Intro to Antimicrobials Flashcards
1
Q
acquired drug resistance
A
- drug fails to reach target
- drug is inactivated
- drug target is altered
2
Q
bactericidal
A
kills the bacteria
3
Q
bacteriostatic
A
suppresses bacterial growth
4
Q
empiric therapy
A
treatment without formal identification of specific pathogen
- used in critical conditions or when diagnosis is likely to be unnecessary or cost-prohibitive
- treat with antimicrobal agents likely to be effective– consider local bacterial resistance patterns, broader spectrum agents, culture prior to treatment
- evaluate effectiveness and reassess
5
Q
definitive antimicrobial therapy
A
identification of a specific pathogen prior to treatment
- gram stain
- growth and drug sensitivity tests
- evaluate effectiveness and reassess
6
Q
host determinants
A
- immune function
- pharmacokinetics
- age
- pregnancy
- genetics/idiosyncrasy
- allergy
- epidemiologic exposure
- compliance
8
Q
minimal bacteriocidal concentration (MBC)
A
- the minimal plasma concentration needed of a bactericidal antimicrobial to achieve effective killing of pathogen
- peak concentration is most important factor for bactericidal agents
9
Q
minimum inhibitory concentration (MIC)
A
- minimal plasma concentration of a bacteriostatic antimicrobial needed to inhibit further growth of a pathogen
- general rule that antibiotic in blood should exceed MIC by 2-8 times to offset tissue barriers to infection site
- time above MIC is most important factor for bacteriostatic agents
10
Q
inherent drug resistance
A
j
12
Q
nosocomial
A
-healthcare-associated infection
13
Q
post-antibiotic effect
A
- persistent suppression of microbial growth after antimicrobial agent has been cleared
- long PAE with intracellular bacteriostatic agents but short PAE with B-lactams
- might make length of dosing interval vs. the drug half-life less of a concern
14
Q
selective toxicity
A
- ability of ideal antimicrobial agent to act selectively on pathogen, not host
- achieved due to: unique cellular structures, unique biochemical pathways, common pathways but altered component affinities, and prodrug converted by pathogen
15
Q
transduction
A
- a process by which bacteria can inject DNA, including DNA that provides resistance to certain ATBs, into other bacteria
- bacteria and viruses need not be of the same species to do this
- one mechanism by which multi-drug resistance develops
16
Q
transformation
A
- another mechanism in which one bacteria takes up the DNA of another bacteria
- can also lead to development of drug resistance
17
Q
superinfection
A
- appearance of secondary infection during chemotherapy of a primary infection
- need to stop primary infection and treat
- normally due to elimination of normal flora with ATB treatment
