Anti-mycobacterial agents Flashcards
for mycobacteria and Norcardia what type of stain is used
Acid-fast stain
T/F: Mycobacteria and Norcardia grow extremely slowly
True
What are the two mycobacteria that cause tuberculosis
M. tuberculosis and M. abscessuss (animals)
What symptoms that would raise suspicion that someone may have tuberculosis
coughing up blood and cough persists for weeks,
How long is latent and active TB treated
6 months
What drugs are multi drug resistant TB resistant to, what drugs are extensively drug resistant TB resistant to
isoniazid and rifampin/ isoniazid, rifampin, floriquinolones, and injectables
T/F: Places with higher rates of HIV can be associated with higher rates of tuberculosis
True
What are characteristics mycobacterium tuberculosis
Complex cell wall, aerobic/ anaerobic, intracellular/extracellular, resistant to many common antibiotics, no environmental reservoir
T/F: M. Tuberculosis is gram negative
False: M. Tuberculosis is neither gram positive or gram negative
What are the components of the cell wall for M. tuberculosis
small peptidoglycan component, polysacchride reigon made up of rabinose and galactose, long mycolic acid capped off with Trehatose (a sugar)
What is the first line of defense that M. tuberculosis will encounter, what occurs
Macrophages, M. tuberculosis is engulfed but does not die leading to a gathering of defensive cells
What is a granuloma
Defensive tissue formed by M. tuberculosis, has a core of infected macrophages covered by other immune systems, macrophages die and the bacteria survive and are dormant but may be reactivated
T/F: Latent Tuberculosis infections are new to the patient and do lead to a large amount of symptoms
False: Latent tubeculosis infections are present before they become latent, they are asymptomatic, the only was to know is by taking a purified protein derivative test
How often does latent tuberculosis become active tuberculosis
10% of the time
What are the two tests to find out whether a patient has tuberculosis
Tuberculin Skin Test and Quantiferon
What is the most specific way to know if a patient has tuberculosis
Quantiferon test
What is the advantage of a quantiferon test over a tuberculin skin test
Results are available after 24 hours while the tuberculin skin test requires a 48 hour follow up
What is the machine that is used to test TB, what are its advantages
Xpert MTB/RIF, takes 2 hours and tells whether the TB is resistant to rifampin
What are the two phases for treatment months of TB that is drug sensitive, how long are they
Intensive phase/two months daily, Continuation phase/ four months daily
What drugs are given during the intensive phase
Rifampin, isoniazid, pyrazinamide, ethambutol
What drugs are given during the continuation phase
isoniazid and rifampin
What drugs are used to kill dormant TB
pyrazinamide (acid enviornment only), rifampin
How does M. TB become drug resistant
Spontaneous mutations
What are the ways spontaneous mutations aid TB in drug resistance
Change the target of the drug, change the amount of the drug, change enzymes that activate the drug, changing how long drug is in cell or exited, mutations change mutation rate
