What is the treatment for urinary candida (fungal infection) that is not Candida albicans?

Treatment for Urinary Tract Infections Caused by Non-albicans Candida Species

For urinary tract infections caused by non-albicans Candida species, oral fluconazole at a dosage of 200-400 mg (3-6 mg/kg) daily for 2 weeks is the first-line treatment for susceptible strains, while amphotericin B deoxycholate or flucytosine are recommended for fluconazole-resistant species. 1

Treatment Algorithm Based on Infection Site and Susceptibility

1. Cystitis (Lower UTI)

• For fluconazole-susceptible non-albicans species:

  • Oral fluconazole 200 mg (3 mg/kg) daily for 2 weeks 1
  • Remove predisposing factors (indwelling catheters, antibiotics) 2

• For fluconazole-resistant species (e.g., C. glabrata, C. krusei):

  • Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days 1
  • OR oral flucytosine 25 mg/kg 4 times daily for 7-10 days 1
  • In difficult cases: Amphotericin B bladder irrigation may be useful 1

2. Pyelonephritis (Upper UTI)

• For fluconazole-susceptible non-albicans species:

  • Oral fluconazole 200-400 mg (3-6 mg/kg) daily for 2 weeks 1

• For fluconazole-resistant species:

  • Amphotericin B deoxycholate 0.5-0.7 mg/kg daily with or without flucytosine 25 mg/kg 4 times daily for 2 weeks 1
  • OR flucytosine alone 25 mg/kg 4 times daily for 2 weeks 1

3. Fungus Balls

• Surgical intervention is strongly recommended 1
• Systemic antifungal therapy as above based on susceptibility
• If access to collecting system is available: irrigation with amphotericin B (50 mg/L sterile water) 1, 3
• Continue treatment until symptoms resolve and urine cultures are negative for Candida 1

Important Considerations

Pharmacokinetics

• Fluconazole: Achieves high urine concentrations, making it ideal for urinary infections 1, 2
• Flucytosine: Good urinary concentration but risk of toxicity and resistance development when used alone 1
• Amphotericin B deoxycholate: Achieves adequate urine concentrations 1
• Echinocandins and newer azoles: Not recommended due to poor urinary excretion 1, 2
• Lipid formulations of amphotericin B: Not recommended due to inadequate urine concentrations 1

Species-Specific Considerations

• C. parapsilosis: Generally responsive to fluconazole (93% efficacy) 4
• C. tropicalis: Generally responsive to fluconazole (82% efficacy) 4
• C. glabrata: Lower response to fluconazole (50% efficacy); may require higher doses or alternative agents 4
• C. krusei: Intrinsically resistant to fluconazole; should not be treated with fluconazole 4

Common Pitfalls to Avoid

1. Treating asymptomatic candiduria: Most cases represent colonization rather than infection 3
2. Relying on colony counts: Unlike bacterial UTIs, colony counts cannot reliably differentiate infection from colonization 1
3. Using echinocandins for urinary infections: Despite some case reports of success, these agents generally fail due to poor urinary concentrations 1
4. Using lipid formulations of amphotericin B: These do not achieve adequate urine concentrations 1
5. Overlooking fungus balls: These require surgical intervention in addition to antifungal therapy 1
6. Failing to remove predisposing factors: Removing catheters and discontinuing antibiotics can clear candiduria in almost 50% of cases 2

Diagnostic Approach

• Confirm infection versus colonization through clinical presentation and imaging
• Ultrasound or CT scanning to identify structural abnormalities, hydronephrosis, abscesses, or fungus balls 1
• Consider species identification and susceptibility testing, particularly for treatment failures 1

Recent research suggests that combination therapy may be promising for resistant strains, with fluconazole/colistin showing potential in reducing bladder bioburden and inflammatory response in experimental models 5, though this approach requires further clinical validation before routine use.