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Flashcards in FA Mycobacteria Deck (31):
1

PPD + means

current infection, past exposure, or BCG vaccinated

2

PPD - means

no infection or anergic (steroids, malnutrition, immunocompromise) and in sarcoidosis

3

What is a more specific test (have fewer false positives from BCG vaccine) than PPD for TB?

Interferon-gamma release assay (IGRA)

4

histology of TB

Caseating granuloma - central necrosis with multinucleate Langerhans giant cell

5

Infection with TB in a non immune host (usually child) -->

primary tuberculosis

6

primary TB is characterized by

Ghon complex = hilar nodes + Ghon focus (usually in mid zone of lung)

7

If primary TB heals by fibrosis -->

immunity and hypersensitivity --> Tuberculin +

8

If primary TB --> prorgressive lung disease (usu in HIV or malnutrition) -->

death (rare)

9

if primary TB --> military TB -->

death

10

if primary TB --> re allergic lymphatic or hematagenous dissemination -->

dominant tubercle bacille in several organs --> reactivation in adult live

11

Infection with TB in a partially immune hyper sensitized host (usually adult) -->

secondary TB (reinfection)

12

secondary TB presents as a

fibrocaseous cavitary lesion usually in upper lobes

13

what are the six places where extra pulmonary TB tends to present?

CNS (parenchymal TB or meningitis)
Vertebral body (Pott dz)
Lymphadenitis
Renal
GI
Adrenals

14

What are the four big TB symptoms

1. Fever
2. Night sweats
3. Weight loss
4. Hemoptysis

15

What disease causes pulmonary TB like symptoms?

M Kansasii

16

What disease causes disseminated non-TB disease in AIDS and is often resistant to multiple drugs?

M avium-intracellulare

17

What is the treatment for M avium-intracellulare?

prophylactic treatment with azisthromycin

18

what virulence factor in mycobacteria inhibits macrophage maturation and induces release of TNF-apha?

cord factor

19

what does cord factor of TB do?

inhibits macrophage maturation and induces release of TNF-alpha

20

What part of mycobacteria inhibits phagolysosomal fusion?

Sulfatides (surface glycolipids)

21

What do sulfatides in TB do?

inhibit phagolysosomal fusion

22

An acid-fast bacillus that likes cool temperatures (infects skin and superficial nerves -->
"glove and stocking" loss of sensation) and cannot be grown in vitro

Mycobacterium leprae

23

What is the leprosy reservoir in the US?

Armadillos

24

What are the two forms of leprosy/Hansen?

1. Lepromatous
2. Tuberculoid

25

Presents diffusely over the skin with leonine facies and is communicable; characterized by low cell-mediated immunity with a humoral Th2 response

Lepromatous Hansen

26

limited to a few hypoesthetic, hairless skin plaques; characterized by high -cell mediated immunity with a largely Th1-type immune response

Tuberculoid Hansen

27

Immune response to lepromatous hansen?

low cell-mediated immunity with a humoral Th2 response

28

immune response to tuberculoid hansen?

high -cell mediated immunity with a largely Th1-type immune response

29

treatment for tuberculoid form of hansen?

multi drug therapy of damson and rifampin for 6 months

30

treatment for lepromatous form of hansen>

dapsone + rifampin + clofazimine for 2-5 years

31

describe the leonine facies of leprosy

loss of eyebrows, nasal collapse, lumpy earlobe