What is the recommended treatment course for a patient with a Candida urinary tract infection (UTI) and an indwelling catheter?

Treatment of Candida UTI in Catheterized Patients

Remove the indwelling urinary catheter if feasible, and treat symptomatic patients with oral fluconazole 200 mg daily for 2 weeks for fluconazole-susceptible organisms. 1

Catheter Management: The Critical First Step

Catheter removal is strongly recommended and often sufficient to clear candiduria without antifungal therapy. 1 This is the single most important intervention, as:

• Removal of an indwelling bladder catheter, if feasible, carries a strong recommendation from the Infectious Diseases Society of America 1
• Catheter replacement alone results in 87-93% clearance of urinary findings at 8 weeks in asymptomatic patients 2
• If the catheter has been in place for ≥2 weeks at onset of UTI, it should be replaced to hasten symptom resolution and reduce risk of subsequent infection 3, 4

Important caveat: Most candiduria in catheterized patients represents colonization, not infection. 5, 6 Antifungal therapy is not indicated for asymptomatic candiduria—catheter removal alone is often sufficient. 1

When to Treat with Antifungals

Treat with antifungal agents only when patients have:

• Symptomatic cystitis (dysuria, urgency, suprapubic pain) 1
• Pyelonephritis symptoms (fever, flank pain) 1
• Neutropenia with persistent unexplained fever 1
• Immunocompromised status without a catheter (may indicate disseminated candidiasis) 1

Antifungal Treatment Algorithm

For Fluconazole-Susceptible Organisms (C. albicans, most isolates):

First-line: Oral fluconazole 200 mg (3 mg/kg) daily for 2 weeks 1

• Fluconazole is the drug of choice, achieving high urine concentrations in its active form 1, 5
• This was proven effective in the only randomized, double-blind, placebo-controlled trial for candiduria 1
• Available orally, making outpatient treatment feasible 5

For Fluconazole-Resistant C. glabrata:

Option 1: Amphotericin B deoxycholate 0.3–0.6 mg/kg daily for 1–7 days 1

Option 2: Oral flucytosine 25 mg/kg four times daily for 7–10 days 1

Option 3: Amphotericin B deoxycholate bladder irrigation (50 mg/L sterile water daily for 5 days) may be useful for cystitis due to fluconazole-resistant species 1

For C. krusei (intrinsically fluconazole-resistant):

Amphotericin B deoxycholate 0.3–0.6 mg/kg daily for 1–7 days 1

Treatment Duration

• Standard duration: 2 weeks for symptomatic lower UTI 1
• Upper tract involvement: 2 weeks for fluconazole-susceptible organisms, potentially longer for resistant species 1
• Pyelonephritis: Fluconazole 200–400 mg (3–6 mg/kg) daily for 2 weeks 1

Critical Pitfalls to Avoid

Do not use echinocandins or newer azoles (voriconazole, posaconazole) for Candida UTI—they fail to achieve adequate urine concentrations and are ineffective for urinary tract infections. 5, 6 This is a common error, as these agents are excellent for invasive candidiasis but inappropriate for UTI.

Do not treat asymptomatic candiduria in catheterized patients unless specific high-risk conditions exist (neutropenia, planned urologic procedures). 1 Overtreatment promotes resistance and provides no benefit.

Obtain urine culture before treatment to identify species and guide therapy, as colony counts cannot differentiate infection from colonization in catheterized patients. 1

Special Considerations for Pyelonephritis

If upper tract involvement is suspected:

• Eliminate urinary tract obstruction (strong recommendation) 1
• Consider removal or replacement of nephrostomy tubes or stents if present 1
• Use higher fluconazole doses: 200–400 mg daily for 2 weeks 1
• Imaging (ultrasound or CT) is helpful to identify fungus balls, abscesses, or emphysematous pyelonephritis 1

Fungus balls require surgical intervention—antifungal agents alone will not clear aggregations of mycelia and yeasts causing obstruction. 1

Candidemia vs. Candiduria

If candidemia is suspected or confirmed (not just candiduria):

• Remove all catheters (urinary and central venous) 1
• Treat for 14 days after the last positive blood culture 1
• Use fluconazole 400 mg daily for hemodynamically stable patients with susceptible organisms 1
• Use echinocandins or amphotericin B for unstable patients or azole-resistant species 1

This distinction is crucial: candidemia requires aggressive systemic treatment and catheter removal, while isolated candiduria in a catheterized patient often requires only catheter management. 1