pulmonary fungal infections (systemic mycoses

Question 1

where does systemic mycoses originate?

Answer 1

from the soil. spores and fungi

Question 2

how do systemic mycoses infect people?

Answer 2

inhalation

Question 3

are systemic mycoses person-to-person transmissible?

Answer 3

no they are not

Question 4

are systemic mycoses dimorphic?

Answer 4

yes they are thermally dimorphic.

Question 5

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

Answer 5

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

Question 6

coccidioides organism

Answer 6

c. immitis

Question 7

coccidioides thermally dimorphic?

Answer 7

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

Question 8

where is coccidioides endemic?

Answer 8

US and latin america

Question 9

what does coccidioides look like in the soil?

Answer 9

has hyphae with alternating arthrospores and empty cells.

Question 10

what is important about the coccidioides arthrospores?

Answer 10

they are carried by the wind and inhaled.

Question 11

what happens when coccidioides arthrospores are inhaled?>

Answer 11

within the lung they change into spherules.

Question 12

what are coccidioides spherules?

Answer 12

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

Question 13

how does coccidioides spread within the body?

Answer 13

by direct extension.

Question 14

what does coccidioides infection eventually lead too>

Answer 14

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

Question 15

what happens if coccidioides infects an immunocompromised person?

Answer 15

disseminated infection will result.

Question 16

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

Answer 16

hematogenously. bone, meninges.

Question 17

how do we diagnose coccidioides

Answer 17

PPD with coccidiodin or spherulin.

Question 18

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

Answer 18

+ means exposed, cleared or contained infection.

- means unexposed or disseminated infection with immunosuppression.

Question 19

how does a contained coccidioides infection present?

Answer 19

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

Question 20

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

Answer 20

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

Question 21

what are desert bumps?

Answer 21

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.

Question 22

what is valley fever?

Answer 22

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

Question 23

what does a disseminated coccidioides infection present?

Answer 23

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

Question 24

what populations are at risk for dissemination?

Answer 24

africans, filipino, late-pregnancies.

Question 25

what is a good sign of disseminated coccidioides infection?

Answer 25

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

Question 26

what labs for coccidioides infection?

Answer 26

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

Question 27

what do we culture coccidioides on?

Answer 27

sabourgauds agar.

Question 28

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

Answer 28

hyphae with arthrospores. careful the cultures are infectious!

Question 29

treatment for mild coccidioides

Answer 29

none.

Question 30

treatment for lung lesions or disseminated coccidioides

Answer 30

amphotericin B or itraconazole.

Question 31

treatment for coccidioides meningitis

Answer 31

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

Question 32

how to prevent coccidioides

Answer 32

immunosuppressed should avoid endemic areas.

Question 33

histoplasmosis organism

Answer 33

H. capsulatum

Question 34

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

Answer 34

yes dimorphic. mold in soil, yeast in tissue.

Question 35

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

Answer 35

tuberculate macroconidia and microconidia

Question 36

features of H. capsulatum tuberculate macroconidia

Answer 36

thick walls, fingerlike projections. grows in culture

Question 37

features of H. capsulatum microconidia

Answer 37

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

Question 38

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

Answer 38

the microconidia

Question 39

where is H. capsulatum endemic?

Answer 39

US river valleys. mississippi, Ohio.

Question 40

where are H. capsulatum microconidia contracted?

Answer 40

from the soil. esp bird droppings, bat guano.

Question 41

what can set off an outbreak of H. capsulatum

Answer 41

construction with contaminated soil

Question 42

how are we infected by H. capsulatum

Answer 42

the spores are inhaled.

Question 43

what happens after the H. capsulatum spores are inhaled

Answer 43

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

Question 44

how does H. capsulatum avoid death within the lysosome?

Answer 44

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

Question 45

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

Answer 45

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

Question 46

high dose exposure of the H. capsulatum

Answer 46

this can cause cavitary lung lesions on the primary infection.

