Opportunistic Fungal Infections (2) Flashcards
Opportunistic fungal pathogens cause local symptoms in previously healthy symptom but seldum dangerous symptoms in certain predispositions, what are these?
- prolonged neutropenia
- uncontrolled HIV or diabetes
- profound T cell suppression
In order to effectively treat an opportunistic fungal infection, what is key?
treating the underlying problem
What enables crypto infections?
reduced CMI
What is the presentation of crypto?
LATE presentation with meningitis and skin nodules or pulmonary symptoms
How do you diagnose a crypto infection?
biopsy, CSF, CRAG
india ink
What is the treatment for crypto?
combos of azoles and amphotericin B
What are the four presentations of aspergillosis?
- ABPA
- Aspergilloma
- CNPA
- Invasive
What causes ABPA presentation of aspergillosis?
hypersensitivity reaction to infection complicating asthma or CSF
What is the treatment for ABPA?
itraconazole, sinus surgery, xolair
only presentation treated with oral steroids
What is an aspergilloma?
fungus ball complicating cavitary lung disease
How would you diagnose an aspergilloma?
appears as an air crescent on CT scan
What is the treatment for aspergillomas?
itraconazole and or surgery
What does CNPA appear like?
TB
How is CNPA diagnosed?
air crescent on CT scan
-needle aspirate lung fluid for microscopy
How does invasive aspergillosis present?
respiratory distress with history of immunosuppression
What is the specific sign of invasive aspergillosis on CT?
halo sign
What is the treatment for CNPA and invasive aspergillosis?
voriconazole + ampho B
prognosis is poor
What causes this:
“-very rare deadly invasive vasculitis caused by environmental mold, causes infararction
-invades brain from sinuses”
caused by mucor or rhizopus
mucormycosis
What are the predispositions that can lead to mucormycosis infection?
uncontrolled diabetes, iron overload, immunosuppression
How would you diagnose an infection with mucormycosis?
biopsy - nonseptate hyphate branches at rt angles
What is the treatment and prognosis for a mucormycosis infection?
amphotericin B and aggressive surgical removal of diseased tissue - prognosis is poor
Is fusarium ubiquitous or only found in certain locations?
ubiquitous
What are the three presentations of fusarium?
- mycotoxicosis
- local infection
- disseminated infection
how do you get mycotoxicosis?
contaminated grain
How do you get local infection with fusarium?
burns, prosthetics, contaminated contact solution
How would a patient contract a deadly disseminated infection from fusarium?
prolonged neutropenia, HSCT recipients
How do you treat a fusarium infection?
surgery, ampho B, voriconazole
Does fusarium spread lymphatically or hematogeneously?
through the bl0o0o0od - fungemia
How do you diagnose fusarium infection?
blood culture and histology
(don’t take positive results so seriously though since it is so ubiquitous)
-appears bannana shaped
What is the prognosis of a fusarium infection?
poor prognosis
How would you distinguish a fusarium from an aspergillosis infection?
if yeast present –> fusarium
aspergillus doesn’t have a yeast form
What fungal infection is the most innately resistant to drugs?
fusarium
