In a patient with an asymptomatic urine culture growing Candida lusitaniae >100,000 colony‑forming units per milliliter from a clean‑catch specimen, what is the appropriate next step in management?

Management of Asymptomatic Candiduria with Candida lusitaniae

In an asymptomatic patient with Candida lusitaniae >100,000 CFU/mL from a clean‑catch urine specimen, do not initiate antifungal therapy; instead, remove any indwelling urinary catheter if present and observe without treatment. 1

Clinical Significance of Asymptomatic Candiduria

• Asymptomatic candiduria almost always represents benign colonization rather than true infection and does not require antifungal treatment in the vast majority of patients. 1

• Treatment of asymptomatic candiduria has never been shown to reduce mortality or improve clinical outcomes in non‑neutropenic, non‑catheterized individuals. 1

• Candiduria progresses to candidemia in fewer than 5% of cases, serving primarily as a marker of overall illness severity rather than a cause of morbidity itself. 1

• Approximately 10–20% of hospitalized individuals carry Candida species in the urinary tract as normal colonizers. 1

First‑Line Management: Remove Predisposing Factors

• Immediate removal of any indwelling urinary catheter is the single most important intervention, resolving candiduria in approximately 50% of asymptomatic cases without the need for antifungal medication. 1

• Discontinue unnecessary broad‑spectrum antibiotics, as these are a major risk factor for the development of candiduria. 1

• Eliminate urinary tract obstruction if present to facilitate clearance. 1

High‑Risk Populations That Require Treatment Despite Lack of Symptoms

Even though your patient is asymptomatic, treatment is indicated if any of the following apply:

• Neutropenic patients with persistent unexplained fever and candiduria, due to heightened risk of disseminated candidiasis. 1

• Very low birth‑weight neonates (generally <1500 g) because of high propensity for invasive candidiasis. 1

• Patients scheduled for urologic procedures or instrumentation within the next several days, given the potential for procedure‑related candidemia. 1

• Patients with urinary tract obstruction that cannot be promptly relieved, as obstruction sustains fungal persistence. 1

Monitoring Strategy for Low‑Risk Asymptomatic Patients

• Observe without antifungal therapy for asymptomatic, non‑immunocompromised individuals without an indwelling catheter and without recent urologic manipulation. 1

• Monitor for the emergence of urinary symptoms (dysuria, increased frequency, urgency, suprapubic pain, fever); their appearance should trigger reassessment for antifungal treatment. 1

• Development of flank pain, fever >38.3°C, or other systemic manifestations should raise suspicion for Candida pyelonephritis and prompt immediate treatment. 1

Species‑Specific Considerations for Candida lusitaniae

• Candida lusitaniae is generally susceptible to fluconazole but historically displays resistance to amphotericin B. 2

• If treatment becomes indicated (e.g., patient develops symptoms or falls into a high‑risk category), fluconazole 200 mg orally once daily for 14 days is the preferred first‑line regimen for fluconazole‑susceptible isolates. 1

• The ability of C. lusitaniae to form biofilms and its rapid mutation rate make treating established infections difficult; this underscores the importance of removing indwelling catheters promptly. 3

Critical Pitfalls to Avoid

• Do not prescribe antifungal therapy reflexively for asymptomatic candiduria in otherwise healthy individuals, diabetic patients without additional high‑risk features, or elderly patients lacking other indications. 1

• Do not rely on colony counts or pyuria to differentiate colonization from infection, especially in catheterized patients; these parameters are unreliable. 1

• Avoid using echinocandins (caspofungin, micafungin, anidulafungin) or newer azoles (voriconazole, posaconazole) for urinary Candida infections, as these drugs achieve insufficient concentrations in urine. 1

• In male patients, candiduria should not be automatically dismissed as simple colonization; evaluation for possible prostatitis is warranted if urinary symptoms develop. 1

When to Reassess and Initiate Treatment

• If the patient develops urinary symptoms (dysuria, frequency, urgency, suprapubic pain) or systemic signs (fever, flank pain), obtain renal or bladder imaging to exclude obstruction, fungal balls, or perinephric abscesses. 1

• For symptomatic Candida cystitis, fluconazole 200 mg orally once daily for 14 days is the treatment of choice; this recommendation is based on the only randomized, double‑blind, placebo‑controlled trial demonstrating clinical efficacy. 1

• For symptomatic Candida pyelonephritis, increase fluconazole dosing to 200–400 mg (3–6 mg/kg) orally once daily for 14 days, using the higher 400‑mg dose when upper‑tract involvement is confirmed. 1