Microbiology and Antimicrobials Flashcards
what is gram positive colour
purple
name a gram negative bacteria
prevotella intermedia
what is capnophilic
carbon dioxide
what is facultative
live with and without oxygen
when does antimicrobial resistance occur
when microorganisms such as bacteria, viruses, fungi and parasites change in ways that render the medications used to cure infections they cause ineffective
what are the 2 types of resistance genes
intrinsic (structural)
acquired (mutations)
what are the 3 types of mutation a microbe can go through
transformation/transduction/conjugation
what are the 3 mechanisms of antibiotic resistance
altered target site
enzymatic inactivation
decreased uptake
name a microbe which has resistance by altered target site
streptococci
name 2 microbes which have resistance by enzymatic inactivation
prevotella and fusobacterium
how does altered target site work
bacteria change penicillin binding proteins
how does enzymatic inactivation work
bacteria produce enzyme (beta-lactamase) which destroys the antibiotic
how do you treat an extended spectrum beta-lactamase infection
carbapenems
what are the 2 main microbes associated with acute pyogenic dental infections
streptococcus anginosus
prevotella intermedia
what is the ideal specimen for dental infections
aspirated pus
what are the treatment principles for dental infections
localise infection
establish diagnosis
remove source
what anaerobes are involved in pericoronitis
prevotella intermedia
streptococcus anginosis
how do you treat pericoronitis
locally (scale)
systemically (metronidazole)
what microbes are involved in ORN
anaerobic gram negative rods
anaerobic streptococci
strep anginosus
staph aureus
what anaerobes are involved in salivary gland infection
staph aureus and anaerobes
how do you treat salivary gland infection
drainage
flucloxacillin and metronidazole
what anaerobe is involved in ludwigs angina
prevotella intermedia
what is sepsis
life threatening organ dysfunction caused by dysregulated host response to infection
what signs tell you that the patient has sepsis
SIRS signs and infection (suspected or confirmed)
what are the treatment principles of sepsis
primary care - know red flag signs
secondary care - diagnosis, sepsis 6, NEWS
what does SIR mean in antibiotic resistance testing
S - susceptible at standard dose
I - susceptible but need increased exposure or dose
R - resistant even with increased exposure or dose
what is automated susceptibility testing system
isolate bacteria
put test strips into machine
quantitative data produced
what is a breakpoint in automated susceptibility testing system
chosen concentration of antibiotic which defines whether a species of bacteria is susceptible or resistant to the antibiotic
what are the confounding variables when testing for antibiotic resistance
inoculum size
pH
phase of growth
biofilm
atmosphere
co-morbidities
pus collections
site of infection
foreign bodies
biofilm
what should be the firs principle of management when dealing with dental infections
surgical drainage
what is anti-microbial stewardship
team working to reduce antimicrobial use
what actions promote using antimicrobials responsibly
hand hygiene
team work
data management
what strategic objectives are in place to reduce use of antimicrobials
reduce incident
reduce need for unintentional exposure to antimicrobials
how do we reduce the amount of antimicrobials given out
infection prevention
antimicrobial stewardship
decreasing prescriptions
what is pen v most effective against
oral streptococci
anaerobes
selected gram negative
what is amoxicillin most effective against
broader spectrum than pen V so greater impact on selection of resistant microflora
what is dental stewardship
keep antibiotics for infections
use pen V as first line
use for 5 days duration
