Fungal Infections 27.11.23

Question 1

Are fungi eukaryotic or prokaryotic?

Answer 1

Eukaryotic

Question 2

What is fungi cell walls made of?

Answer 2

Chitinous cell wall

Question 3

Is fungi heterotrophic (an organism that eats other plants or animals for energy and nutrients)?

Answer 3

Yes

Question 4

How does fungi move?

Answer 4

Move by means of growth or through the generation of spores, which are carried through air or water

Question 5

Define yeast

Answer 5

Yeasts are small single celled organisms that divide by budding

Question 6

What do moulds form?

Answer 6

Moulds form multicellular hyphae and spores

Question 7

Can fungi exist as both yeast and moulds swithcing when conditions suits? If so, what is it called?

Answer 7

Yes - called dimorphic fungi

Question 8

What % of fungal species are yeast?

Answer 8

<1% but include several highly medically relevant ones

Question 9

What is the aim of anti microbial drug therapy?

Answer 9

to achieve inhibitory levels of agent at the site of infection without host cell toxicity

Question 10

How is selective toxicity relevant to treating fungal disease?

Answer 10

Anti microbial drug therapy relies upon identifying molecules with selective toxicity for organism targets—> this means exploiting the differences between fungi and human cells in order to treat the fungi rather than damaging our cells

Question 11

Slides 8+9

Question 12

What factors of fungi makes it particularly difficult to treat compared to bacteria?

Answer 12

The fact that fungi are eukaryotic

Question 13

In what population can severe disease be caused by a small number of fungi

Answer 13

Immunocompromised

Question 14

What is mucosal candidiasis

Answer 14

Mucosal surfaces affected by growth of candida

Question 15

How is mucosal candidiasis treated?

Answer 15

Topical or oral azoles

Question 16

What is invasive candidiasis mostly likely due to?

Answer 16

Invasive candidiasis is mostly due to infection of prosthetic devices or intra-abdominal disease

Question 17

What does cryptococcus cause and in what population?

Answer 17

Cryptococcus causes acute or chronic meningitis in patients with reduced cell mediated immunity

Question 18

What are the infectious and non-infectious differential diagnoses of acute/chronic meningitis?

Answer 18

Infective -

Tuberculosis
Cryptococcus
Dimorphic fungi – Histoplasma, Coccidioides, Blastomyces
Lyme
Brucella
Syphilis

Non-infective -

Sarcoidosis
Behçets’s
SLE
Malignant
Drug induced

Question 19

What is invasive aspergillosis normally associated with what populations?

Answer 19

Invasive aspergillosis is normally associated with profound immunocompromise but is increasingly recognised in patients with severe viral infection

Question 20

What does pneumocystis jirovecii cause and in what population?

Answer 20

Pneumocystis jirovecii causes a pneumonitis with severe hypoxia in the immunocompromised