Aspergillus fungus and other fungal infections

Question 1

Describe gross features of aspergillus fungal lesion

Answer 1

necrotizing fungal “target lesion” with pale center
and hemorrhagic border (↑) invading across the
major fissure and into vessels.

Question 2

Can aspergillus spread to other organs?

Answer 2

Yes it can have hematogenous dissemination to other organs because it does invade into blood vessels

Question 3

Describe microscopic features of aspergillus

Answer 3

5-10 micrometers thick branching septate hyphae

Question 4

Pathophysiologically, how do aspergillosis target lesions form?

Answer 4

TH2-mediated immune response lead to allergic bronchopulmonary aspergillosis with acute features similar to asthma and chronic changes of obstructive lung disease

Question 5

Where are aspergillosis lesions commonly found?

Answer 5

It can colonize pre-existing cavitaty lesions in TB, bronchiectasis, abscess, and infarct

Question 6

Which 2 pathologic lesions can be caused by Candida Albicans tropicalis?

Answer 6

1.Hematogenous milliary abscesses with associated necrotizing focal pneumonitis
2. Bronchogenic pneumonia with abscess formation

Question 7

A necrotising bronchopneumonia with eventual hemorrhagic infarcts is caused by which pathogen?

Answer 7

Aspergillus fumigatus niger

Question 8

Necrotizing bronchopneumonia with prominent vascular invasion and hemorrhagic infarction and hemoptysis is caused by which pathogen?

Answer 8

Mucor (phycomycosis)

Question 9

Which pathogen causes Alveolar mucoid exudate with organisms and mild foreign body (occasionally tuberculoid) granulomatous reaction

Answer 9

Cryptococcus neoformans

Question 10

Which pathogen causes Tuberculoid granulomatous and necrotizing bronchopneumonia

Answer 10

Histoplasma capsulatum

Question 11

which pathogen causes Puriform and bronchopneumonia with abscess formation, chronic
cavernous bronchopneumonia

Answer 11

Blastomyces dermatitidis

Question 12

Explain how cryptococcus neoformans look like microscopically

Answer 12

Cryptococcus
neoformans organisms that have a large polysaccharide
capsule, giving the appearance of a clear zone around a
faint, central round nucleus

Question 13

What is the functions of the cryptococcus neoformans capsule?

Answer 13

This capsule inhibits
inflammatory cell recruitment and macrophage
phagocytosis.

Question 14

What causes cryptococcal infection with pneumonia

Answer 14

Cryptococcal infection with pneumonia can occur after
inhalation of aerosols from soils contaminated with bird
droppings

Question 15

Where does cryptococcus normally disseminate to?

Answer 15

the central
nervous system, often producing meningitis in
immunocompromised individuals

Question 16

What type of inflammatory rxn can occur with cryptococcal infections?

Answer 16

Can range from suppurative to granulomatous