Microbiology & Antimicrobials Flashcards
Difference between GRAM+ & - bacteria
Gram-Positive Bacteria:
- Thick peptidoglycan layer in the cell wall
- Retains violet crystal dye during Gram staining (PURPLE)
Gram-Negative Bacteria:
- Thinner peptidoglycan layer in the cell wall
- Outer membrane has lipopolysaccharides (LPS)
- Loses violet crystal dye during Gram staining (PINK/RED)
what does facultative mean?
can use BOTH oxygen & no oxygen to survive and produce energy
what is a mechanism of antibiotic resistance?
- altered target site
what is another mechanism of antibiotic resistance?
- enzymatic inactivation
give an example of a bacteria that is resistant to antibiotics using ALTERED TARGET SITE?
viridans group streptococci
(S. mitis, S. mutans etc)
give an example of a bacteria that is resistant to antibiotics using ENZYMATIC INACTIVATION?
Prevotella & fusobacterium species
what does ESBL stand for?
Extended spectrum beta-lactamase
how can you treat an ESBL infection?
Using CARBAPENEMS
(last option for MDR [multi drug resistance] infections)
what can be found in aspirated pus?
- endogenous infection
- often mixed infections
- strict anaerobes important (S. anginosus, P. intermedia)
what can be found in a periodontal abscess?
anaerobic streptococci
Prevotella intermedia
What is the microbiology for osteomyelitis of the jaw?
- anaerobic Gram-ve rods
- anaerobic streptococci
- streptococcus anginosus
- staphylococcus auereus
what YOU MUST do in an infection situation?
1) Document your diagnosis
2) Document antibiotic choice, dose, route & duration
3) Document review date
4) Document deviation from guidance (If necessary)
What is severe odontogenic infection (SOI)
Severe infection resulting from teeth where it spread into tissue planes,
Includes: Systemic symptoms + Signs of SEPSIS
what is ludwigs angina?
BILATERAL INFECTION -> SWELLING OF SUBMANDIBULAR SPACE
- Most common bacterial infection
- Anaerobic Gram-VE bacilli
- Streptococcus anginosus
- Anaerobic streptococci
How is sepsis officially diagnosed?
SIRS + Suspected/confirmed infection
What is SIRS abbreviation and does each mean?
Systemic Inflammatory Response Syndrome
1. Temp <36 or >38*C
2. Pulse >90/min
3. Resp Rate >20/min
4. WCC <4 or >12
what is sepsis?
life threatening organ dysfunction caused by dysregulated host response to infection
how is sepsis diagnosed in primary care?
How is sepsis treated in secondary care?
Sepsis 6:
1. give high-flow oxygen
2. take blood cultures
3. IV antibiotics
4. Give fluid challenge
5. Measure lactate
6. Measure urine output
Get help
what is the definition of clinical resistance?
when infection is highly unlikely to respond even to maximum doses of antibiotic
what is antimicrobial stewardship?
team working to preserve antimicrobial medicines by taking measures to promote their control.
Focuses on prescribers of antibiotics, doctors, dentists etc
what are the 5 strategic objectives by the WHO to help combat antimicrobial resistance?
- improve awareness & understanding
- strengthen the knowledge through surveillance and research
- Reduce the incidence of infection
- Optimise the use of antimicrobial medicines
- Ensure sustainable investment
what is the spectrum of antimicrobial activity for Pen V?
- most active against oral streptococci, anaerobes & selected gram-ve cocci
what is the spectrum of antimicrobial activity for amoxycillin?
Same spectrum as Pen V
PLUS
more effective against gram-ve cocci & members of the family enterobacteriaceae
are antibiotics effective for toothache?
No, they dont cure toothache
should be reserved for cases with signs & symptoms of SPREADING infection
What is the current regimen for Phenoxymethylpenicillin (Pen V)?
500mg
4 times a day
5 days
when should metronidazole be used over Pen V?
(IF PEN V ALLERGY)
OR
Periodontal infections (Pericoronitis, Necrotising ulcerative ginvititis)
