Mycobacteria

Question 1

What test is done to identify Mycobacteria within bacilli?

Answer 1

Ziehl-Neelsen

Question 2

Give examples of conditions caused by mycobacteria

Answer 2

Tuberculosis, leprosy, buruli ulcers

Question 3

How many deaths from TB in the last 200 years

Answer 3

1 billion

Question 4

Mycobacteria are slightly c____, beaded bacilli

Answer 4

curved

Question 5

Mycobacteria are resistant to Gram stain due to the high ____ content with mycolic acids in cell wall

Answer 5

lipid

Question 6

True of false: mycobacteria are anaerobic

Answer 6

False, they are aerobic

Question 7

Mycobacteria have high molecular weight cell ___

Answer 7

wall

Question 8

True or false: mycobacteria eg M. tuberculosis are fast growing

Answer 8

False, they are slow growing (makes much longer to diagnose)

Question 9

The thick ____ rich cell wall makes immune cell killing and penetration of drugs challenging

Answer 9

lipid

Question 10

How is TB transmitted?

Answer 10

Through the air from one person to another

Question 11

What is primary tuberculosis?

Answer 11

Initial contact made by alveolar macrophages with the bacilli taken in lymphatics to hilar lymph nodes

Question 12

Latent TB

Answer 12

T-cell mediated immune response, primary infection contained, no clinical disease

Question 13

Pulmonary TB

Answer 13

Granulomas form around bacilli in apex of lung
More air and less perfusion in apex so fewer WBCs
TB may spread in lung causing other lesions
(Could happen immediately or months later after primary infection)

Question 14

Name other types of TB when it spread beyond the lungs

Answer 14

TB meningitis
Miliary TB
Pleural TB
Bone and joint TB
Genito urinary TB

Question 15

Mycobacteria are phagocytosed by _____ and traffic to phagolysosomes

Answer 15

macrophages

Question 16

Mycobacteria escape into the cytosol due to adaptions to withstand the p_______ killing

Answer 16

phagolysosomal

Question 17

CD4 T-cell generate interferon g____ which helps activate macrophages to undergo intracellular killing

Answer 17

gamma

Question 18

The TB uses ______ as a Trojan horse to pass to other areas of the body

Answer 18

macrophages

Question 19

Working granulomas

Answer 19

Mycobacteria shut down metabolically in order to survive (become dormant)

Question 20

Failing granulomas

Answer 20

Forms a cavity of live mycobacteria and eventual disseminated disease

Question 21

What does the granuloma consist of?

Answer 21

Macrophages and Th1 lymphocytes (which synthesises IFN-gamma and other cytokines)

Question 22

Granulomas can become unstable by depletion of what 2 components?

Answer 22

CD4 and TNFa

Question 23

Anti-Tb drugs

Answer 23

2 months -Isoniazid, rifampicin, pyrazinamide, ethambutol
Followed by 4 months of just isoniazid and rifampicin

Question 24

How does injury activate WBCs?

Answer 24

Loss of blood causes hypoxia