Treatment of Candida Overgrowth
The treatment of Candida overgrowth depends critically on distinguishing true invasive infection from colonization, as most Candida isolated from non-sterile sites represents colonization that does not require antifungal therapy. 1, 2
Critical First Step: Determine If Treatment Is Needed
Colonization vs. Infection
- Candida isolated from respiratory secretions (sputum, BAL) almost always represents colonization and should NOT be treated with antifungals, even in ICU patients who are intubated or have chronic tracheostomies 1, 2
- Autopsy studies consistently demonstrate that positive Candida cultures from respiratory secretions have poor predictive value for actual pneumonia—in one study, none of 77 ICU patients who died with positive BAL/sputum cultures had Candida pneumonia at autopsy 2
- Asymptomatic candiduria in males does not require treatment unless the patient is neutropenic or undergoing urologic procedures 3
- Growth of Candida from any site requires clinical correlation with signs and symptoms of actual infection before initiating therapy 1
Treatment by Site of Infection
Invasive/Bloodstream Candidiasis (Candidemia)
For candidemia and invasive candidiasis, echinocandins are now preferred first-line agents for critically ill patients, while fluconazole remains appropriate for less severely ill patients with susceptible species. 1, 4
Initial Therapy Options:
Echinocandins (preferred for critically ill patients): 1, 4
- Caspofungin: 70 mg loading dose, then 50 mg daily
- Micafungin: 100 mg daily
- Anidulafungin: 200 mg loading dose, then 100 mg daily
Fluconazole (for less severely ill patients with susceptible species): 1, 5
Amphotericin B formulations (alternative): 1
- Amphotericin B deoxycholate: 0.5-1 mg/kg IV daily
- Liposomal amphotericin B: 3-5 mg/kg IV daily
Source Control:
- Remove all central venous catheters if feasible—this is particularly critical in non-neutropenic patients and for C. parapsilosis infections 1
Duration:
- Continue therapy for 2 weeks AFTER documented clearance of Candida from bloodstream AND resolution of clinical signs 1
Intra-Abdominal Candidiasis
- Empiric antifungal therapy is indicated for patients with clinical evidence of intra-abdominal infection PLUS significant risk factors: recent abdominal surgery, anastomotic leaks, or necrotizing pancreatitis 1
- Source control with appropriate drainage and/or debridement is mandatory 1, 4
- Antifungal choice follows the same algorithm as candidemia (echinocandins for severe cases, fluconazole for susceptible species in stable patients) 1
- For critically ill patients or health care-associated infections, use echinocandins initially 1, 4
- Duration determined by adequacy of source control and clinical response 1
Urinary Tract Candidiasis
- Asymptomatic candiduria rarely requires treatment—removal of urinary catheters is often sufficient 1
- For symptomatic cystitis or pyelonephritis: 1, 5
- Fluconazole 200 mg daily for 7-14 days (first-line)
- Amphotericin B 0.3-1.0 mg/kg/day for 1-7 days (alternative)
- Flucytosine 25 mg/kg four times daily (for non-albicans species, but resistance emerges rapidly as monotherapy)
- Remove or replace urinary catheters and stents whenever possible 1
Oropharyngeal and Esophageal Candidiasis
Oropharyngeal:
- Fluconazole 200 mg loading dose, then 100 mg daily for at least 2 weeks 1, 5
- Disinfect dentures in addition to antifungal therapy to prevent reinfection 4
Esophageal:
- Fluconazole 200 mg loading dose, then 100-200 mg daily (up to 400 mg based on severity) 1, 5
- Treat for minimum 3 weeks AND at least 2 weeks after symptom resolution 1, 5
Vulvovaginal Candidiasis
- Single dose fluconazole 150 mg PO (92-99% cure rate), OR
- Topical azoles (clotrimazole, miconazole) intravaginally for 1-7 days
Recurrent vulvovaginal candidiasis: 3
- Initial treatment: Fluconazole 150 mg single dose
- Maintenance: Fluconazole 150 mg weekly for 6 months
- Address predisposing factors: uncontrolled diabetes, antibiotic use, immunosuppression
Endocarditis
Initial therapy: 1
- Liposomal amphotericin B 3-5 mg/kg daily ± flucytosine 25 mg/kg four times daily, OR
- High-dose echinocandin (caspofungin 150 mg daily, micafungin 150 mg daily, or anidulafungin 200 mg daily)
Valve replacement is strongly recommended 1
Continue therapy for at least 6 weeks after surgery (longer if perivalvular abscess present) 1
Step-down to fluconazole 400-800 mg daily for susceptible isolates after clinical stability 1
CNS Infections (Meningitis)
Initial therapy: 1
- Amphotericin B deoxycholate 1 mg/kg IV daily, OR
- Liposomal amphotericin B 5 mg/kg daily
- Consider adding flucytosine 25 mg/kg four times daily for salvage therapy
Step-down: Fluconazole 12 mg/kg daily (800 mg) for susceptible isolates 1
Continue until all signs, symptoms, CSF abnormalities, and radiological findings resolve 1
Remove infected CNS devices (ventriculostomy drains, shunts) if possible 1
Special Populations
Neutropenic Patients
- Empiric antifungal therapy appropriate for persistent fever despite 4-6 days of antibacterial therapy 1
- Amphotericin B 0.5-0.7 mg/kg/day or liposomal amphotericin B 3 mg/kg/day 1
- Continue until resolution of neutropenia 1
Neonates
- High-risk neonates in nurseries with >10% invasive candidiasis rates: fluconazole prophylaxis 3-6 mg/kg twice weekly 1
- For treatment, adjust dosing based on gestational age—premature neonates (26-29 weeks) receive same mg/kg dose but every 72 hours for first 2 weeks of life 5
Common Pitfalls to Avoid
- Do not treat positive respiratory cultures alone—this represents colonization in >99% of cases 1, 2
- Do not use fluconazole for C. krusei (intrinsically resistant) or empirically for C. glabrata 3, 6
- Do not use azoles in patients with recent azole exposure—this selects for resistant species 3
- Do not forget source control—drainage, debridement, and catheter removal are as important as antifungals 1, 4
- Do not use amphotericin B as initial therapy for endocarditis when echinocandins are available—toxicity concerns 1