Gram Negatives Flashcards
1
Q
makeup of outside of gram negatives
A
- two cell membranes with thin peptidogylcan wall inbetween
- surface protein lipopolysaccharide
2
Q
Newer drugs are incorporating what into them?
A
- beta lactamase inhibitors to stop the bacteria from breaking it down with their beta-lactamase properties
3
Q
Pathogenic features of Gram Negatives
A
- Infections
- Endotoxins- lipopolysaccharide
- Enterotoxins - E. coli, shigella, infections diarrhea
- community and nosocomial acqusitions
- intrinsic resistance mechanisms exist in some species like beta-lactamase, efflux pumps, outer membrane
4
Q
____ has many gram (-)s which are fine unless they leave this area
A
- GI tract
5
Q
Medically Relevant Gram Negative bacteria
A
- gram neg bacilli (enterobacteraceae and non-enterobacteriaceae)
- gram neg cocci/ coccobacilli
- “Other” gram neg bacteria
- Gram neg anaerobes
6
Q
Enterobacteriaceae
A
- diverse bacterial group -thousands of species: found in normal GI flora!
- Enteric gram negative bacilli
- e. coli
- enterbacter spp.
- citrobacter spp.
- salmonella, shigella, camplyobacter
- Primary cause of clinically significant gram neg infections
- food/water borne pathogens
- e. coli
- shigella
- salmonella
- campylobacter
- vibrio cholerae
7
Q
SPACE
A
- highly drug resistant enteribacteriaceae
- cause GI infections
8
Q
E. coli
A
- most common shiga-toxin producing e. coli
- source; contaminated beef, and veggies
- low inoculum <100 cells needed for infection
- > 110,000 cases, 80 deaths/yr
9
Q
Enterobacteriaceae threat by CDC yes/no
A
yes
10
Q
Non-enterobacteracaea
A
- non-fermentative, gram-neg bacilli (rods)
- Organisms:
- pseudomonas aeruginosa
- acinterobacter baumanii
- stenotrophomonas maltophilia
- berkholderia cepacia
- not normal flora
- nosocomial infections
- multi-drug resistant infections
11
Q
Pseudomonas Aeruginosa
A
- normally colonizes soil, water, plants
- cause of both chronic and acute disease
- infections:
- SSTI/foliculitis
- endocarditis
- sepsis
- post-op wounds
- IV catheters
12
Q
Multi-drug resistant Pseudomonas Aeruginosa threat level
A
- threat level serious
13
Q
Acinetobaacter baumanii
A
- mostly found in hospitals in/on equiptment
- days to weeks duration
- infects immunocompromised hosts
- high crude mortality
- infections: pneumonia (vents), open wounds, lines
14
Q
Multi-drug resistant acinetobacter baumanii threat level
A
- threat level serious
15
Q
Clinical Pearls- Non-enterobaacteraceae
A
- cover for pseudomonas in suspected noscomial infection until pathogen identified
- double coverage used initially
- few treatment options for MDR pseudomonas and acinetobacter
- Stenotrophomonas treatment of choice: TMP/SMX
- WASH HANDS
