In an adult without known fluconazole resistance, is itraconazole an appropriate first‑line treatment for Candida cystitis?

Itraconazole is NOT Appropriate for Candida Cystitis

Itraconazole should not be used as first-line treatment for Candida cystitis in adults without known fluconazole resistance; fluconazole is the standard of care due to superior pharmacokinetics, better tolerability, and high urinary concentrations of active drug. 1

Why Itraconazole Fails as First-Line Therapy

The Infectious Diseases Society of America explicitly states there is little role for itraconazole in treating Candida urinary tract infections, given fluconazole's similar antifungal spectrum, ease of administration, superior pharmacokinetics, and better tolerability. 1

Pharmacologic Disadvantages of Itraconazole

• Itraconazole does not achieve adequate urinary concentrations compared to fluconazole, which is critical for eradicating Candida from the urinary tract. 2
• Fluconazole attains high concentrations of active drug in urine, ensuring effective pathogen eradication—a property itraconazole lacks. 2
• The poor and variable absorption of itraconazole formulations further limits its utility in urinary infections. 3

First-Line Treatment: Fluconazole

For symptomatic Candida cystitis caused by fluconazole-susceptible species, fluconazole 200 mg (≈3 mg/kg) orally once daily for 14 days is the preferred regimen. 1, 2, 4, 5, 6

Supporting Evidence

• This recommendation is based on randomized controlled trial data demonstrating efficacy in symptomatic cystitis. 2
• Fluconazole remains standard therapy for Candida urinary infections on the basis of abundant data from well-designed clinical trials. 1
• For symptomatic pyelonephritis, increase the dose to fluconazole 200–400 mg (≈3–6 mg/kg) orally once daily for 14 days. 1, 2, 7, 4

Essential Non-Pharmacologic Management

Immediate removal of any indwelling urinary catheter is the single most important intervention, resolving candiduria in approximately 50% of cases without antifungal therapy. 1, 2, 7

• Catheter removal should be the first step before initiating antifungal treatment. 1
• Elimination of urinary tract obstruction is mandatory for successful treatment. 7
• Discontinuation of unnecessary broad-spectrum antibiotics reduces risk of persistent candiduria. 2

When Fluconazole Cannot Be Used

If fluconazole is contraindicated due to resistance, allergy, or treatment failure, alternative agents include:

• For fluconazole-resistant C. glabrata: Amphotericin B deoxycholate 0.3–0.6 mg/kg IV daily for 1–7 days, with or without oral flucytosine 25 mg/kg four times daily. 1, 2, 7, 4
• For intrinsically fluconazole-resistant C. krusei: Amphotericin B deoxycholate 0.3–0.6 mg/kg IV daily for 1–7 days. 1, 2, 7
• Oral flucytosine 25 mg/kg four times daily for 7–10 days as monotherapy may be considered when amphotericin B is unsuitable (weaker recommendation). 2

Critical Pitfalls to Avoid

• Do not use echinocandins for urinary Candida infections—they achieve inadequate urine concentrations and are ineffective for cystitis or pyelonephritis. 2, 7
• Do not use lipid formulations of amphotericin B for Candida pyelonephritis—treatment failures are well-documented. 7
• Do not treat asymptomatic candiduria reflexively—most cases represent benign colonization and treatment does not reduce mortality. 2
• Do not assume all Candida species are fluconazole-susceptible—C. glabrata resistance is common and C. krusei is intrinsically resistant. 7

When to Suspect Treatment Failure

• If urinary symptoms persist beyond 48–72 hours, obtain renal or bladder imaging (ultrasound or CT) to exclude obstruction, fungal balls, or perinephric abscesses. 2
• Presence of fungal balls or casts in the renal pelvis or bladder mandates surgical intervention in addition to systemic antifungal therapy. 1, 2, 7
• In cases of recurrent candiduria after appropriate treatment, evaluate for underlying urologic abnormalities such as strictures, stones, or prostatic disease. 2