Candida species

• Most common medically-important genus of yeast

Microbiology

• Budding yeast

Organisms

• C. albicans
• C. dubliniensis
• C. glabrata: Fluconazole-resistant
• C. tropicalis
• C. parapsilosis
• C. krusei
• C. auris

Clinical Presentation

• Most common: mouth, vagina, skin
• In immunocompromised, ICU, IVDU, or TPN patients: Esophagus, blood, CNS, endophthalmitis
• Less common: joint
• IVDU: endocarditis

Investigations

• Urine culture if concern for cystitis
• Blood culture
  • Never ignore candidemia!
  • Requires an ophthalmology consult to rule out endophthalmitis (1-3% of cases)
  • Echocardiogram if IVDU or prosthetic valve
• Germ tube test (GTT)
  • If positive, indicates C. albicans or C. dubliniensis
  • Identifies fluconazole-sensitive Candidae

Species and Resistance

Species	Resistance pattern
C. albicans	Generally fluconazole-susceptible
C. dubliniensis	Generally fluconazole-susceptible
C. parapsilosis	Generally fluconazole-susceptible
C. glabrata	Often fluconazole resistant, or dose-dependent
C. tropicalis	Generally fluconazole-susceptible
C. krusei	Inherent fluconazole resistance
C. lusitaniae	Often amphotericin resistant but fluconazole-susceptible

• See also Antifungal spectrum of activity and Pharmacology of Systemic Antifungal Agents, CID 2006

Treatment

• First-line:
  • Remove lines!
  • GGT positive: fluconazole for 2 weeks after first negative blood culture
  • GGT negative: move to second-line therapies
• Second-line: micafungin, then amphotericin B (last choice)
• Endophthalmitis: extend course to 4 weeks
• Failure of therapy: double-check for endophthalmitis