microbiology Flashcards
What colour is gram positive
purple
what colour is gram negative
red/orange
What is the name of round shape bacteria
cocci
What is S.Anginosus
gram positive bacteria that reside in the human oral cavity, cocci shaped
What is Veillonella species
Gram negative bacteria, cocci shaped
What is Actinomyces israelii
gram positive bacilli bacteria that cause chronic inf
Whta is Preevotella intermedia
Gram negative bacilli bacteria
What does capnophilic mean
Needs CO2 to survive
What is meant by faculative
Can survive with and without O2
What does Metronidazole work on
Strict anaerobes
wHAT ARE THE 2 FORMS OF RESISTANCE
INTRINSIC AND ACQUIRED
What is intrinsic resistance
when a bacterial species is naturally resistant to a certain antibiotic or family of antibiotics, without the need for mutation or gain of further genes
What is acquired resistance
resistance gained from mutation or acquisition of new DNA
What are some mechanisms of antibiotic resistance
Altered target site
Enzymatic inactivation (enzyme destroys antibiotic)
What is beta lactamase
Group of resistance mechanisms in bacteria
What does endogenous inf mean
inf derived from our own flora
What is often a mixed infection
dental abscess
What bacteria is involved in a perio abscess
Anaerobic streptococci
Prevotella intermedia
What is involved in pericoronitis
Predominantly mixed oral anaerobes, e.g, P. intermedia
S. anginosus group
Osteomyelitis of the jaws can be predisposed by what
Biphosphonate therapy (BRONJ/MRONJ)
Impaired vascularity of bone (radiotherapy, Pagets disease)
Foreign bodies (implants)
Compound fractures
Impaired host defences (diabetes)
What is involved in osteomyelitis
Anaerobic Gram negative rods
Anaerobic streptococci
Streptococcus anginosus
Staphylococcus aureus
What is ludwigs angina and SOI
Bilateral infection of Submandibular space
Most common bacteria:
-Anaerobic Gram negative bacilli
-Streptococcus anginosus
-Anaerobic streptococci
What is sepsis
Life-threatening organ dysfunction caused by dysregulated host response to infection
What is SIRS
Systemic Inflammatory Response syndrome, an exaggerated defense response of the body
- Temp <36 or 38C
- Pulse >90/min
- Resp rate >20/min
- WCC <4 or >12
What does S, I & R mean for a choice of antibiotic
S = Susceptible at standard dosing regime
I = Susceptible but need Increased exposure (increased dose)
R = High likelihood of therapeutic failure even when there is increase exposure
What is meant by the breakpoint
Abreakpoint= chosen concentration (mg/L) of anantibioticwhich defines whether a species of bacteria is susceptible or resistant to theantibiotic
What is meant by clinical resistance
When infection is highly unlikely to respond even to maximum doses of antibiotic
What are confounding variables of resistance
Laboratory:
Inoculum size
Planktonic phase
Biofilm
Clinical:
Pus collections
Forgein bodies
Site of infection
biofilm
What does antimicrobial stewardship mean
an organizational or healthcare-system-wide approach to promoting and monitoring judicious use of antimicrobials to preserve their future effectiveness
What is Pen V good against
most active against oral streptococci,anaerobes & selected Gram-negative cocci
What is a bioflim and what does it make it resistant against
an aggregate of microorganisms in which cells adhere to each other on a surface
These adherent cells are embedded within a self-produced matrix of extracellular polymeric substance (EPS) – DNA, proteins, polysacharyde.
Resistance to antibiotics, antibacterial agents, hidden from immune system of the host.
