ID Intro Flashcards
3 variables affecting development of infection and disease
- Host
- Environment
- Agent
Gram stain fxn
- how do G + and - look?
Differentiates Gram + from Gram - bacteria
Gram Positive
- large peptidoglycan layer (up to 90% of cell wall)
- holds the dye
- Purple
Gram Neg
- thin peptidoglycan layer
- Pink
Two main bacteria in each group
- GPC
- GPR
- GNC
- GNR
Gram + cocci (GPC)
- Staph
- Strep
Gram + rods (GPR)
- Listeria
- Clostridium
Gram - cocci (GNC)
- Neisseria
- Moraxella
Gram - rods (GNR)
- E. coli
- Pseudomonas
How are infectious agents recognized by the immune system?
Security against a particular disease
Use PRR to Recognize MAMPS and DAMPS
What unique properties are found only in Gram + and only in Gram -
Gram + : teichoic acid
(found in thick cell wall/cell membrane)
Gram - : Endotoxin/LPS
(a lipopolysaccharide found w/in outer membrane, outside of thin peptido wall)
Non staining organisms with no cell wall.
List some others.
- Mycoplasma
- Chlamydia
____________
Other:
Legionella (poor)
Mycobacteria
Spirochetes
Rickettsia
Lactose fermenting GNR
#1 E. coli Klebsiella Enterobacter Citrobacter Arizona
Classic Non lactose fermentting GNR
Pseudomonas aerugonosa
Salmonella
Shigella
Gram neg Cocci
GNC
Neisseria sp
- gonorrheae
- meningitidis
Moraxella catarrhalis
Acinetobacter
(can be present after everything has been killed)
GPC
Pairs/clusters
Pairs/Chains
Pairs
Which ones are catalase +?
Pairs/clusters
- staph
Pairs/Chains
- strep
Pairs
- either
Staph is cat +, strep is -
Which of the staph is coag + and -?
+ : S. aureus
- : S. epidermidis, saprophyticus, lugdane
GPR
small
large
small:
*Listeria (preggos at risk)
Diphteroids
Large:
*Clostridium sp.
bacillus
Sources of anaerobes
Normal flora are often anaerobes
- oral
- lung
- intestines
- Female GU
3% of + blood culture
Pattern recognition receptors (PRR):
- Transmembrane (surface)
- Cytosolic
- Extracellular
Transmembrane (surface)
- TLRs
Cytosolic
- NOD, TLR
Extracellular
- CD14, LBP
Noninfectious fever
The C-C-C-C-C-Causes
- Cancer
- Chemicals
- Collagen vascular
- Clot
- Central fever
- Consider
Cell wall synthesis is target for which drugs?
B lactams (PCN, Ceph)
Glycopeptides (bacitracin, vanco)
Cell membrane is target for which drugs?
Polymyxins
Outer membrane regulates what 3 things?
B lactamases
Permeability
Efflux
Steps of gram staining
- Heat slide (kill and bind bact)
- Crystal violet (stain)
- Iodine (mordant that binds the crystal violet to Gram + cell wall)
- Decolorizer (acetone alcohol to remove stain from G- cells)
- Safrinin (counterstain)
Coagulase + staphylococci
S. aureus
Bacteria associated with endocarditis (4)
- S. viridans
- enterococcus
- S. aureus
- S. pneumoniae
Bacteria associated with meningitis (4)
- S. pneumoniae
- N. meningitidis
- Listeria
- H. influenzae
5th sign of inflammation
functio laesa
- impaired fxn
Techoic acid and Endotoxin/LPS are found in which bacteria?
Teichoic acid:
- GP
Endotoxin/LPS (outer membrane)
- GN
Fxn of Teichoic acid
Induces TNF and IL-1
- Found in GP
Which drugs have high oral bioavailability?
Quinolones
TMP/SMX
Metronidazole
True / False
Infxs dis can be acute or chronic
Infxs dis are NOT always contagious
Colonization is NOT equal to disease
True to all
Bacteremia is typically caused by which org?
Staph! its bad
~ 100%
- if S. epi is present, its prob just a contaminant.
