TB Flashcards
Characteristics of mycobacterium Tb
acid fast rod aerobic slow growing intracellular
special stain for mycobacterium Tb
Ziehl Neilsen stain
when do you see mycobacterium avium
in AIDS patients when CD4 count drops below 50
Explain the path of infection of Tb
Tb is inhaled
implants in alveoli and is taken up by macrophages where it grows slowly
what happens when the macrophage infected with Tb dies
lymphohematogenous spread
What is a Gohn Complex, where is it located
Gohn complex is a calcified granuloma that occurs in a primary Tb infection.
Often located in the lower lobes.
what are te signs on CXR of a primary infection
Gohn Complex
hilar LAD
What is a Simon Foci
Graunloma in the apical and posterior part of the lungs that is the result of Tb spreading to the lungs from another organ.
Site of secondary reactivation
What are the potential outcomes of a primary pulmonary Tb infection
Host wins, time bomb, host loses
what happens if the host wins
Tb is sucesffully contained in a granuloma with little or no caseastion, and the calcification may be seen on CXR
what happens in the case of a time bomb
there is a 10% risk of reactivation, this lesion has caseation with dormant Tb.
what happens if the host loses
hematogenous spread called miliary Tb, it can spread to CNS, LN, GI, and kidney
what is Pott’s disease
When Tb spreads to the SC
what is reactivation? what is is normally preceded by, what normally reactivates
Reactivation is when a site of infection reactivates and starts to spread
this is normally preceded by a decrease in immune function.
Foci that often reactivate are apical or extrapulmonary
Pulmonary signs of a Tb infection
Rales
Consolidation
chest asymetry
