22. Pathogenic Fungi

Question 0

___ ____ cause disease in otherwise healthy individuals, regardless of immune status

Answer 0

True pathogen

Question 1

Modes of transmission of Mycoses

Answer 1

Inhalation, trauma, ingestion, rarely spread person to person

Question 2

____ ___: lack genes for colonizing body tissues, but can take advantage of some weakness in host defense to cause disease, only in immune weakened individuals

Answer 2

Opportunistic fungi

Question 3

Clinical manifestations of Mycoses: ___,___,and___.

Often look like other infections especially with respiratory illness like pneumonia.

Answer 3

Fungal infections
Toxicoses (poisoning)
Allergies

Question 4

Treatment of Mycoses can be difficult to treat because:

Answer 4

• Can resist T Cells in cell mediated immune response

- Fungi are similar to human cells, fungicides

Question 5

Systemic Mycoses: Pathogens

Answer 5

Fungal infections that spread throughout the body

Question 6

Opportunistic Fungi:

Answer 6

Do not typically effect healthy individuals

Growing source of infections in AIDS patients, immune compromised, elderly

Question 7

Typical opportunistic fungi

Answer 7

Pneumocystis 
Candida
Aspergillus
Cryptococcus
Mucor

Question 8

Superficial Mycoses

Answer 8

Can be from environment or person to person

Typically in outer layer of skin, nails, or hair; fungi use keratin as a food source

Question 9

Cutaneous & Subcutaneous Mycoses

Answer 9

Typically from soil saprobes (live on dead organisms) but has to go deeper into living tissues not just surface skin layer

Question 10

Mycotoxins:

Answer 10

Fungal toxins which are low molecular weight metabolites that can harm animals & humans by causing poisoning (toxiosis)

Question 11

Mycotoxioses

Answer 11

Caused by eating toxins but not fungus itself

• aflatoxins
• ergometrine

Question 12

Mycetismus

Answer 12

Mushroom poisoning from fungus - symptoms liver damage, nausea, hallucinations

Question 13

Allergies

Answer 13

Typically type 1 hypersensitivity from inhalation of spores or fungus, occasionally type 3 hypersensitivities from chronic inhalation

Question 14

Systemic Mycoses 4 main pathogens

Answer 14

Histoplasma
Blastomyces
Coccidiodes
Paracoccidioides
(All are dimorphic)

Question 15

Histoplasmosis

Answer 15

-Systemic Mycoses
- most common fungal pathogen
Typically from inhalation of soil with fungus, bat or bird droppings

Question 16

Blastomycosis

Answer 16

Blastomycosis dermatitidis is a fungus that causes pulmonary blastomycosis - lung infection which typically resolves but can spread to cause wart like skin lesions
-can infect spine, bone, tissue

Question 17

Coccidiodomycosis

Answer 17

Coccidiodes immitis - found exclusively in southwestern US & carried in dust

Question 18

Paracoccidiomycosis

Answer 18

Paracoccidioides brasillensis starts as lung infection, nearly always spreads causing chronic inflammatory disease of mucous membranes especially gums, tongue, lips
-steering wheel shape to yeast stage

Question 19

Pneumocystis

Answer 19

Pneumocystis jiroveci - obligate parasitic fungus, little known, rare previous to AIDS epidemic, had protozoan characteristics

• treated with anti protozoan drugs
• diagnosed by chest x-ray, stains of lung fluid or biopsy
• seen in malnourished

Question 20

Candidiasis

Answer 20

Common in 40%-80% of healthy individuals, disease in newborns, elderly, AIDS patients, immune compromised
-vaginal yeast, diaper rash, nail infection, thrush

Question 21

Aspergillosis

Answer 21

From inhalation of spores

Commonly causes allergies

Question 22

Zygomycoses

Answer 22

Caused by infection by mucor

Question 23

Cryptococcosis

Answer 23

Inhalation of spores or aerosols from bird droppings