Pharm - Antimicrobial Intro Flashcards
(68 cards)
define antibiotic
molecule that kills OR stops (arrests)growth of bacteria
further classify “chemotherapeutics”
includes anticancer and antimicrobials
antimicrobials include antibiotics, as well as anti viral, antifungal, anti parasite
true or false
antibiotics are SPECIFICALLY antibacteria
true
true or false
antimicrobials include solely antibiotics
FALSE
also antifungals, anti parasites, etc
name 5 bacterial/fungal/viral targets
enzymes
DNA synthesis
metabolism
cell wall
ribosome
what are the methods of DNA synthesis in bacteria
could be chromosomal or plasmid
true or false
humans and bacteria have relatively the same enzymes
false - different
that’s why they can be a target for antibiotics
why is it important to design antibiotics to target bacterial-specific features
to limit human toxicity
we don’t want to target and kill/suppress growth of our own cells
name 3 things that can be a “reservoir” for the causative agent (bacteria/fungus/virus)
animal
plant
inanimate object (fomite)
name 4 ways the causative agent can exit the reservoir
blood
intestinal tract
respiratory tract
skin
name 3 things that make a host susceptible to infection
age
chronic illness
immunocompromised
what is the “vector” mode of transmission
through animals/insects
name 5 “portals of entry” for the causative agent
blood
intestinal tract
respiratory tract
non-intact skin
mucous membranes
what is antimicrobial susceptibility testing
you obtain a specimen from the patient and check its susceptibility to various antimicrobial agents to see which antibiotic will work for the infeciton
involved with antimicrobial stewardship to prevent resistance. want to choose the correct drug
explain what “MIC” and “MBC” are
MIC = minimum inhibitory concentration. it is the lowest concentration of the medicinal agent that prevents visible growth
MBC = minimum bactericidal concentration. same concept, this term is just used if the antibiotic is bacterioCIDAL and not static
name 3 methods of susceptibility testing
broth/agar dilution
disk diffusion (kirby-bauer method)
gradient diffusion (Etest)
who defines the 3 methods of antimicrobial susceptibility testing
USp
what is “ZOI”
used in disk diffusion/Kirby-Bauer test of antimicrobial suceptibility
refers to the diameter of the “clear” area around the antimicrobial disk in which the antibiotic was killed/growth was inhibited
Drug A has large ZOI
Drug B has small ZOI
which drug is better suited for the patient’s infection
Drug A
explain the specializes assay for seeing if a patient has beta lactamase, and thus resistance to beta lactams
uses a chromogenic beta lactam substrate
if the beta lactam ring is cleaved and the pt does in fact have beta lactamase, the cells will turn BLUE. if not, they will be green as the molecule is still intact
explain how you can use a specialized assay to test for MRSA (methicillin resistant staph aureus)
PBP2 exists in a patient in which staph aureus is susceptible to methicillin
however, in MRSA, this protein is instead a LOW AFFINITY PBP – called 2’ (2a) or PBP2’ (PBP2a)
this is extracted from MRSA and mixed with a latex reagant + a monoclonal antibody against PBP2a. If CLUMPS FORM, it indicates MRSA
which antigen is used to diagnose strep throat
Strep A ohydrate antigen
name 3 different ways in which antibiotics can be classified
-the class and spectrum of the microorganism it kills
-the biochemical pathway it interferes with
-the chemical structure of its pharmacophore
as mentioned, 1 way antibiotics can be classified as as the “class and spectrum” of the microorganism it kills
give an example
antibacterial broad spectrum
or
antibacterial gram positive/negative
