What is the appropriate treatment for a patient with yeast in their urine, potentially indicating an underlying condition such as diabetes or immunocompromised status?

Management of Yeast in Urine

Most patients with yeast in their urine do not require antifungal treatment, as candiduria typically represents benign colonization rather than infection. 1

Initial Assessment: Determine If Treatment Is Needed

The presence of yeast in urine must be evaluated based on symptoms and risk factors, not simply treated reflexively. 1

Asymptomatic Candiduria (No Treatment Required)

For patients without symptoms or high-risk features:

• Observation alone is appropriate for asymptomatic candiduria in most patients, including those with diabetes mellitus or mild immunosuppression. 1, 2
• Remove predisposing factors such as indwelling urinary catheters (clears candiduria in ~50% of cases) and discontinue unnecessary broad-spectrum antibiotics. 1, 2
• Candiduria progresses to candidemia in less than 5% of cases and treatment does not reduce mortality. 2

High-Risk Patients Requiring Treatment Despite Being Asymptomatic

Treatment is mandatory for asymptomatic candiduria in these specific populations:

• Neutropenic patients with persistent unexplained fever and candiduria 1, 2
• Very low birth weight neonates (at high risk for disseminated candidiasis) 1, 2
• Patients undergoing urologic procedures or instrumentation (high risk for candidemia) 1, 3
• Severely immunocompromised patients with fever and urinary tract obstruction 4, 2

For these high-risk patients undergoing urologic procedures: fluconazole 200-400 mg (3-6 mg/kg) daily or amphotericin B deoxycholate 0.3-0.6 mg/kg daily for several days before and after the procedure. 1, 3

Treatment Algorithm for Symptomatic Candiduria

Symptomatic Cystitis (Urinary Frequency, Dysuria, Suprapubic Pain)

First-line treatment: Fluconazole 200 mg (3 mg/kg) orally daily for 2 weeks for fluconazole-susceptible Candida species (C. albicans, C. tropicalis, C. parapsilosis). 1, 4, 3

• Fluconazole achieves high urinary concentrations in active form, making it superior to all other antifungals for lower urinary tract infections. 4, 3
• C. albicans is typically fluconazole-susceptible, while C. glabrata and C. krusei are often resistant. 4

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

• Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days 1, 4
• Oral flucytosine 25 mg/kg four times daily for 7-10 days (alternative option) 1, 4

Candida Pyelonephritis (Fever, Flank Pain, Systemic Symptoms)

First-line treatment: Fluconazole 200-400 mg (3-6 mg/kg) orally daily for 2 weeks for fluconazole-susceptible organisms. 1, 3

For fluconazole-resistant C. glabrata:

• Amphotericin B deoxycholate 0.5-0.7 mg/kg daily with or without flucytosine 25 mg/kg four times daily for 2 weeks 1
• Flucytosine alone at 25 mg/kg four times daily for 2 weeks is an alternative. 1

Fungus Balls (Obstructing Masses in Renal Collecting System)

• Surgical or endoscopic removal is mandatory in non-neonates. 1, 3
• Adjunctive systemic therapy: Fluconazole 200-400 mg (3-6 mg/kg) daily 1
• Alternative: Amphotericin B deoxycholate 0.5-0.7 mg/kg daily with or without flucytosine 25 mg/kg four times daily 1
• If access to renal collecting system is available, irrigation with amphotericin B 50 mg/L of sterile water can be used as adjunct. 1
• Continue treatment until symptoms resolve and urine cultures are negative for Candida. 1

Suspected Disseminated Candidiasis with Candiduria

• Treat as candidemia with systemic antifungal therapy (not limited to urinary-specific agents). 1
• Consider imaging (ultrasound or CT) to rule out structural abnormalities, hydronephrosis, or fungus ball formation. 4

Critical Pitfalls to Avoid

Do NOT Use These Agents for Candida UTI:

• Echinocandins (caspofungin, micafungin, anidulafungin) achieve minimal urinary concentrations and are ineffective for lower urinary tract infections. 4, 3
• Lipid formulations of amphotericin B do not achieve adequate urine concentrations. 4
• Voriconazole and other azoles (besides fluconazole) have minimal urinary excretion. 4, 3

Do NOT Treat:

• Asymptomatic candiduria in otherwise healthy patients (including those with diabetes alone or advanced age alone). 1, 2
• Treatment of asymptomatic candiduria does not prevent complications or reduce mortality. 2

Do NOT Overlook:

• Possibility of disseminated candidiasis in high-risk patients (neutropenic, neonates, severely immunocompromised). 4, 2
• Need for catheter removal as a primary intervention before considering antifungal therapy. 2

Treatment Duration

• Standard duration: 2 weeks for both cystitis and pyelonephritis. 1, 4, 3
• Continue therapy until symptoms resolve and urine cultures are negative for Candida species. 1, 3