Fungi

Question 1

Fungi Classifications (4)

Answer 1

• Zygomycetes
• Ascomycetes
• Basidiomycetes
• Fungi Imperfecti

Question 2

Zygomycetes

Answer 2

forms sporangium where many nuclei undergo meiosis (ballsack, z=biggest)

Question 3

Ascomycetes

Answer 3

forms ascus (4-8 spores in sac- long narrow dick)

Question 4

Basidiomycetes

Answer 4

spores (conidia) bud from basidium- club-shaped terminal cell (baseball bat)

Question 5

Distinguishing fungi by color (2)

Answer 5

Dermaticious (color) vs. hyaline (colorless)

Question 6

Growth forms (8)

Answer 6

• Yeast
• Mold
• pseudohyphae
• Clamydospores
• Conidia
• Macroconidia
• Arthroconidia
• Phiaoloconidia

Question 7

Yeast

Answer 7

Smooth, creamy round in culture (ex candida)

Question 8

Mold

Answer 8

Filaments/hyphae, form mycelium, (ex aspergillus)

-form fuzzy,colored colonies

Question 9

Pseudohyphae

Answer 9

fungi growth form where yeast buds elongate but dont separate- looks similar to hyphae but individual cells

Question 10

Chlamydospores

Answer 10

Large round terminal cells with thick walls

Question 11

Conidia

Answer 11

Thick walled dispersion stage, microconidia are tiny ones

Question 12

Macroconidia

Answer 12

Giant conidia, septa walls divide

Question 13

Arthroconidia

Answer 13

Form chain of cells, every other has thick septa dividing, later break along these joints

Question 14

Phiaoloconidia

Answer 14

Dominatrix Randy Trident- conidia chains bud from terminal cells

Question 15

Types of fungal infections

Answer 15

superficial, cutaneous, subcutaneous, systemic

-primary vs. opportunists

Question 16

Piedra

Answer 16

Superficial fungal infection of hair

Question 17

Tinea (disease, hallmark, exs)

Answer 17

superficial infection of skin

• see lesion with inflamed ring, cleared center
• exs: trichophyton, epidermophyton, microsporum
• distinguish by micro/macroconidia, but usually dont ID (just give drug and kill)

Question 18

Tinea Corporis

Answer 18

ringworm (tinea on body surface, mainly arms/legs)

Question 19

Tinea Capitis (disease, hallmark)

Answer 19

Tinea of head

-Use fluorescent Wood’s Lamp to ID

Question 20

Tinea barbae

Answer 20

Tinea of face

Question 21

Tinea pedis

Answer 21

Athlete’s foot

Question 22

Tinea unguim

Answer 22

aka onychomycosis (fingernail infection)

Question 23

Subcutaneous mycoses

Answer 23

Usually infected by trauma, fungi enter. Form abcess, or mycotoma (fungus tumor)

Question 24

Sporothrix Schenkii (disease, common infection, appearance)

Answer 24

• cause of subcutaneous mycosis
• found in soil, common infection among gardeners, stick with wood
• elongated yeast
• looks similar to actinomycetes (bacteria) so need distinguish before treatment

Question 25

Systemic mycoses (hallmark, mode of infection, human/human transmission?, form)

Answer 25

endemic to specific area, infect healthy people - usually respiratory infection first - occupational hazard - little human/human transmission - Dimorphic (yeast at 37º in infection, hyphae in culture at 30º)

Question 26

Blastomyces Dermatitis (infection type, form, geography)

Answer 26

Systemic mycosis - visualize with KOH - broad-based buds (BBB for BD) - found east of mississippi in river banks, beaver dams

Question 27

Histoplasma Capsulatum (culture/tissue appearances, geography, infection)

Answer 27

- systemic mycoses - "Black sun" appearance in culture, tiny intracellular yeast in infection(often of macrophages) - Ohio/Mississippi river valleys, bird/bat guano soil

Question 28

Coccidioides immitis (geography, form in culture/tissue)

Answer 28

Southwest US desert soil | -large spherule in lung, arthroconidia in culture

Question 29

Paracoccidiodes Braziliensis (form, geography)

Answer 29

"ships wheel"- yeast with buds | -found in central/south america

Question 30

Candida Albicans (form, infection location, infections)

Answer 30

- tons of morphologies - normal flora of mucous membranes (skin, GI, vagina) - can cause vaginal infections (no colored discharge like trachomatosis), GI/skin infections in infants, thrush in adults - kind of opportunist, so thrush can be sign of immune deficiency

Question 31

Cryptococcus neoformans (form, special stain, infection)

Answer 31

Heavily encapsulated yeast, visualize with india ink -infects brain/meninges (so commonly confused with s. pneumoniae, h. influenzae, n. meningitides)

Question 32

Opportunistic Pathogens (4)

Answer 32

- Aspergillus - Zygomycetes (mucor + rhizopus) - pneumocystis jirovecii - Candida kind of

Question 33

Aspergillus (infection demographic, body area, form)

Answer 33

- Opportunistic fungus common in neutropenic patients - lung infection, can spread to heart/vessels - form hyphae in tissue

Question 34

Mucor + Rhizopus (infection, location)

Answer 34

Opportunistic fungi that infect nasopharynx, can spread to brain

Question 35

Pneumocystis Jirovecii (infection, patient demographic)

Answer 35

Opportunistic fungi | -Rare cause of disease- common in AIDS patients