Self Study 2

Question 1

what bact causes TB

Answer 1

myobacterium tuberculosis

Question 2

where does myobacterium TB thrive

Answer 2

upper lobe and upper part of lower lobe

Question 3

why does MBTB thrive in certain areas of the lung

Answer 3

they are aerobic bacteria and these areas of the lung have inc o2 content

Question 4

what makes mbtb resistant to destr

Answer 4

outer waxy capsule

Question 5

what does the outer waxy capsule on mbtb allow

Answer 5

to continue prod in dead and calcified lesions

Question 6

what are mbtb capable of

Answer 6

retaining growth

Question 7

how many new tb cases occur a year

Answer 7

8 mill

Question 8

how many people die from tb a year

Answer 8

2 mil

Question 9

how many new cases of tb occured in canada in 2003

Answer 9

1600

Question 10

how many people in canada died from tb in 2003

Answer 10

750

Question 11

who has inc incidence for tb

Answer 11

people living in crowded conditions, foreigners

Question 12

2 forms of tb

Answer 12

m. tuberculosis hominis

m. tuberculosis bovine

Question 13

another name for m. tuberculosis hominis

Answer 13

human tb

Question 14

how is bovine tb acquired

Answer 14

drinking milk from infected cows

Question 15

what part of the body does m. tb bovine affect first

Answer 15

GI tract

Question 16

how does h. tb hominis travel

Answer 16

airborne infc.

Question 17

mechanism of tb m hominis travel

Answer 17

droplets are in air when infected person coughs, sneezes, talks, particles evaporate and are suspended in the air

Question 18

what happens when a tb bacteria is inhaled

Answer 18

travel down bronchial tree and deposit in alveoli

Question 19

what happens to the bacilli once they are deposited in alveoli

Answer 19

alveolar macrophages phacocytose

Question 20

why are bacilli not killed after alveolar macrophages attack them

Answer 20

cell wall blocks the fusion of phagosomes and lysosomes

Question 21

what happens when the fusion of phagosomes and lysosomes is stopped by the bacilli

Answer 21

macrophages initiate cell mediated immune response

Question 22

how are bacilli antigens presented to t lymphocyte

Answer 22

macrophages which have ingested them present them

Question 23

why is lung tissue damaged in TB

Answer 23

lytic enzymes are released by t macrophages

Question 24

why do t macrophages release lytic enzymes

Answer 24

sensitized t lymphocytes stimulate macrophages to produce lytic enzyme

Question 25

Ghon focus

Answer 25

granulomatus legion

Question 26

how do ghon focus' develope

Answer 26

increased cell mediated immune response

Question 27

what does a ghon focus contain

Answer 27

tubercle bacilli, modified macrophages, other immune cells

Question 28

what causes tissue necrosis

Answer 28

when the number of organisms is high, H rxn lt necrosis

Question 29

what lymph nodes do tb bacteria travel down via lympth channels and end up

Answer 29

tracheobronchial lymph nodes

Question 30

what happens when tb bacteria is in tracheobronchial lymph nodes

Answer 30

cheese like granulations form

Question 31

ghon complex

Answer 31

combination of primary lung lesions and lymph node granulomas

Question 32

what happens to a ghon complex over time

Answer 32

heals, but dormant bact may remain

Question 33

what happens if somebody with dormant TB becomes immunocompromised later on

Answer 33

dormant infc can dev into secondary tb

Question 34

primary tb

Answer 34

infc that develops in previously unexposed persons

Question 35

what happens when people with intact immune systems develop a primary infc

Answer 35

supressed infc

Question 36

why is the infc in primary tb supressed

Answer 36

t lymphocytes and macrophages surround organisms and limit spread

Question 37

do people with tb have an active disease

Answer 37

no

Question 38

what happens in primary tb when a pt has compromimsed IR

Answer 38

they dev progressive primary tb with destruction of lung tissue that spreads to multiple sites within the lung

Question 39

miliary tb

Answer 39

rare form of tb that moves into blood vessel causing lesions

Question 40

secondary tb

Answer 40

occurs when pt has laready been exposed to disease

Question 41

what causes secondary tb

Answer 41

reinfection from another inhaled droplet or reactivation of a healed primary lesion

Question 42

what is an aggravating factor for secondary tb

Answer 42

cell mediated H rxn that causes cavities to merge and create one large cavity

Question 43

what can merging of cavities cause

Answer 43

plueral effusion | tb emphysema

Question 44

mnfts primary tb

Answer 44

``` non spec and insidious fever wt loss fatigue night sweats ```

Question 45

what other mnfts may accompany primary tb

Answer 45

pleuritis | lymphadenitis

Question 46

mnfts of secondary tb

Answer 46

``` low grade fevers night sweats fatigue anorexia wt loss dry cough ```

Question 47

what does disease process of secondary tb do to a dry cough

Answer 47

turns it into a productive cough with purulent or blood tinged sputum

Question 48

what mnfts occur in later secondary tb

Answer 48

dyspnea | orthopnea

Question 49

dx for tb

Answer 49

tuberculin skin tests cxr culture

Question 50

what does it mean if a person tests positive for skin tb

Answer 50

they may not have an active form, they have been exposed to baccillus and cell mediated immunity forms

Question 51

what do cxr's show in pts with tb

Answer 51

``` consolodated lesions (active) lesions, scars (inactive) ```

Question 52

goal of tx for tb

Answer 52

eradicating bacteria while not creating drug resistance in pt

Question 53

types of tx for tb

Answer 53

chemo | antimycobacterial tx

Question 54

what drug is used to treat tb in pts >35yo, immunocompromise, peds,

Answer 54

isoniazid

Question 55

what drugs are usually used in tb

Answer 55

``` INH rifampin pyrazinamide ethambutol streptomycin ```

Question 56

how do we avoid drug resistance

Answer 56

use combinations of drugs

Question 57

what vaccine is used in pts who have high risk of dev infc

Answer 57

calmette geurin

Question 58

what does calmette geurin do in skin tests

Answer 58

changes ability to detect dormant tb,

Question 59

where does the calmette geurin vaccine inconsistent

Answer 59

pulmonary tb