What is the recommended treatment for Candida albicans urinary tract infections (UTI)?

Treatment of Candida albicans Urinary Tract Infections

Fluconazole is the recommended first-line treatment for symptomatic Candida albicans urinary tract infections, with a loading dose of 200 mg followed by 200 mg daily for 2 weeks for cystitis and 200-400 mg daily for 2 weeks for pyelonephritis. 1

Treatment Algorithm for Candida albicans UTI

Step 1: Determine if Treatment is Necessary

• Asymptomatic candiduria: Generally does not require treatment unless patient belongs to high-risk groups:
  • Immunocompromised patients
  • Patients undergoing urologic procedures
  • Patients with suspected disseminated fungal infections 1
• Symptomatic candiduria: Requires antifungal therapy 1

Step 2: Remove Predisposing Factors

• Remove or replace indwelling catheters if present (resolves ~50% of cases) 1
• Address underlying conditions (diabetes, antibiotics use, etc.)

Step 3: Select Appropriate Treatment Based on Susceptibility

For Fluconazole-Susceptible C. albicans:

• Cystitis: Fluconazole 200 mg loading dose, then 200 mg daily for 2 weeks 1
• Pyelonephritis: Fluconazole 200 mg loading dose, then 200-400 mg daily for 2 weeks 1
• For patients on hemodialysis: 200 mg loading dose followed by 200 mg after each dialysis for cystitis, 200-400 mg after each dialysis for pyelonephritis 1

For Fluconazole-Resistant C. albicans:

1. First option: Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days 1
2. Second option: Oral flucytosine 25 mg/kg 4 times daily for 7-10 days (should not be used as monotherapy due to risk of resistance) 1

Special Considerations

Complicated Infections

• For fungus balls or abscesses: Surgical debridement plus systemic antifungal therapy 1
• Local irrigation with amphotericin B at 50 mg/L of sterile water may be considered as adjunct therapy 1

Medication Selection Rationale

• Fluconazole is preferred due to:
  • Excellent urinary concentrations
  • Effectiveness against most Candida species
  • Availability in both oral and IV formulations 1, 2
• Echinocandins (caspofungin, micafungin) achieve poor urinary concentrations and should not be used for uncomplicated Candida UTIs 1, 3
• Lipid formulations of amphotericin B should not be used for lower UTIs due to inadequate urine concentrations 1

Monitoring

• Follow-up urine cultures to confirm eradication
• Monitor renal function when using amphotericin B
• For flucytosine, drug level monitoring is recommended 1

Common Pitfalls to Avoid

1. Treating asymptomatic candiduria in non-high-risk patients 1
2. Failing to remove indwelling catheters 1
3. Using antifungals with poor urinary concentrations (echinocandins, newer azoles) for uncomplicated UTIs 1
4. Using flucytosine as monotherapy 1
5. Inadequate treatment duration (should be 2 weeks or until symptoms resolve and cultures are negative) 1

The evidence strongly supports fluconazole as the first-line treatment for Candida albicans UTIs due to its efficacy, safety profile, and high urinary concentrations 1, 4, 5. For fluconazole-resistant strains, amphotericin B deoxycholate or flucytosine are appropriate alternatives 1.