11 - Fungal Infections Flashcards
What are some types of infections associated w/ candida?
- Mucosal candidiasis (oropharyngeal, esophageal, vulvovaginitis)
- Candidemia
- Invasive/acute disseminated candidiasis involving visceral site or organ
- Hepatosplenic/chronic disseminated candidiasis (most often in hematologic malignancy, recent neutropenia)
What are the most common candida species associated w/ infections?
- Albicans
- Glabrata
- Parasilosis
- Tropicalis
- Krusei
Which candida species are most resistant to anti-fungals?
Krusei > glabrata > albicans
What can fluconazole prophylaxis cause?
Increased occurrence of non-albicans candidiasis
What is candida auris?
Emerging healthcare-associated pathogen w/ multi-drug resistance
What are some risk factors for candidiasis?
- ICU > 4 days, septic shock, broad-spectrum antibiotics
- Central venous catheter (CVC)
- Liver transplant, severe pancreatitis
- Peritoneal-dialysis peritonitis
- Recent GI surgery!
- Immunocompromised (hematologic malignancy, chemotherapy, transplant suppression, corticosteroids)
How do corticosteroids suppress the immune system?
Affect the function of cells (neutrophils don’t function as normal so immune system doesn’t function as normal)
Why are diabetics immunocompromised?
High levels of glucose make neutrophils not function properly
How will candida species appear on a microscope?
Budding yeast w/ hyphae or pseudo-hyphae
What test can you do for C. albicans?
Germ tube test (positive test = C. albicans)
What is used to diagnose candidiasis?
- Microscopic visualization
- Culture (60-80% positive in candidemia, 50% in invasive infection)
- Histopathology for deep-seated infections & mold infections
- Triazole susceptibility testing
What are the clinical signs and sx of candidiasis?
- Endophthalmitis of choroid and retina, fluffy yellow-white lesions +/- viritis (intraocular inflammation) or retinal hemorrhages
- Skin lesions w/ pustules on erythematous base
- Hepatosplenic micro-abscesses (presents w/ persistent fever, RQ pain, increased alkaline phosphatase)
What is C. parapsilosis associated with?
Line infection/ catheter (tx is to remove catheter)
What is the prognosis of candidemia?
- 30-40% mortality (lower for C. parapsilosis)
- 3x increase in mortality when antifungal therapy delayed > 12-24 h
What else should be done alongside antifungal therapy for candidemia in non-neutropenic px?
Remove and/or replace CVC if the source
What are the antifungal options for candidemia in non-neutropenic px?
- Echinocandin (preferably micafungin)
- For non-critically ill, non-invasive w/o risk factors for fluconazole resistance – flucon (800 mg PO/IV load, 400 mg q24h
- [Ampho B]
- Consider PO step-down from IV to flucon (400 mg q24h) after 5-7 days if sx resolved, clinically stable, flucon-susceptible isolate and negative blood culture