Fungal Infections

Question 1

Candidiasis

Answer 1

• Part of normal flora of skin, mouth, and GI tract.
• Occur as yeast and pseudohyphal forms.
• Grows best on warm, moist surfaces.

Question 2

Candidiasis Virulence

Answer 2

• Adhesins (binding)
• Catalases that aid intracellular survival by resisting phagocyte oxidative killing.
• Adenosine blocks neutrophil degranulation and oxygen radical production.
• Ability to grow as a biofilm on devices.

Question 3

Candidiasis Findings

Answer 3

• Neutrophil and macrophage phagocytosis mediated by TH17 response is first line defense.
• Superficial curdy white patches that are easily detached.

Question 4

Cryptococcus neoformans

Answer 4

• Encapsulated yeast whose capsule stains bright red with mucicarmine and in CSF it is negatively stained with India Ink.

Question 5

Cryptococcus Neoformans Virulence

Answer 5

• Capsular polysaccharide inhibits phagocytosis, leukocyte migration, and inflammatory cell recruitment.
• Laccase, an enzyme that induces formation of a melanin-like pigment with antioxidant properties.

Question 6

Cryptococcus Neoformans Findings

Answer 6

• In healthy people it can form solitary pulmonary granulomata.
• Opportunistic Infection in immunocompromised, the major lesion in such involves the CNS, occurring as gray matter cysts called (“soap bubble lesions”)

Question 7

Aspergillosis

Answer 7

• Mold transmitted by air-horned conidia.

- Grows as SEPTATED Hyphae branching at acute angles.

Question 8

Aspergillosis Virulence

Answer 8

• Adhesion to albumin, surfactant, and ECM proteins.

- Antioxidant defenses, phospholipases and proteases and AFLATOXIN.

Question 9

Zygomycosis

Answer 9

• Opportunistic in neutropenics and diabetics.
• Non-septated with right-angle branching.
• Site of infection depends on whether spores are inhaled or ingested.