Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MYCOVIRO > 6.1-SUBCUTANEOUS OVERIEW + SPOROTRICHOSIS > Flashcards

6.1-SUBCUTANEOUS OVERIEW + SPOROTRICHOSIS Flashcards

1
Q

 Infects deeper tissues like dermis and disseminating into parts of the body like lymphatic

A

SUBCUTANEOUS MYCOSES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

SUBCUTANEOUS MYCOSES
Most of the fungi causing these diseases are

A

dematiaceous or phaeiod. Some are hyaline or moniliaceous.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

All fungi under these diseases are dematiaceous (pigmented) that cause subcutaneous mycoses

A

Sporotrichosis
Chromoblastomycosis
Phaeohyphomycosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Mycetoma - mostly dematiaceous fungi (pigmented) except

A

Pseudallescheria boydii and Acremonium falciforme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

 Fungi that cause subcutaneous mycoses normally reside in soil or on vegetation

They are found in soil and vegetation, which is why agricultural workers, especially males, are usually infected.

A

SUBCUTANEOUS MYCOSES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

SUBCUTANEOUS MYCOSES  The fungi causing these infections are ________________in nature

A

saprophytic and ubiquitous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

SUBCUTANEOUS MYCOSES MOT:

A

traumatic inoculation to skin or subcutaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

General continuation of lesions from subcutaneous mycosis infections

A

become granulomatous and
expand slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

are localized collections of immune cells (like macrophages) that form in response to chronic inflammation or infection

A

granulomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Subcutaneous mycosis can become systemic?

A

Yes in rare cases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

 Species belong to Sporothrix spp. complex

A

o Sporothrix schenckii
o Sporothrix mexicana
o Sporothrix globosa
o Sporothrix luriei
o Sporothrix albicans
o Sporothrix inflata
o Sporothrix brasiliensis

Sexy mexicanas across the globe lure albinos to inflate them in brasil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

SPOROTRICHOSIS AKA

A

Rose Gardener’s Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the most common form of sporotrichosis

A

Lymphocutaneous sporotrichosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

o A thermally dimorphic fungus that lives on vegetation
 The fungi is capable of having both the yeast and mold form

A

Sporothrix schenckii complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

SEGWAY

 C.immitis
 in some references they say that
it is not dimorphic. WHY?

A

C.immitis produce spherules
with spores found in the tissue INSTEAD OF YEASTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

other systemic mycoses but hindi included sa lecture since the systemic mycosis it causes ay sa mga immunocompromised patients

Systemic dimorphic fungi that only infect immunocompromised patients

A

Taloromyces marneffei (previously
known as Penicillium marneffei)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

 S. schenckii grows well on routine agar media, and at RT ○

 Colonial appearance:
o Young colonies

A

are small, moist, and white to
cream colored

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

 S. schenckii grows well on routine agar media, and at RT ○

 Colonial appearance:
Older colonies become

A

membranous, wrinkled and fuzzy with age and coarsely matted; dark brown to black with leathery consistency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What type of agar media does Sporothrix schenckii grow well on?

A

Routine agar media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens to the yeast phase of S. schenckii on antibiotic media?

A

It is inhibited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Can S. schenckii grow in the presence of cycloheximide?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How does S. schenckii appear on Brain Heart Infusion Agar (BHIA) at 37°C?

A

Soft, white, cream to tan-colored

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is BHIA used for in diagnosing S. schenckii infections?

A

It is a biphasic medium used to demonstrate dimorphism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is dimorphism confirmed in S. schenckii?

A

By converting mycelial form to yeast form on BHIA or BHI-blood agar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What conditions promote S. schenckii dimorphism in BHI-blood agar?

A

Addition of red cells, 5% CO₂, incubation at 35-37°C for 1-5 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the microscopic appearance of the mycelial form of S. schenckii?

A

Narrow, septate hyphae with pyriform conidia arranged singly or in clusters (flowerette arrangement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What type of conidia may be produced in older S. schenckii cultures?

A

Single-celled, thick-walled, black-pigmented conidia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the microscopic appearance of the yeast form of S. schenckii?

A

Small, elliptoid budding, cigar-shaped (fusiform) yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How long does it take to convert S. schenckii from mold to yeast form?

A

1 to 5 days using a medium with blood and 5% CO₂

30
Q

What is the antigenic component of S. schenckii used in skin testing?

A

Sporotrichin

31
Q

What reaction does Sporotrichin elicit in infected individuals?

A

Positive delayed skin reaction

32
Q

How is Sporotrichin prepared?

A

From heat-killed saline suspensions or carbohydrate fractions

33
Q

Why do some normal individuals test positive for Sporotrichin?

A

Due to specific or cross-reactive antibodies

34
Q

What is a limitation of the Sporotrichin skin test?

A

False-positive results may occur

35
Q

How is S. schenckii introduced into the body?

A

Through trauma, introducing conidia or hyphal fragments into the skin

36
Q

What is the most common form of sporotrichosis?

A

Lymphocutaneous sporotrichosis

37
Q

How does lymphocutaneous sporotrichosis progress?

A

Initial lesion appears on extremities

Nodular and ulcerative lesions develop along lymph channels

Thickening of draining lymphatics

Multiple subcutaneous nodules and abscesses

38
Q

What are the less common forms of sporotrichosis?

A

Fixed cutaneous and mucocutaneous sporotrichosis

39
Q

Presence of eosinophilic material (up to 10 μm thick) radiating around yeast cells (asteroid bodies)

A

Splendore-Hoeppli phenomenon

40
Q

What color does eosinophilic material appear under the microscope?

41
Q

What stain is most commonly used for S. schenckii in histopathology?

A

H&E (hematoxylin and eosin)

42
Q

What are the differential diagnoses for sporotrichosis skin lesions?

A

Mycobacterium marinum (swimming granuloma) and cutaneous leishmaniasis

43
Q

How does fixed cutaneous sporotrichosis present?

A

Single, non-lymphangitic nodule

Confined to inoculation site

Common in endemic areas like Mexico

Limited progression, but potential for dissemination

44
Q

How does primary pulmonary sporotrichosis occur?

A

Inhalation of S. schenckii conidia

45
Q

What condition does pulmonary sporotrichosis mimic?

A

Chronic cavitary tuberculosis

46
Q

How can tuberculosis be ruled out in suspected pulmonary sporotrichosis cases?

A

Direct Sputum Smear Microscopy (DSSM) for acid-fast bacilli

47
Q

Which patients are at higher risk for sporotrichosis dissemination?

A

Those with impaired cell-mediated immunity

48
Q

What specimens are used to diagnose Sporothrix schenckii infection?

A

Biopsy material or exudate from granulomatous or ulcerative lesions

49
Q

How is Sporothrix schenckii confirmed in culture?

A

By demonstrating dimorphism using BHIA with red cells

50
Q

What is the characteristic microscopic appearance of Sporothrix schenckii?

A

Small, cigar-shaped yeast

51
Q

Why is Sporothrix schenckii rarely found in KOH or calcofluor white stain?

A

Yeasts are not abundant in direct smears

52
Q

Which stains enhance sensitivity in histopathologic sections for fungal cell walls?

A

Gomori methenamine silver (GMS) and periodic acid-Schiff (PAS)

53
Q

What colors do fungal elements appear in GMS and PAS stains?

A

GMS = Black
PAS = Magenta

54
Q

What is the advantage of fluorescent antibody staining in diagnosing Sporothrix schenckii?

A

It allows direct identification of fungal elements

55
Q

How does Sporothrix schenckii appear in hematoxylin and eosin (H&E) stain?

A

As an asteroid body with a central basophilic yeast cell and radiating eosinophilic extensions

56
Q

Are GMS and PAS stains specific to Sporothrix schenckii?

57
Q

What histopathologic finding is more specific for sporotrichosis?

A

Asteroid bodies

58
Q

What is the most reliable method for diagnosing Sporothrix schenckii?

59
Q

What culture media are used for isolating Sporothrix schenckii?

A

Sabouraud’s agar with antibacterial antibiotics

60
Q

At what temperature should Sporothrix schenckii cultures be incubated?

A

25–30°C

61
Q

How is Sporothrix schenckii confirmed in culture?

A

By demonstrating growth at 35°C and conversion to the yeast form

62
Q

What serologic test is used to detect antibodies to Sporothrix schenckii?

A

Agglutination test using yeast cell suspensions or antigen-coated latex particles

63
Q

Why is serologic testing for Sporothrix schenckii not always useful?

A

High titers do not develop early in the disease
False positives can occur in previously exposed but uninfected patients

64
Q

What is the principle of serologic testing for sporotrichosis?

A

Detection of antibodies using reagent antigen from Sporothrix schenckii

65
Q

Is Sporothrix schenckii infection always treated?

A

No, some cases are self-limited

66
Q

What is the treatment of choice for sporotrichosis?

A

Oral Itraconazole or another azole antifungal

67
Q

What alternative treatment is effective for sporotrichosis?

A

Oral saturated solution of potassium iodide (in milk)

68
Q

What antifungal is used for systemic Sporothrix schenckii infections?

A

Amphotericin B

69
Q

Where is Sporothrix schenckii commonly found in nature?

A

Sphagnum moss
Rose thorns
Decaying wood
Pine straw
Prairie grass
Other vegetation

70
Q

What percentage of sporotrichosis cases occur in males?

71
Q

Which occupations are at higher risk for sporotrichosis?

A

Agricultural workers
Forest rangers
Horticulturists
Other similar occupations

72
Q

How can sporotrichosis be prevented?

A

Minimizing accidental inoculation
Using fungicides

MYCOVIRO (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions