Lecture 5 9/20/23 Flashcards
What is environmentally-mediated resistance?
physical and chemical characteristics of environment alter drug or physiological response of microbe
What is intrinsic microorganism-mediated resistance?
pre-existing property of microbe provides resistance
What is acquired microorganism-mediated resistance?
resistance resulting from altered cellular microbial physiology and structure due to genetic changes
How can microorganism-mediated resistance be acquired?
-mutation
-horizontal gene transfer
What are the mechanisms of antimicrobial resistance?
-prevention of penetration to target sites within microbe
-rapid efflux of antibiotics
-enzymatic destruction/inactivation of drug
-modification/protection of drug’s target site
What are the reasons for emergence of resistance?
-widespread antimicrobial use
-microbial adaptation/change
-demographical changes
-medical advances (implants/caths good sites for biofilms)
-ecosystem changes
-cutbacks in public health systems
What is the potential impact of antimicrobial resistance?
-increased mortality
-increased vet visits
-high treatment costs
-productivity loss
-economic impact
-zoonotic spread of resistance
-increased nosocomial infections
How do providers contribute to resistance?
-over-prescription
-over-selection of broad spectrum, last-resort drugs
How do patients/clients contribute to resistance?
-non-compliance
-self medication/OTC availability
How does industry contribute to resistance?
-misleading promotions
-competition between brands
How can drug use be used to reduce resistance?
-maximize efficacy of therapeutic regimen
-restrict extra-label use
-observe withdrawal period
-use separate antimicrobials for humans and animals
-consider alternative therapies
How can pathogen control be used to reduce resistance?
-manage animal waste
-reduce contamination during slaughter and processing
-maintain herd health and infection control
How can policy be used to reduce resistance?
-control drug use in food animals
-monitor resistance on national scale
-educational efforts
What is antimicrobial stewardship?
actions taken to preserve the success and availability of antimicrobials
What are Koch’s postulates?
-microbe must be found in abundance in organisms suffering from disease, but not in healthy organisms
-microbe must be isolated from diseased organism and grown in pure culture
-cultured microbe must cause disease when introduced to healthy organism
-microbe must be re-isolated from inoculated organism and shown to be the same as original causative agent