Question 47

what does infection with H. capsulatum and immunosuppression cause?

Answer 47

severe dissemination pancytopenia ULCERATED LESIONS ON THE TONGUE.

Question 48

is PPD useful in H. capsulatum infections?

Answer 48

no. there are too many false results.

Question 49

mild cases of H. capsulatum

Answer 49

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

Question 50

disseminated H. capsulatum can see what?

Answer 50

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

Question 51

what labs for H. capsulatum

Answer 51

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

Question 52

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

Answer 52

oval yeast cells within macrophages.

Question 53

what do we culture H. capsulatum on?

Answer 53

sabourgaurds agar. need to two cultures.

Question 54

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

Answer 54

25: tuberculate macronidia, 37: micronidia yeast.

Question 55

treatment for mild H. capsulatum

Answer 55

none

Question 56

treatment for lung spreading H. capsulatum

Answer 56

oral itraconzole

Question 57

treatment of disseminated H. capsulatum

Answer 57

amphotericin B

Question 58

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

Answer 58

liposomal amphotericin B

Question 59

treatment for meningitis H. capsulatum

Answer 59

fluconazole.

Question 60

why use fluconazole for meningitis?

Answer 60

because it penetrates the CSF well.

Question 61

blastomyces organism.

Answer 61

Blastomyces dermatitidis

Question 62

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

Answer 62

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.

Question 63

where is Blastomyces dermatitidis endemic?

Answer 63

north america in the great lakes region.

Question 64

where does Blastomyces dermatitidis grow?

Answer 64

in the wet, rich soil.

Question 65

how do we contract Blastomyces dermatitidis

Answer 65

by inhalation of the conidia

Question 66

what happens when inhaled

Answer 66

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

Question 67

what does the mild Blastomyces dermatitidis infection look like

Answer 67

nonspecific flulike

Question 68

what does Blastomyces dermatitis pneumonia look like

Answer 68

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

Question 69

Blastomyces dermatitidis chronic illness?

Answer 69

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

Question 70

fast severe form Blastomyces dermatitidis

Answer 70

ARDS with a fever.

Question 71

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

Answer 71

bone and joint involvement with ski lesions.

Question 72

labs for Blastomyces dermatitidis infection

Answer 72

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

Question 73

are PPD and serology useful for Blastomyces dermatitidis

Answer 73

no they are nonspecific.

Question 74

treatment for most Blastomyces dermatitidis

Answer 74

itraconazole

Question 75

treatment for severe Blastomyces dermatitidis

Answer 75

amphotericin B

Question 76

what other treatment is useful for Blastomyces dermatitidis

Answer 76

surgical excision of the loci

Question 77

paracoccidiodes brasiliensis dimorphic?

Answer 77

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

Question 78

where is paracoccidiodes brasiliensis endemic?

Answer 78

latin america

Question 79

how is paracoccidiodes brasiliensis contracted?

Answer 79

inhalation of spores.

Question 80

what happens when paracoccidiodes brasiliensis is inhaled

Answer 80

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.

Question 81

juvenile type of paracoccidiodes brasiliensis

Answer 81

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

Question 82

chronic adult form of paracoccidiodes brasiliensis infection

Answer 82

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

Question 83

labs for paracoccidiodes brasiliensis

Answer 83

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

Question 84

how long to culture paracoccidiodes brasiliensis?

Answer 84

2-4 WEEKS.

Question 85

is skin test useful for paracoccidiodes brasiliensis

Answer 85

no.

Question 86

treatment for paracoccidiodes brasiliensis

Answer 86

itraconazole for 6 mon and needs improvement in general health.

Question 87

what is the infectious source for the mycoses?

Answer 87

environment!

Question 88

what drug reasonably treats most systemic mycoses?

Answer 88

amphotericin B

Question 89

which of these is an intracellular organism?

Answer 89

histoplasma!