TB Flashcards
What is a sign of active TB?
damage to lung tissue
also blood-tinged sputum
What stain do you use for Tb? Why?
acid-fast due to mycolic acids
What virulence factor of TB activates the granuloma?
cord factor
What virulence factor of TB inhibits phagolysosomes?
sulfatides
Glycolipids in TB
virulence factor
prevent phagolysosome fusion
What 3 host factors are critical to killing TB ?
Th1 factors (ex: IFN-y)
CD4 T-cells
Macrophage activation
What is a granuloma?
organized structure of macrophages, lymphocytes and neutrophils
What is the histopathologic hallmark of TB?
caseating granuloma
What surrounds the caseating granuloma?
Langhans giant cells
IGRA
test for TB
the same as quantiferon gold test
TST
test for TB
the same as PPD
What is true of PPD and quantiferon gold?
once infected with TB they are always positive
Which TB test does not react with the BCG vaccine?
quantiferon gold
Rifampin MOA
inhibit bacterial DNA-dependent RNA polymerase
Isoniazid MOA
inhibit mycolic acid synthesis (cell wall synthesis)
Pyrazinamid MOA
?
disrupts plasma membrane
Ethambutol MOA
inhibits arabinosyl transferase (cell membrane)
Which drug can cause rash and red-orange secretions?
Rifampin
Which drug can cause optic neuropathy?
ethambutol
What are 2 airbone precautions for TB?
N95 masking
negative pressure room
What is a problem if you have HIV and TB at the same time?
Rifampin upregulates enzymes that could break down your HIV regimen drugs
How do you treat active TB overall?
RIPE
4 for 2 months
2 for 4 months
What is a public health aspect of TB?
you are mandated to report a case of TB to your county’s health department
DOT
direct observed therapy
required in TB patients
cervical lymphadenopathy in toddlers indicates …
MAC: mycobacterium avium …
there is no drug treatment for MAC
NTM stands for …
non-tuberculosis mycobacterium
Which 2 NTM mycobacterium are rapid growers?
M. abscessus
M. fortuitum
all others are slow growers, including MAC
