L61 Flashcards
What 2 bugs cause mucormycosis?
Mucor
Rhizopus
What infections are the result of mucormycosis?
Rhinocerebral zygomycosis
Pulmonary
Walk through the pathogenesis of rhinocerebral zygomycosis
Inhale mucor/rhizopus spores 1st infection @ sinuses Invade BVs --> necrosis Invade eye Direction access to brain
Describe the shape of fungi for mucormycosis
Broad
No septa
Branch at right angles
What is the clinical presentation of mucormycosis
Sinus symptoms + necrotic lesions
- Ethmoid sinus involvement
Pulmonary = pulmonary mucormycosis
What are you look for on CT and histo for pulmonary mucormycosis
Histo = coag necrosis CT = dense infarction w/ halo
Treat mucormycosis
Amphoterin B
Surgical debridement of necrotic areas
What bug causes cryptococcosis
Cryptococcus neoformans
What are the 3 symptoms of a cryptococcal opportunistic infection?
Pna
Meningitis
Fever
Specifically, which IC pts are at highest risk for a cryptococcal infection?
T cell compromised
- On steroids
- Transplant
- HIV
Explain cryptococcal pathogenesis
Inhale yeast Replicate in lung Progressive infection b/c IC Spread and cross BBB Further replication in gelatinous lesion
What is a characteristic VF for cryptococcal neoformans
HUGE capsule - doesn’t stain well for this reason
Glucuronoxylomannan
X phagocytosis
What stains do you use for cryptococcus? How do they look on stain?
PAS GMS Mucicarmine silver INDIA INK - Stain LIGHT - Huge halo around nucleus b/c of capsule
Which enzyme helps with melanin production for cryptococcus?
Phenoloxidase
Make melanin b/c inhibits O2 killing by host
Treat cryptococcus
Start: amphotericin B + 5 FC
(Just to get infection under control b/c nephrotoxic)
Continue: fluconazole
