TB

Question 1

what is the strongest risk factor for developing active TB

Answer 1

• HIV

Question 2

what appears to accelerate the progression of HIV disease?

Answer 2

• TB

Question 3

MDR TB defined as resistant to which drugs?

Answer 3

• INH (isoniazid)

- RIF (rifampin)

Question 4

XDR TB defined as

Answer 4

• MDR strain resistant to two classes of second line drugs

Question 5

the BCG vaccine is which organism

Answer 5

• mycobacterium bovis

Question 6

what kind of pathogen is mycobacterium tuberculosis

Answer 6

• facultative intracellular acid fast pathogen

Question 7

MTB lives primarily where

Answer 7

• in macrophages

Question 8

what kind of stain do you use for TB

Answer 8

• acid fast stain

Question 9

what is the defining and unique feature of the mycobacterial cell wall

Answer 9

• mycolic acid

Question 10

what does mycolic acid form

Answer 10

• myobacterial outer membrane

Question 11

is there LPS in mycobacteria

Answer 11

• no LPS

Question 12

MTB is transmitted by

Answer 12

• aerosols

Question 13

how can MTB survive in macrophages?

Answer 13

• resistance reactive oxygen and reactive nitrogen species

- arrests phagosome maturation at a very early step

Question 14

what kind of response leads to macrophage activation and MTB control?

what presents the antigen?

Answer 14

• TH1

- TB infected macrophages and dendritic cells

Question 15

what are recruited to the site of infection in MTB control

Answer 15

• antigen specific CD4 and CD8 T cells

Question 16

do antibodies play a role in MTB infection

Answer 16

• no

Question 17

what happens after MTB infected macrophages are recognized by antigen specific CD4 and CD8 cell?

Answer 17

• cytokine production that activates macrophages to control MTB replication

Question 18

which cytokine controls the TH1 response

what is it released by

what is the result of its release

Answer 18

• IL-12
• MTB infected macrophages
• leads to CD4 differentiation along TH1 path

Question 19

what activates macrophages

what is it secreted by

what other chemical also helps to activate macrophages

Answer 19

• interferon gamma
• CD4 TH1 type T cells and CD8 T cells
• TNF-alpha

Question 20

role of activated macrophages

Answer 20

• exhibit more efficient phagosome-lysosome fusion, reactive oxygen and nitrogen species

Question 21

what do activated macrophages wall themselves into

Answer 21

• a granuloma

Question 22

what is at the center of the granuloma

what composes the outside of the granuloma

Answer 22

• central region of macrophages, fused macrophages, extracellular bacilli, dead macrophage debris
• newly recruited activated macrophages and T cells (CD4 and CD8)

Question 23

what is the granuloma walled off by

name of the final product

importance of this

Answer 23

• fibrin coat
• tubercle
• what you can see on the X ray

Question 24

what is LTBI

Answer 24

• latent TB infection kept under control by cell mediated immune response

Question 25

what is active TB

Answer 25

- reactivation of TB occurs and triggers an overly robust cell mediated immune response leading to lung damage and symptoms of infectious TB

Question 26

what happens in the cell that can help us realize the transition to active TB

Answer 26

- granulomas liquifying and becoming and becoming a site for extracellular replication of TB

Question 27

symptoms of TB are due to

Answer 27

- cytokine production (IL-1, TNF-alpha) - macrophage activation - CTLs

Question 28

TB in HIV+ individuals why

Answer 28

- primary infection not contained allowing MTB dissemination throughout the body leading to milliary TB they don't have enough T cells to wall off TB

Question 29

miliary TB differential diagnosis include

Answer 29

- fungi | - metastatic tumor

Question 30

chance of TB reactivation after HIV infection

Answer 30

- 10% each year

Question 31

IGRA test measures

Answer 31

- IFN gamma production by T cells upon recognition of TB specific antigens not found in BCG

Question 32

MTB/RIF test measures

Answer 32

- PCR for detection of MTB | - also determines rifampicin resistance

Question 33

which TB drugs are pro-drugs first

Answer 33

- INH (Isoniazid) | - PZA (Pyrazinamide)

Question 34

cause of leprosy

Answer 34

- Mycobacterium leprae

Question 35

forms of leprosy and type of response

Answer 35

- tuberculoid leprosy (TH1 response) | - lepromatous leprosy (TH2 response)

Question 36

which form of leprosy is deformity due to nerve damage with its consequent ulcers and resorption of bone

Answer 36

- tuberculoid leprosy

Question 37

which form of leprosy is activated nodulous lepromatous leprosy

Answer 37

- lepromatous leprosy

Question 38

atypical mycobacteria common where in the US

Answer 38

- southern and midwestern US

Question 39

mycobacterium avium complex found where

Answer 39

- water supply

Question 40

mycobacterium avium transmitted by

Answer 40

- inhalation or ingestion

Question 41

mycobacterium avium causes

Answer 41

- pulmonary or disseminated disease

Question 42

mycobacterium abscessus frequent in which patients

Answer 42

- bronchiectasis, COPD and CF patients

Question 43

mycobacterium abscessus causes which infection

Answer 43

- chronic lung infection | - skin/soft tissue infections

Question 44

mycobacterium abscessus treatable with drugs?

Answer 44

- highly resistant to drugs

Question 45

mycobacterium fortuitum infections associated with

Answer 45

- nail salons & tattoo parlors