Introduction to Pathogenic Fungi

Question 1

Coccidiomycosis…how it enters the body, how to spreads, where its found, and clinic manifestation

Answer 1

Dimorphic mold in the soil and spherules containing endospores in the tissue
Enters body through inhalation arthroconidia from soil
Arthroconidia germinate in alveoli into spherules, where it generates sportes through division til rupture
Fever, non-productive cough
SW US

Question 2

Histoplasmosis, ecology, geographic, CM, and what it looks like

Answer 2

Dimorphic mold in environment and yeast in tissue
Lives in soil, enriched by bird or bat manure
Mississippi/Ohio River Valleys
Fever, non-productive cough
Yeast in macrophages

Question 3

Blastomycosis, geographic, CM, what it looks like, ecology

Answer 3

Dimorhpic 
Lives in soil and decaying vegetation in association with bodies of water 
Mississippi/mizzou valleys 
Fever, cough with sputum
Thick walled yeast with broad based buds

Question 4

Candida structure and where normally found

Answer 4

Psuedohyphae

Mucocutaneous surfaces

Question 5

Candidiasis results from, example of cutaenous/subcutaenous infection, and systemic

Answer 5

Immunosuppression, diabetes, trauma, AB use
Oral Thrush
GI, endophthalmitis, endocaditis

Question 6

How to ID Candida albicans

Answer 6

Gram neg will show no germ tube production, C albicans will

Question 7

Presentation of candidiasis

Answer 7

Angular chelitis and white on the tongue…forms psuedomembranes composed of cells and pseudohyphae

Question 8

Pneumocystis jiroveci, when is it found, how are samples obtained, and what is it characterized by

Answer 8

Opportunistic in HIV patients
Cannot be cultured
BAL wash or induced sputum
Characterized by alveoli filled with desquamated alveolar cells, monocytes, organisms, and fluid which produces a foamly, honeycombed appearance

Question 9

Cryptococcus neoformans biology

Answer 9

Encapsulated yeast

Common soil fungus associated with roosting sites of pigeons

Question 10

Risk factors for cryptococcus

Answer 10

HIB pts with low CD4
Immune suppression
Pigeon Exposrue

Question 11

Virulence factors of cryptococcus and how it enters

Answer 11

Polysach capsule
Enters via inhaled spores
Causes mild lung infection and often localizes to CNS

Question 12

Aspergillus virulence factors,

Answer 12

Thermotolerant, gliotoxin inhibits phagocytic killing

Elastases, proteinases, phospholipases

Question 13

Aspergillus appearance

Answer 13

45 degree angle septate hyphase