What is the treatment for a urinary tract infection (UTI) caused by yeast with Diflucan (fluconazole)?

Treatment of Urinary Tract Infection Caused by Yeast with Fluconazole

For a urinary tract infection caused by yeast, fluconazole 200 mg (3 mg/kg) daily for 2 weeks is the recommended treatment of choice. 1, 2

Treatment Algorithm Based on Candida Species

• For fluconazole-susceptible Candida species (most common), oral fluconazole 200 mg (3 mg/kg) daily for 2 weeks is strongly recommended 1
• For fluconazole-resistant C. glabrata:
  • Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days OR
  • Oral flucytosine 25 mg/kg 4 times daily for 7-10 days 1, 2
• For C. krusei infections:
  • Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days 1

Rationale for Fluconazole Use

• Fluconazole is the preferred agent because it achieves high urinary concentrations, has an oral formulation, and demonstrates proven effectiveness 2, 3
• FDA-approved for treatment of Candida urinary tract infections 4
• Clinical studies show efficacy rates of 85-88% for fluconazole in treating urinary candidiasis 5, 6
• Fluconazole causes more rapid clearance of funguria than catheter replacement alone 7

Important Clinical Considerations

• Removal of indwelling bladder catheters, if present, is strongly recommended as part of treatment 1, 8
• Elimination of urinary tract obstruction is strongly recommended if present 1
• For patients with nephrostomy tubes or stents, consider removal or replacement if feasible 1, 2

Management of Special Situations

• For fungus balls (obstructing mycelial masses):
  • Surgical or endoscopic removal is strongly recommended in adults 1
  • Antifungal treatment as noted above for cystitis or pyelonephritis 1
  • If nephrostomy tubes are present, irrigation with amphotericin B deoxycholate (25-50 mg in 200-500 mL sterile water) may be beneficial 1

Treatment Alternatives for Resistant Organisms

• For fluconazole-resistant species (particularly C. glabrata and C. krusei):
  • Amphotericin B deoxycholate bladder irrigation (50 mg/L sterile water daily for 5 days) may be useful for treatment of cystitis 1, 2
  • For pyelonephritis due to resistant organisms, amphotericin B deoxycholate 0.5-0.7 mg/kg daily with or without flucytosine may be required 1

Common Pitfalls to Avoid

• Avoid using echinocandins or other azoles (besides fluconazole) for lower urinary tract infections as they have minimal excretion into urine 9, 3
• Avoid lipid formulations of amphotericin B as they do not achieve adequate urine concentrations 2, 1
• Do not rely solely on colony count in urine to differentiate between colonization and infection, especially when a catheter is present 2
• Remember that asymptomatic candiduria often represents colonization rather than infection and may not require treatment in most patients 8, 3

Monitoring and Follow-up

• Monitor for clinical improvement and obtain follow-up urine cultures to confirm clearance of infection 2
• Treatment should continue until symptoms have resolved and urine cultures no longer yield Candida species 2
• For persistent infection despite appropriate therapy, consider imaging to rule out anatomical abnormalities or fungus balls 2