4 Tuberculosis Flashcards
What is the worldwide prevalence of TB (latent and active)?
33%
Prevalence of TB increases with higher rates of _______ and _____.
poverty and HIV
What microorganism causes TB?
Mycobacterium tuberculosis
What test do you use to identify M. tuberculosis?
acid-fast stain
TB is transmitted through what?
droplets
In high prevalence areas, how many people can TB be spread to by an infected individual?
20 contacts infected per index case
What determines exposure risk for getting TB?
Exogenous factors like intimacy of contact with infected person, how infectious is the person, and is it a high prevalence area
What are the four possible outcomes of TB exposure?
Clearance, latent infection, primary disease, or recurrent disease
In what population(s) is primary TB most common?
children
What are endogenous factors that determine risk for developing disease?
immunity and co-morbid conditions
Who is at the highest risk for reactivation of latent TB?
HIV infected people
jejunoileal bypass patients are second most at risk
Where does MTB replicate?
inside macrophage phagosomes
What is a granuloma, and what kinds are there?
Granuloma = immune cells attempting to quarantine MTB *Kinds = caseous, non-necrotizing, and fibrotic
Active TB can present in what organs?
virtually any organ including CNS and bones
A TB skin test is testing for what?
latent TB
