Treatment of Candida tropicalis UTI
For symptomatic Candida tropicalis cystitis, treat with oral fluconazole 200 mg (3 mg/kg) daily for 2 weeks, which is the first-line therapy recommended by IDSA guidelines. 1, 2
Initial Assessment and Decision to Treat
Asymptomatic candiduria does NOT require treatment unless the patient falls into high-risk categories: neutropenic patients, very low-birth-weight infants, or those undergoing urologic procedures. 1, 2
- Remove or replace urinary catheters immediately if present, as this alone resolves candiduria in approximately 50% of cases and represents the critical first step in management. 2, 3
- Elimination of predisposing factors (catheters, antibiotics, obstruction) often results in spontaneous resolution without antifungal therapy. 1
Treatment Algorithm by Clinical Presentation
Symptomatic Cystitis (Lower UTI)
- Primary therapy: Fluconazole 200 mg (3 mg/kg) orally daily for 2 weeks 1, 2
- This regimen demonstrates 82% efficacy and achieves high urinary concentrations. 2, 3
- Continue treatment until symptoms resolve AND urine cultures no longer yield Candida species. 2
Pyelonephritis (Upper UTI)
- Primary therapy: Fluconazole 200-400 mg (3-6 mg/kg) orally daily for 2 weeks 1, 2
- Use the higher dose range (400 mg) for more severe upper tract infections. 2
Alternative Regimens (if fluconazole cannot be used)
- Amphotericin B deoxycholate 0.3-0.6 mg/kg IV daily for 1-7 days 1, 3
- Flucytosine 25 mg/kg orally 4 times daily for 7-10 days 1, 3
- These alternatives are reserved for fluconazole resistance, allergy, or treatment failure. 4
Special Population Considerations
Patients Undergoing Urologic Procedures
- Prophylactic treatment: Fluconazole 200-400 mg (3-6 mg/kg) daily OR amphotericin B deoxycholate 0.3-0.6 mg/kg daily for several days before and after the procedure 1, 3
Neutropenic Patients and Neonates
- Manage as invasive candidiasis rather than isolated UTI. 1
- For neonates: Amphotericin B deoxycholate 1 mg/kg daily OR fluconazole 12 mg/kg IV/oral daily (if not on fluconazole prophylaxis). 2
Suspected Disseminated Candidiasis
- Treat as candidemia with systemic antifungal therapy, not as isolated UTI. 1
Critical Management Considerations
Eliminate urinary tract obstruction as this is essential for treatment success. 5
- For patients with nephrostomy tubes or stents, consider removal or replacement if feasible. 5, 3
- Obtain imaging if treatment fails despite appropriate therapy to rule out fungus balls, hydronephrosis, or abscesses. 2
Fungus Balls
- Require surgical intervention in addition to antifungal therapy 1, 2
- Systemic fluconazole 200-400 mg (3-6 mg/kg) daily PLUS surgical removal 1
- If access to renal collecting system available, adjunctive irrigation with amphotericin B 50 mg/L sterile water 1
Common Pitfalls to Avoid
Do NOT use echinocandins (caspofungin, micafungin, anidulafungin) for lower urinary tract infections, as they achieve minimal urinary excretion and are generally ineffective for Candida UTI. 5, 6, 7
Do NOT use lipid formulations of amphotericin B (liposomal, lipid complex), as they do not achieve adequate urine concentrations. 5
Do NOT use other azoles besides fluconazole (voriconazole, posaconazole, itraconazole) for UTI treatment, as they fail to achieve sufficient urinary levels. 7
Amphotericin B bladder irrigation is generally NOT recommended due to high recurrence rates (80-90% initial resolution but poor durability), though it may be considered for fluconazole-resistant species like C. glabrata. 1, 3
Monitoring and Follow-up
- Monitor for clinical improvement and obtain follow-up urine cultures to confirm clearance of infection. 5
- Colony counts cannot reliably differentiate colonization from infection, especially with catheters in place. 3
- For persistent infection despite appropriate therapy, obtain imaging to evaluate for anatomical abnormalities or complications. 2