Term
How is Staph differentiated from strep?
How is S. aureus distinguished from all other staphylococci? |
|
Definition
Strep grow in chains
Strep are Catalase(-)
No other staph species are coagulase(+) |
|
|
Term
| What are the laboratory characteristics of Staph aureus? |
|
Definition
Gram(+) cocci in grape-like golden clusters
Beta-hemolytic on blood agar
Coagulase and Catalase (+) |
|
|
Term
How many types of Staphylococcal enterotoxins are there?
What is the pathogenesis of the toxins? |
|
Definition
6 distinct serological types
Pathogenesis
Induces Peristalsis and Diarrhea
Stimulates Vomiting
Superantigen activity causing toxic shock syndrome |
|
|
Term
What are the lab characteristics of Bacillus cereus?
What typical foods does bacillus cereus affect? |
|
Definition
Lab: Aerobic, Large spore-forming, Gram(+) Rods
Foods: Rice, or meat dishes
|
|
|
Term
What are the food poisoning syndromes that are produced by Bacillus cereus?
What are the causative toxins?
What foods are they typically found in?
Which syndrome appears faster? |
|
Definition
Emetic(similar to staph food poisoning)
Heat-stable Enterotoxin
Found in grains and rice
Appears faster(in 4 hrs) similar to Staph
Diarrheal Type(Similiar to Cholera and E.coli)
Heat-labile Enterotoxin increasing cAMP
Meat, Vegetables and Sauces
Takes longer to appears(24 hrs) |
|
|
Term
What are the lab characteristics of Clostridium botulinum?
What foods does it typically affect? |
|
Definition
Anaerobic Gram (+) Spore-forming Rod
Alkaline, Anaerobic(Canned) Vegetables |
|
|
Term
What is the structure, and mechanism of Botulinum toxin?
How many serotypes are there |
|
Definition
Structure: AB
Mechanism: Prevents Ach release causing flaccid paralysis
Serotypes: 8
|
|
|
Term
What is the different syndromes caused by Clostridium Botulium?
Which is most common? |
|
Definition
Food Borne:
12-36 hrs onset of GI Symptoms
Followed by descending paralysis
Wound Botulism
4-14 days same presentation w/o GI symptoms
Infant Botulism(Most Common)
Honey-> Floppy Infant Syndrome |
|
|
Term
| What ar ethe treatment modalities for Botulism and when are each implemented? |
|
Definition
Respiratory Support: as needed
Penicillin:
Not to Infants
Only if organisms present
Antitoxin:
Not to infants
Food-borne and wound botulism
Botulism Immune Globulin Intravenous:
Human Ig for infant botulism A and B
|
|
|
Term
What is the mechanism of:
Shiga Toxin
Cholera Toxin
LT enterotoxin
ST enterotoxin
E.coli cytotoxin
Botulinum toxin
Staph Enterotoxin
B.cerues Heat stable
B.cereus Heat-labile
Y.enterolytica Enterotoxin |
|
Definition
Shiga Toxin: AA-tRNA Receptor site block
Cholera Toxin: AB with ADPR-transferase for AC increasing cAMP
LT enterotoxin: AB ADPR-transferase for AC
ST enterotoxin: Activates GC
E.coli cytotoxin: Shiga like toxin
Botulinum toxin: block Ach release
Staph Enterotoxin: Peristalsis/Vomit/Superantigen
B.cerues Heat stable: Staph enterotoxin like
B.cereus Heat-labile: cAMP like Cholera
Y.enterolytica Enterotoxin: E.coli ST like |
|
|
Term
| What are the noninvasive and Invasive common GI pathogens |
|
Definition
Non-Invasive
C. diff
Cholera
EHEC
ETEC
H. pylori
Invasive
Shigella
Salmonella
EIEC
V.parahaemolytics
Yersina enterolytica
Campylobacter jejuni
|
|
|
