals
• Urine culture pending

Immediate Management

• Continue current Cefepime 1g IV q24h regimen while awaiting culture and susceptibility results 2, 3
• Obtain infectious disease consultation as this is highly recommended for management of MDR organism infections 1
• Ensure appropriate dose adjustment for renal function (current dose appears appropriate for CrCl 30-60 mL/min) 2

Once Culture Results Available

If Carbapenem-Resistant Enterobacterales (CRE) is identified:

• First-line options:

  • Ceftazidime-avibactam 2.5g IV q8h (adjust for renal function) 1
  • Meropenem-vaborbactam 4g IV q8h (adjust for renal function) 1, 4
  • Imipenem-cilastatin-relebactam 1.25g IV q6h (adjust for renal function) 1, 4

• Alternative options:

  • Plazomicin 15 mg/kg IV q12h (adjust for renal function) 1, 5
  • Single-dose aminoglycoside may be considered for uncomplicated cystitis due to CRE 1

If ESBL-producing organism is identified:

• Continue carbapenem therapy or consider targeted therapy based on susceptibility 1, 5
• Prolonged infusion of β-lactams for pathogens with high MIC is recommended 1

If susceptible to current therapy:

• Complete 7-14 days of therapy with Cefepime 1g IV q24h 1, 3
• Consider oral step-down therapy once clinically improved if susceptible options are available 1, 6

Special Considerations

• Nephrostomy tube management:

  • Consider nephrostomy tube exchange if recurrent infections persist despite appropriate antibiotic therapy 6
  • Ensure proper care of nephrostomy tube site 6

• Dosing considerations:

  • Cefepime dose should be adjusted based on creatinine clearance (current 1g q24h is appropriate for CrCl 30-60 mL/min) 2
  • For severe infections with susceptible organisms, consider increasing to Cefepime 2g q24h if renal function permits 2

Follow-up Recommendations

• Obtain follow-up urine cultures after completion of therapy to confirm eradication 6
• Consider prophylactic strategies if recurrent infections continue 6, 5
• Monitor renal function throughout treatment course 2

Common Pitfalls to Avoid

• Avoid empiric use of fluoroquinolones due to high resistance rates in patients with history of MDR UTIs 6, 5
• Do not delay obtaining cultures before initiating or changing antibiotic therapy 1
• Do not use tigecycline monotherapy for UTIs as it has poor urinary concentration 1
• Do not continue broad-spectrum therapy without de-escalation once susceptibility results are available 1, 6