Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

micro unit 4 > pulmonary fungal infections (systemic mycoses > Flashcards

pulmonary fungal infections (systemic mycoses Flashcards

1
Q

where does systemic mycoses originate?

A

from the soil. spores and fungi

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

how do systemic mycoses infect people?

A

inhalation

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

are systemic mycoses person-to-person transmissible?

A

no they are not

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

are systemic mycoses dimorphic?

A

yes they are thermally dimorphic.

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

When diagnosing systemic mycoses what is the most common organism in the diff? How do you easily distinguish?

A

tuberculosis. These come from american dirt, not european crowds!

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

coccidioides organism

A

c. immitis

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

coccidioides thermally dimorphic?

A

yes, it is a mold in the soil and spherule in the tissue.

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

where is coccidioides endemic?

A

US and latin america

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

what does coccidioides look like in the soil?

A

has hyphae with alternating arthrospores and empty cells.

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

what is important about the coccidioides arthrospores?

A

they are carried by the wind and inhaled.

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

what happens when coccidioides arthrospores are inhaled?>

A

within the lung they change into spherules.

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

what are coccidioides spherules?

A

thick, doubly refracted wall, filled with endospores. when the wall ruptures the endospores are released and develop into new spherules.

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

how does coccidioides spread within the body?

A

by direct extension.

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

what does coccidioides infection eventually lead too>

A

granuloma. CMI and DHSR. if the CMI is healthy then the granuloma will contain the infection in the lung.

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

what happens if coccidioides infects an immunocompromised person?

A

disseminated infection will result.

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

how does coccidioides spread systemically? and common sites of extension?

A

hematogenously. bone, meninges.

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

how do we diagnose coccidioides

A

PPD with coccidiodin or spherulin.

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

what does a +PPD mean for coccidioides? - PPD?

A

+ means exposed, cleared or contained infection.

- means unexposed or disseminated infection with immunosuppression.

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

how does a contained coccidioides infection present?

A

often asymp. but can be flulike (fever and cough) serology +, + PPD.

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

what percent with coccidioides have CXR findings and what are they?

A

50% will have them. infiltrates, adenopathy, effusions.

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

what are desert bumps?

A

this is erythema nodosum due to coccidioides infection. red tender nodules on the skin usually legs. it is a DHSR to the fungal antigens. immunogenic complications of granulomatous infection.

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

what is valley fever?

A

symptoms of the contained infection. also called desert rheumatism. typically subsides spontaneously.

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

what does a disseminated coccidioides infection present?

A

may affect any organ, but commonly the meninges, bone, and skin. meningitis, osteomyelitis, nodules.

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

what populations are at risk for dissemination?

A

africans, filipino, late-pregnancies.

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

what is a good sign of disseminated coccidioides infection?

A

erythema nodosum. this shows that the immune system hasd been reconstituted and trying to fight the infection.

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

what labs for coccidioides infection?

A

tissue specimen for spherule. serology = titer spikes if disseminating… watch for immune response lacking though.

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

what do we culture coccidioides on?

A

sabourgauds agar.

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

what does coccidioides look like on sabourgaurds agar at 25 C?

A

hyphae with arthrospores. careful the cultures are infectious!

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

treatment for mild coccidioides

A

none.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

treatment for lung lesions or disseminated coccidioides

A

amphotericin B or itraconazole.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

treatment for coccidioides meningitis

A

fluconazole, continue as a long-term suppressive. can add amphotericin B intrathecally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how to prevent coccidioides

A

immunosuppressed should avoid endemic areas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

histoplasmosis organism

A

H. capsulatum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

is H. capsulatum dimorphic? and what does it look like?

A

yes dimorphic. mold in soil, yeast in tissue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are the two types of asexual spores for H. capsulatum

A

tuberculate macroconidia and microconidia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

features of H. capsulatum tuberculate macroconidia

A

thick walls, fingerlike projections. grows in culture

37
Q

features of H. capsulatum microconidia

A

smaller, thin, smooth walled. INFECTIOUS. from the environment

38
Q

which form of the asexual spores are infectious for H. capsulatum

A

the microconidia

39
Q

where is H. capsulatum endemic?

A

US river valleys. mississippi, Ohio.

40
Q

where are H. capsulatum microconidia contracted?

A

from the soil. esp bird droppings, bat guano.

41
Q

what can set off an outbreak of H. capsulatum

A

construction with contaminated soil

42
Q

how are we infected by H. capsulatum

A

the spores are inhaled.

43
Q

what happens after the H. capsulatum spores are inhaled

A

they are engulfed by macros. they inhibit the fusion of the phagosome with the lysosome.

44
Q

how does H. capsulatum avoid death within the lysosome?

A

they secrete ammonia and bicarb that buffer the acidic environment. this inactivates the enzymes that are acid dependent.

45
Q

what happens when there is a healthy CMI infected by H. capsulatum ?

A

they form granuloma that eventually calcify and contain the infection. may also see EN

46
Q

high dose exposure of the H. capsulatum

A

this can cause cavitary lung lesions on the primary infection.

