What is the first-line treatment for a patient with candiduria (yeast in urine) and urinary frequency?

Treatment of Candiduria with Urinary Frequency

For symptomatic candiduria with urinary frequency, oral fluconazole at a dosage of 200 mg (3 mg/kg) daily for 2 weeks is the first-line treatment for fluconazole-susceptible Candida species. 1, 2

Diagnostic Approach

• Candiduria with symptoms like frequency suggests cystitis rather than mere colonization, requiring treatment 1
• Diagnostic tests on urine often cannot differentiate colonization from infection, so symptoms guide treatment decisions 1
• Imaging (ultrasound or CT) may be helpful to rule out structural abnormalities, hydronephrosis, or fungus ball formation 1

Treatment Algorithm

First-line therapy:

• Fluconazole 200 mg (3 mg/kg) daily for 2 weeks 1, 2
  • Preferred due to excellent urinary concentration of active drug
  • Available as oral formulation
  • Achieves high urine levels exceeding MIC for most Candida isolates 1
  • Some sources suggest a 200-mg loading dose followed by 100 mg/day for at least four days 3

For fluconazole-resistant species (especially C. glabrata and C. krusei):

• Amphotericin B deoxycholate (AmB-d) 0.3-0.6 mg/kg daily for 1-7 days 1
• Oral flucytosine 25 mg/kg 4 times daily for 7-10 days 1
• AmB-d bladder irrigation may be considered for refractory cases 1

Special Considerations

Species-specific approach:

• C. albicans (most common): Typically susceptible to fluconazole 1, 4
• C. glabrata (accounts for ~20% of urine isolates): Often requires alternative therapy due to fluconazole resistance 1

Important clinical pearls:

• Eliminate predisposing factors (e.g., indwelling catheters, antibiotics) as this alone may clear candiduria in almost 50% of patients 5
• Echinocandins and other azoles (besides fluconazole) have minimal excretion into urine and are generally ineffective for treating Candida UTI 1, 5
• Lipid formulations of amphotericin B do not achieve adequate urine concentrations and should not be used 1

Treatment duration:

• Standard duration is 2 weeks for cystitis 1, 2
• Treatment should continue until symptoms have resolved and urine cultures no longer yield Candida species 1

Common Pitfalls to Avoid

• Treating asymptomatic candiduria in patients without risk factors for dissemination 1, 2
• Using antifungal agents with poor urinary excretion (echinocandins, voriconazole) for lower urinary tract infections 1, 5
• Overlooking the possibility of disseminated candidiasis in high-risk patients with candiduria 2
• Failing to remove predisposing factors such as indwelling catheters 5