fungal infections and antifungal chemotherapy

Question 1

name the two cellular forms of fungal growth

Answer 1

yeast cells or blastospores=yeasts
hyphae or mycelium=moulds

Question 2

what are the three different fungal lifestyles

Answer 2

saprophytism-nutrition from dead organic material.
symbiosis-mutualism, nutrition from another organism.
parasitism- nutrition from living organic material

Question 3

what are the different fungal infections you can get

Answer 3

superficial- affect skin, hair, nails, mucosal surfaces.
subcutaneous- affect subcataneous tissues.
systemic- affect deep seated tissues.

Question 4

what are dermatophytes

Answer 4

specialised fungi that exploit keratin. e.g; trichophyton, microsporon, epidermophyton.

Question 5

what can dermatophytes cause.

Answer 5

tinea pedis, tinea unguiuim, fungal nail infection.
tinea capitis known as scalp ringworm.

Question 6

what can candida cause

Answer 6

superficial and systemic infections

Question 7

name some known candida

Answer 7

candida albicans, c. glabrata, c.parapsilosis, c.tropicalis, c.krusei,

Question 8

give an example of subcutaneous fungal infecction

Answer 8

sporotrichosis, caused by sporothrix schenckii. can happen after a traumatic implantation. it is associated with sphagnum moss. the disease can track along the lymph nodes

Question 9

how can systemic fungal infections be diagnosed

Answer 9

by isolation of fungus from blood or tissue biopsy

Question 10

what are the 2 types of systemic infections

Answer 10

opportunistic, and true

Question 11

how is systemic candidosis caused and where is it present

Answer 11

caused by candida sp. a superficial disease. present in the blood as candideamia

Question 12

what are risk factors of systemic candidosis

Answer 12

central venous catheters, IV drug abuse, gut surgery, antibiotics, immune suppression, prematurity.

Question 13

what are the types of aspergillosis

Answer 13

1-severe asthma
2- allergic bronchopulomonary
3-aspergilloma(fungal ball)
4-aspergillus sinusitis
5-chronic pulmonary apsergillosis
6-invasive aspergillosis

Question 14

what is invasive aspergillosis

Answer 14

associated with active tissue and blood vessel invasion. usually in immunocompromised patients.

Question 15

how are immunocompetent aspergillosis diagnosed( ABPA, aspergilloma and CPA)

Answer 15

x-ray, CT, culture of sputum, antibody test

Question 16

how are immunocompromised tested(invasive)

Answer 16

CT of chest, culture of broncho alveolar lavage, antigen test, PCR for DNA, biopsy.

Question 17

what is mucormyosis caused by

Answer 17

moulds called mucor, lichtheimia.
it is a rhino-cerebral, pulmonary disease. in immunocompromised patients of uncontrolled diabetes.

Question 18

what is crytococcosis caused by

Answer 18

yeast crytoccus neoformans. cause pulmonary disease and meningitis.

Question 19

what is histoplasmosis caused by

Answer 19

histoplasma capsulatum.
it is dimorphic fungus. pulmonary infection can spread,

Question 19

what are the main classes of antifungal agents

Answer 19

pyrimidine (DNA protein synthesis), polyenes(plasma membrane ergosterol), allylamine(ergosterol biosynthesis), azoles(ergosterol bio), echinocandins( beta 1-3 glucan synthesis), fungerps( beta 1-3 glucan synthesis).

Question 20

name some factors affecting treatment of fungal infection

Answer 20

sensitivity to antifungal, penetration of the antifungal, host response.

Question 20

what is in vitro resistance

Answer 20

failure of fungus to be inhibited

Question 21

what is clinical resistance

Answer 21

failure of patient to respond