47
Q

what does infection with H. capsulatum and immunosuppression cause?

A

severe dissemination pancytopenia ULCERATED LESIONS ON THE TONGUE.

48
Q

is PPD useful in H. capsulatum infections?

A

no. there are too many false results.

49
Q

mild cases of H. capsulatum

A

nonspecific and flulike. cough, chest pain, hemoptysis. there will also be granulomas in the liver and spleen. may see weight loss in elderly.

50
Q

disseminated H. capsulatum can see what?

A

can see cardiac and CNS changes in addition to the tongue lesions.

51
Q

what labs for H. capsulatum

A

biopsy or bone marrow and blood work for pancytopenia, ELISA for histoplasma polysaccharide antigen. DNA probes for histoplasma RNA. urine antigen is useful.

52
Q

what do we look for on the biopsy for H. capsulatum

A

oval yeast cells within macrophages.

53
Q

what do we culture H. capsulatum on?

A

sabourgaurds agar. need to two cultures.

54
Q

what does H. capsulatum look like at 25C, 37C

A

25: tuberculate macronidia, 37: micronidia yeast.

55
Q

treatment for mild H. capsulatum

A

none

56
Q

treatment for lung spreading H. capsulatum

A

oral itraconzole

57
Q

treatment of disseminated H. capsulatum

A

amphotericin B

58
Q

what do we do specially for the treatment of fungal infections if the patient has kidney disease?

A

liposomal amphotericin B

59
Q

treatment for meningitis H. capsulatum

A

fluconazole.

60
Q

why use fluconazole for meningitis?

A

because it penetrates the CSF well.

61
Q

blastomyces organism.

A

Blastomyces dermatitidis

62
Q

is Blastomyces dermatitidis dimorphic? and what does it look like>

A

yes. mold, has hyphae with small pear shaped conidia which are infectious. yeast, is round with doubly refractive wall and a single broad-based bud.

63
Q

where is Blastomyces dermatitidis endemic?

A

north america in the great lakes region.

64
Q

where does Blastomyces dermatitidis grow?

A

in the wet, rich soil.

65
Q

how do we contract Blastomyces dermatitidis

A

by inhalation of the conidia

66
Q

what happens when inhaled

A

50% are asymp. immunosuppression or preexisting pulmonary disease predisposes to dissemination.

67
Q

what does the mild Blastomyces dermatitidis infection look like

A

nonspecific flulike

68
Q

what does Blastomyces dermatitis pneumonia look like

A

high fever, chills, cough, mucopurulent sputum and pleuritic chest pain.

69
Q

Blastomyces dermatitidis chronic illness?

A

looks like TB with pulmonary symptoms, night sweats, weight loss, hemoptysis.

70
Q

fast severe form Blastomyces dermatitidis

A

ARDS with a fever.

71
Q

what is a common symptom that all the forms of Blastomyces dermatitidis can have?

A

bone and joint involvement with ski lesions.

72
Q

labs for Blastomyces dermatitidis infection

A

biopsy shows thick-walled yeast cells with broad-based buds. culture shows hyphae with small pear-shaped conidia.

73
Q

are PPD and serology useful for Blastomyces dermatitidis

A

no they are nonspecific.

74
Q

treatment for most Blastomyces dermatitidis

A

itraconazole

75
Q

treatment for severe Blastomyces dermatitidis

A

amphotericin B

76
Q

what other treatment is useful for Blastomyces dermatitidis

A

surgical excision of the loci

77
Q

paracoccidiodes brasiliensis dimorphic?

A

yes. mold are thin with separate hyphae. yeast is thick-walled with multiple buds.

78
Q

where is paracoccidiodes brasiliensis endemic?

A

latin america

79
Q

how is paracoccidiodes brasiliensis contracted?

A

inhalation of spores.

80
Q

what happens when paracoccidiodes brasiliensis is inhaled

A

primary lesions in the lung. asym is common. more severe infections will include the oral mucous membrane and lymph node enlargement. dissemination is possible if immunosuppressed for many years.

81
Q

juvenile type of paracoccidiodes brasiliensis

A

peds or immunosuppressed. more severe. skin lesions. fever, malaise, weight loss, LAD and HSM.

82
Q

chronic adult form of paracoccidiodes brasiliensis infection

A

less severe, very long latency period up to 30yrs. pulmonary symptoms, oral lesions, skin lesions, nonspecific immune symptoms.

83
Q

labs for paracoccidiodes brasiliensis

A

pus or tissue samples look for yeast cells with multiple buds. serology (significant titers correspond to active).

84
Q

how long to culture paracoccidiodes brasiliensis?

A

2-4 WEEKS.

85
Q

is skin test useful for paracoccidiodes brasiliensis

A

no.

86
Q

treatment for paracoccidiodes brasiliensis

A

itraconazole for 6 mon and needs improvement in general health.

87
Q

what is the infectious source for the mycoses?

A

environment!

88
Q

what drug reasonably treats most systemic mycoses?

A

amphotericin B

89
Q

which of these is an intracellular organism?

A

histoplasma!

micro unit 4 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions