Antimic Flashcards
4 types of antimicrobials
antibiotics
antivirals
antifungals
antiparasitics
the human microbiome is made up of harmless bacteria that the body needs to function, however what can occur when these bacteria translocate to different parts of the body
infection
what is intrinsic resistance
inherent natural ability of bacteria to be resistant to abx without mutation or getting additional genes
what 4 mechanisms of intrinsic resistance exist
cellular envelope
multi drug efflux pumps
lack of drug targets
enzymes
what type of resistance involves impermeable cellular envelopes that prevent abx from entering
cellular envelope
efflux pumps are on bacterial cell walls and pump abx out, are they associated with gram positive / negative bacteria
gram negative
give one example of lack of drug targets in the context of resistance
penicillins cant be used for mycoplasma because they work on bacterial cells walls and mycoplasma has no cell wall
give an example of enzymes in the context of resistance
some bacteria produce beta lactamase destroys beta lactam rings
define extrinsic bacterial resistance
resistance due to modifications to genome due to environmental factors or gene transfer
what 2 mechanisms of extrinsic resistance exist
horizontal gene transfer and mobile genetic elements
mechanism/ type of extrinsic resistance that is characterised by exchange of genetic info between bacteria
horizontal gene transfer
mechanism/ type of extrinsic resistance that involves jumping plasmids - facilitate transfer of genes between patients
mobile genetic elements
what types of abx are mrsa resistant to
b lactamase abx’s (penicillins)
what type of abx is CRE resistant to
carbapenem based
what superbug is resistant to both penicillins and carbapenem based abx
esbl
what superbug exhibits resistance to vancomycin adn carbapenem based abx and therefore should not be used for a long time
vre
if carbapenem based abx are ineffective is there anything that can be done for those patients yes or no
no
what is meant by antimicrobial stewardship/ ams
organisation approach to promoting and monitoring safe use of antimicrobials
when assessing patients what should you look for evidence of
bacterial infections
some infections are self limiting, if patients present with a fever over 38 degrees is this usually indicative of a viral or bacterial infection
viral
sometimes starting abx can cause more harm to patients, give one example of where this can be the case
risk of c diff
risk of AMR
c diff is gram positive and grows when the gut microbiota is disturbed by abx use causing severe diarrhoea, give one treatment option
faecal transplant
before starting abx treatment a comprehensive risk assessment should be done, what things might you consider
recent abx use or immunocompromised?
would empirical treatment be done with broad or narrow spectrum abx in the short term
broad
what different cultures can be done whilst trying to focus treatment
blood urine faecal cultures
throat and wound swabs
what imaging would you expect when trying to make a diagnosis of pneumonia
CXR
lab investigations may show increased inflamm markers such as
WCC neutrophils lymphocytes CRP
lab investigations look at trends, what might an increase in inflammatory markers indicate about treatment
not working so consider switch
if sepsis is present treatment should be started within what time frame
1h
what are the risks associated with fake pencillin allergies
inc costs
longer hospital stays
trenicillin allergies are mediated by IgE and occur in first 1h of drug
give 3 ways this may manifest
hives
urticaria
anaphylaxis
names of serious life threatening systemic allergic reacs
(drug allergy)
TENS
SJS
DRESS syndrome
pustulosis
difference between allergy (hypersensitivity) and SE
allergy: immunological
SE and intolerance: pharmacological
genetic susceptibilty to ADR = X
idiosyncrasy
various mechanisms mimics allergy = X
pseudo allergy
3 things to consider after checking penA label
allergy hx
risk stratification
specialist/ non allergy specialist de-labelling