Fungi

Question 1

Draw a basic fungal cell

Answer 1

Question 2

How do fungi replicate

Answer 2

either asexual or sexual ( most do both )
Most produce spores -impt in infection

Question 3

Draw the replication cycles of a fungi

Answer 3

Question 4

Name 3 phases of sexual cycle of fungi and what happens

Answer 4

Plasmogamy phase- fusion cytoplasm ( not nuclei ) of 2 parent cells

Karyogamy phase -haploid nuclei fuse to form diploid nucleus ( zygote )

Meiosis phase - zygote splits into 2 daughter cells - then spores form and germinate and hyphae form and repeats

Question 5

Name 4 ways to prevent fungal infections

Answer 5

1. Physical barriers
2. saliva flushing
3. Innate responses -antifungal peptides /complement
4. Microbial competition
5. Host specific - IgA stop adherence of candid
   - macrophage phagocytosis

Question 6

Treatment of oral candida

Answer 6

1.Good oral hygiene - brushing teeth /dentures
Disinfecting dentures
2.Diet advice - decrease Carbohydrate intake
3. Health/systemic advice- stop smoking/stop drugs /nutritional
4. Antifungal medications

Question 7

Name two classes antifungals and explain how/where work

Answer 7

“azoles” ( fluconazole tablets /miconazole gel) - stop synthesis of ergosterol in fungi which is important in cell membrane integrity - so fragile and breaks/dies

Polyenes ( amphotercin B /nystatin cream )- interact with ergosterol in the membrane so channels form and membrane becomes leaky - resistance rare to these but patient compliance poor

Question 8

3 reasons oral candida reoccur in some patients

Answer 8

did not kill ALL cells
patient immunocompromised
Another endogenous source present so reinfects

Question 9

Name 3 types fungal infection classes

Answer 9

1. Superficial candidiasis- eg oral mucosa- candida
2. Subcutaneous candidosis- below skin
3. Systemic candidiasis - thru out body-aspergillosis

Question 10

Can fungi be found in normal healthy people oral cavity

Answer 10

Yes in 10-40%

Question 11

What people does candid Albicans become more prominent in

Answer 11

Unwell /immunocompromised

Question 12

Name 4 host factors that increase candida infection and why

Answer 12

Immunocompromised - not able mount immune response ie phagocytosis

Diabetics - increased sugars and acidic environments , and as constant sugar source no competition from bacteria as plentiful “food source ‘for both

Prosthesis like dentures - saliva washing compromised and source maybe on prosthesis

Antibiotic treatment - kills off the competing bacteria

Question 13

Name 2 types oral candidiasis and population seen in

Answer 13

1. Pseudmembraneous - creamy white plaques can brush off and see inflamed red mucosa below (elderly/infants/immunocompromised )
2. Plaque like nodular - irregular white plaques cannot scrape off - must refer /biopsy as risk cancer
3. Erythematous - acute post antibiotics - red painful tongue
   -chronic - denture wearers on roof palate

Question 14

Name 2 mechanisms that increases candidia pathogenicity

Answer 14

Candidalysin toxin -
Dimorphism ability
Adhesins allowing to adhere cell wall of host