TB

Question 1

fatality and Tb from _____

Answer 1

HIV

Question 2

organism causing TB

Answer 2

Mycobacterium tuberculosis

acid-fast aerobic rod

Question 3

transmission

Answer 3

inhalation of aerosolized infectious droplets

Question 4

initial pathophys

Answer 4

1. bacilli grow in lungs
2. vigorous immune response
3. droplet nuclei deposited in lung airspaces
4. alveolar macrophages engulf bacilli

Question 5

types of TB

Answer 5

1. Primary TB
2. Progressive primary tuberculosis
3. Latent TB
4. Reactive TB

Question 6

primary TB

Answer 6

growth occurs, kills macrophages and releases bacilli

local infection and destruction

Unable to be walled off, active form of Dz

Question 7

progressive primary tuberculosis

Answer 7

hematogenous and lymphatic spread of infection

targets: lymph nodes, vertebrae, adrenal gland, meninges, GI tract

OXYGEN rich areas

Question 8

latent TB

Answer 8

lung collects and encaseates within granulomas

lies dormant in lungs (can’t get rid of it!)

NOT infectious, NO active infection

Question 9

reactive TB

Answer 9

disruption of cellular immune function that cause break down of granuloma and development of TB years to months following exposure

Question 10

when is risk of development of reactive TB

Answer 10

<2 yrs following exposure

young and old increased risk

impaired immune action

Question 11

populations in US at risk for TB

Answer 11

immigrants

low SES

homeless

crowded conditions

Question 12

lesions of TB

Answer 12

granuloma with central caseation necrosis

has low levels of O2, low pH, high levels of fatty acids to inhibit growth

Question 13

symptoms of active TB

Answer 13

insidious

cough, weight loss, fatigue, fever, night sweats, hemoptysis

Question 14

extrapulmonary TB

Answer 14

involvement of sites with high O2 tension

mediastinal, retroperitoneal, cervical/scrofula lymph nodes, vertebrae, adrenal glands, meninges and GI tract

Question 15

TB exposure

Answer 15

purified TB injected into skin and strong cell mediated immune response will occur if exposed again

delayed type hypersensitivity response then read again in 47-72 hrs

Question 16

PPD results high risk

Answer 16

5 mm or greater

close contacts, immunosuppressed, clinical or radiographic evidence of TB

Question 17

PPD results low-intermediate risk

Answer 17

10 mm +

persons born in high TB incidence, occupational exposure

Question 18

PPD results unlikely risk

Answer 18

15 mm +

Question 19

qunatiferon test

Answer 19

T cells from those infected with TB release measurable amounts of interferon gamma when mixed with Ags of TB

screen for latent AND active TB

Question 20

evaluation for Active TB infection

Answer 20

PA and lateral CXR

if abnormal - contrast CT of chest

Question 21

if TB is suggestive after imaging…

Answer 21

sputum smear, sputum culture, nucleic acid testing of sputum

Question 22

sputum smear for TB

Answer 22

suggestive but not diagnostic

may take long time for results

Question 23

nucleic acid testing

Answer 23

rapidly diagnostic and can guid treatment

Question 24

lymph node biopsy

Answer 24

preformed if lymphadenopathy present

determine second disorder present or due to TB

Question 25

typical TB CXR

Answer 25

apical cavitary disease, nodules, infiltrates

Question 26

miliary TB

Answer 26

hematologic or lymphatic spread widespread small nodular densities

Question 27

tx of active TB

Answer 27

hospitalization negative pressure ventilation and air exhausted to outside/filtered report of confirmed AND suspected cases to CDC 4 drug regimen

Question 28

labs done for active TB tx

Answer 28

``` baseline CBC renal function LFTs pregnancy HIV status ```

Question 29

4 drug regimen

Answer 29

isoniazid rifampin pyrazinamide ethambutol/streptomycin

Question 30

isoniazid toxicity

Answer 30

peripheral neuropathy increased transaminases weakness

Question 31

Rifampin toxicity

Answer 31

increased transaminases pancreatitis fever, rash, N/V/D

Question 32

pyrazinamide toxicity

Answer 32

increased transaminases, NV

Question 33

ethambutol toxicity

Answer 33

optic neuritis (decreased visual acuity) color blindness

Question 34

how often are sputum spheres collected?

Answer 34

weekly during tx isolation until 3 consecutive negative smears

Question 35

tx concomitant HIV

Answer 35

longer duration of rx some drug interactions with HAART

Question 36

tx of extrapulmonary TB

Answer 36

longer duration of rx consider surgical debridement of bone and corticosteroid

Question 37

tx of TB in pregnancy

Answer 37

teratogen risk of meds breast feeing OK

Question 38

MDR TB

Answer 38

associated with high mortality and short survival prolonged (2-3 yrs) survival

Question 39

how do you tx latent TB?

Answer 39

3-9 mo tx of anti TB meds have to rule out active disease and concomitant HIV