Treatment of Fungal Urinary Tract Infections in Female Patients
Fluconazole is the first-line treatment for symptomatic fungal urinary tract infections in female patients, with a recommended dose of 200-400 mg daily for 2 weeks. 1
Diagnostic Considerations
Before initiating treatment, it's important to distinguish between fungal colonization and true infection:
- Fungal concentration >10³/mm³ in urine suggests significant funguria 2
- Presence of symptoms (dysuria, frequency, urgency) indicates need for treatment
- Obtain urine culture to identify the specific fungal species and guide therapy
Treatment Algorithm
1. Asymptomatic Candiduria
- No treatment required in most cases 1
- Remove predisposing factors (indwelling catheters, antibiotics) which will clear candiduria in almost 50% of cases 3
- Treatment indicated only for high-risk patients:
- Neutropenic patients
- Patients undergoing urologic procedures
- Pregnant women
2. Symptomatic Cystitis
- First-line treatment: Fluconazole 200-400 mg daily for 2 weeks 1
- Alternative for fluconazole-resistant species (e.g., C. glabrata, C. krusei):
3. Pyelonephritis
- Fluconazole 200-400 mg daily for 2 weeks 1
- Alternative therapy for resistant organisms:
- Amphotericin B deoxycholate 0.5-0.7 mg/kg daily with or without flucytosine 1
4. Fungal Balls (Mycetoma)
- Surgical removal strongly recommended 1
- Antifungal therapy should be administered concurrently
- Local irrigation with amphotericin B may be used as an adjunct to systemic therapy 1
Special Considerations
Resistant Organisms
- C. glabrata and C. krusei often show resistance to fluconazole
- For these species, consider:
- Amphotericin B bladder irrigation
- Flucytosine (if susceptible)
- Removal of any obstructing lesions 1
Catheters and Stents
- Remove or exchange indwelling catheters whenever possible 2
- For patients with permanent drainage tubes or stents and symptomatic fungal UTIs:
- Ensure fungicidal levels are present before exchanging tubes/stents 1
Monitoring
- Follow-up urine cultures to confirm eradication
- Monitor renal function when using amphotericin B due to nephrotoxicity risk 4
Prevention Strategies
- Limit antibiotic use to reduce risk of fungal overgrowth 2
- Optimize diabetes management in diabetic patients 2
- Prompt removal of urinary catheters when no longer needed 2, 3
Important Caveats
- Newer azoles and echinocandins are not recommended for urinary tract infections as they fail to achieve adequate urine concentrations 3
- The ability of the antifungal agent to achieve adequate concentrations in urine is as important as the antifungal susceptibilities of the infecting species 1
- Fluconazole is particularly effective because it is excreted into the urine in its active form and easily achieves urine levels exceeding the MIC for most Candida isolates 1