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Flashcards in Skin- Fungus Deck (51):
1

What is tinea capitis

Infection of scalp eye brows, lashes Hair breaks off scalp (ectothrix) Formation of spores on hair (endothrix)

1

Tinea pedis characteristics

Athletes foot Agents: T mentagrophytes, T. rubrum, E. floccosum

2

Tinea barbae

Infection of beard Usually zoophilic T. verrucosum: cattle T. Mentagrophytes: mice, rodents

2

Tinea unguium

Nail infection by dermatophyte Trichophyton rubrum T. Mentagrophytes E. Floccosum

3

Only pathogenic species of epidermophyton

E. Floccosum

3

What is the cause of ringworm in skin

T. Tonsurans

3

Tx for sporotrichosis

Oral potassium iodide

4

Mycobacterium Ulcerans (buruli ulcer) vs Mycobacterium marinum

Slow growing Not pigmented Same presentation as Mycobacterium marinum

5

What kind of staining is needed for trichosporon

PAS

5

Cause of black piedra

Piedraia spp

6

Microsopic examination of hair

Collect misshapen, broken hair from scalp Treat with KOH

7

Detect mycobacteria marinum

Acid fast Yellow pigment in light requires 28-30 degrees C

8

Treatment of nail infections

longterm oral systemic antifungal

8

Fungal infections of external otitis

Aspergillus species

9

What other infections found with malassezia furfur

Venous catheters Seborrheic dermatitis Dandruff

9

Endothrix ringworm of scalp

T tonsurans

10

Characteristics of E. Floccosum spores

Macroconidia Smooth walled large

11

Presentation of white piedra

Asymptomatic growth on hair shaft White nodules easily pulled off Warm moist conditions predispose

13

Tinea nigra characteristics

Superficial skin infection (stratum corneum) Brow to black lesions on skin (palm/soles)

14

How to examine fungi (general)

PAS stain (gives fuchsin color) Silver stain (black) non fungal will be blue green Sabouraud agar for fungi

16

Microsporum characteristics

Attacks skin and hair, not nails

17

What are hyalohyphomycosis

Non black mold fungal infections Infections caused by non melanized septate, filamentous,

17

Chromoblastomycosis characteristics

Called verrucous dermatitis From soil Gives wart like nodules Painless NO spread of infection

18

Phaeohyphomycosis

Black mold have melanin containing filamentous hyphae Cutaneous/subcutaneous leseion

19

What is Eumycetoma

Madura foot Infection from trauma to feet, lower extremities, hands

20

What is tinea cruris

Jock itch T. rubrum/ e. Floccosum Usually bilateral

20

Mycobacterium Chelonae characteristics

Acid fast Difficult to treat

21

Control of white piedra

Shaving, application of antifungal agents

23

Ectothrix ringworm of scalp

M. Audouinii M Canis M gypseum

25

Trichophyton Characteristics

Attacks skin, hair, nails Life long nail infections Macroconidia smooth walled pencil shaped

26

Microscopic examination of superficial fungal infections of skin

Take scales from advancing border of lesion

27

Characteristics of Mycobacterium marinum disease

Cuts from working around sea water causes infection Chronic non healing lesions to hands, feet

29

What causes white piedra (superficial infection)

Trichosporon

31

Characteristics of Pityriasis versicolor

Superficail chronic rash Fine scaling of upper trunk and shoulders

32

Typical presentation of someone with sporotrichosis

Working in garden got pricks from thorns on rose, swelling on skin

34

What do you grow Trichophyton rubrum plate

Potato dextrose agar (red color)

35

What are sources of fungal infections

Anthropophilic (humans) Zoophilic (animals) Geophilic (soil)

36

UV examination (wood's light) of fungi

Tinea versicolor- gold

Tinea capitis by microsporum canis and microsporum audouinii- Bright green

Tinea capitis by trichophyton- no fluorescence

37

What is the most common fungal agent in the USA

Pseudoallescheria boydii (petriellidium boydii)

38

What is the presentation of eumycetoma

Swelling leading to abcess formation and then granulomas

40

Black piedra characteristics

Found on shaft of hair typically those in tropics Nodules can not be pulled off

41

What is tinea corporis

Ringworm of upper parts of covered body Most serious chronic infection due to T rubrum

42

Fungal eye infections

Fusarium

43

Epidermophyton characteristics

Attacks skin and nail Not hair

45

Hortae Werneckii characteristics

Colonies smooth, oily, glistening Aged colonies- velvety Hyphae become darker with age Beach soil

46

Macroconidia characteristics

More numerous Rough walls spiny to warty

47

Tinea nigra cause

Hortae werneckii

48

Diagnosis of pityriasis versicolor

Microscopy for M. furfur (spaghetti and meatballs)

49

What causes pityrisasis versicolor

Malassezia furfur

50

What causes Sporotrichosis

Sporothrix schenckii Found: plants, soil, wood, moss

51

What predisposes people to chronic infections

Diabetes Old age Malignancy