What is the recommended treatment for a patient with a Candida urinary tract infection (UTI)?

Treatment of Candida Urinary Tract Infection

For symptomatic Candida UTI, oral fluconazole 200 mg daily for 2 weeks is the first-line treatment for fluconazole-susceptible organisms, combined with immediate removal of any indwelling urinary catheter. 1

Initial Management Steps

Remove the urinary catheter immediately if present – this single intervention resolves candiduria in approximately 50% of cases and is strongly recommended before or concurrent with antifungal therapy. 1, 2, 3

Determine if treatment is actually indicated:

• Asymptomatic candiduria does NOT require treatment in most patients 1
• Treat only if: neutropenic, very low-birth-weight infant (<1500g), or undergoing urologic procedures within days 1, 4
• Symptomatic patients (dysuria, urgency, frequency, flank pain, fever) require treatment 1

Treatment Algorithm by Clinical Presentation

For Cystitis (Lower UTI)

Fluconazole-susceptible species (most C. albicans, C. tropicalis, C. lusitaniae):

• Fluconazole 200 mg (3 mg/kg) orally daily for 2 weeks 1, 2, 5
• This achieves high urinary concentrations and has moderate-quality evidence supporting efficacy 1
• Recent data suggest 7 days may be sufficient (93.1% vs 93.3% success for <14 vs 14 days), though guidelines still recommend 14 days 6

Fluconazole-resistant C. glabrata:

• Amphotericin B deoxycholate 0.3-0.6 mg/kg IV daily for 1-7 days OR flucytosine 25 mg/kg orally 4 times daily for 7-10 days 1, 3
• Amphotericin B bladder irrigation (50 mg/L sterile water daily for 5 days) may be added for resistant cystitis 1

C. krusei (inherently fluconazole-resistant):

• Amphotericin B deoxycholate 0.3-0.6 mg/kg IV daily for 1-7 days 1

For Pyelonephritis (Upper UTI)

Fluconazole-susceptible species:

• Fluconazole 200-400 mg (3-6 mg/kg) orally daily for 2 weeks 1
• Use the higher 400 mg dose for more severe upper tract infections 2

Fluconazole-resistant C. glabrata:

• Amphotericin B deoxycholate 0.3-0.6 mg/kg IV daily for 1-7 days with or without flucytosine 25 mg/kg orally 4 times daily 1, 3
• Monotherapy with flucytosine 25 mg/kg orally 4 times daily for 2 weeks is a weaker alternative 1

Eliminate urinary tract obstruction – this is strongly recommended and essential for treatment success 1

For Patients Undergoing Urologic Procedures

Prophylactic treatment is required:

• Fluconazole 400 mg (6 mg/kg) daily OR amphotericin B deoxycholate 0.3-0.6 mg/kg daily for several days before and after the procedure 1

Critical Management Principles

Species identification and susceptibility testing are essential – C. glabrata exhibits variable fluconazole resistance (dose-dependent susceptibility or resistance), and C. krusei is inherently resistant. 3

Address anatomical factors:

• Remove or replace nephrostomy tubes/stents if feasible 1
• Obtain imaging if treatment fails to rule out fungus balls, hydronephrosis, or abscesses 2

For fungus balls or renal/perinephric abscesses:

• Surgical or endoscopic intervention is mandatory – antifungal therapy alone will fail 1, 3
• Add amphotericin B irrigation through nephrostomy tubes (25-50 mg in 200-500 mL sterile water) if present 1

Common Pitfalls to Avoid

Do not use echinocandins (caspofungin, micafungin, anidulafungin) for Candida UTI – they achieve minimal urinary concentrations and are ineffective for lower urinary tract infections. 5, 7

Do not use lipid formulations of amphotericin B – only amphotericin B deoxycholate achieves adequate urine concentrations. 5

Do not use voriconazole, posaconazole, or itraconazole for UTI – these azoles do not achieve sufficient urinary levels. 5, 7

Verify the second urine culture before treating – initial candiduria may represent contamination; confirmation prevents unnecessary treatment. 8

Special Populations

Neutropenic patients and very low-birth-weight infants (<1500g):

• Treat as candidemia with systemic antifungal therapy, not as isolated UTI 1
• Use amphotericin B deoxycholate 1 mg/kg IV daily or fluconazole 12 mg/kg IV/oral daily in neonates 2

Patients with renal failure:

• Fluconazole requires dose adjustment based on creatinine clearance 9
• Amphotericin B carries nephrotoxicity risk; monitor renal function closely 3

Monitoring and Duration

Continue treatment until:

• Symptoms resolve completely AND
• Follow-up urine cultures are negative for Candida species 2, 5
• Standard duration is 2 weeks for uncomplicated cases 1, 2

Obtain follow-up cultures to confirm clearance, especially in high-risk patients. 5

If treatment fails despite appropriate therapy:

• Obtain imaging (CT or ultrasound) to identify anatomical abnormalities, obstruction, or fungus balls 2
• Reassess species identification and antifungal susceptibility 3