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D1S U1 Microbiology > Staphylococcus > Flashcards

Flashcards in Staphylococcus Deck (14):
1

S. Aureus will test coagulase _____

Positive

2

Most common causative agent of disease

S. Aureus

3

_____ is a key player in the extracellular matrix function of adhesion of S. aureus.

Fibronectin

4

Toxic oxidative substances released by PMNs (WBCs) to kill bacteria. Also damages host tissue (inflammation)

ROS (reactive oxygen species)

5

Virulence factors of S. aureus:

1. Polysaccharide capsule- blocks phagocytosis
2. Protein A- blocks antibody function
3. Pore-forming toxins- pop PMNs and other cells leading to more damage and inflammation (Panton-Valentine Leukocidin)

6

Syndrome where exfoliating toxins cause layers of epidermis to separate. (Toxins: Proteases with high-specificity for desmosomal proteins)

SSSS (Staphylococcal Scalded Skin Syndrome)

7

TSST-1 is a ______ (causes an unregulated inflammatory response by activating high numbers of CD4 T cells)

Superantigen

8

In Staphylococcal food poisoning, toxin is pre-formed in contaminated, unrefrigerated food. It is not an ______, rather an _____.

Infection

Intoxication

9

Many strains of S. aureus secrete enterotoxins that are heat stable:

1. Enterotoxins A, B, C, D, E
2. Superantigens- cause intense peristalsis

10

____ antimicrobial agents are inhibitory substrates for PBPs (Penicillin Binding Proteins- make peptidoglycan crosslinks). These include Penicillins, Cephalosporins, Carbapenems, Monobactams.

Beta-lactam

11

MSSA (Susceptible) vs. MRSA: Since MRSA (Methicillin Resistant S. aureus) is resistant to Beta-lactam drug classes, ____ is frequently used to treat MRSA. It is a glycopeptide class antimicrobial drug.

Vancomycin

12

Less than ___% of the population carry MRSA, but ___% of healthcare professionals carry it. Colonization sites include Nares, Axilla, and Groin.

1

5-15

13

Staphylococcus:
1. Gram stain?
2. Oxygen dependence?
3. Can it be isolated? How?

1. Gram positive
2. Facultative Anaerobes
3. Yes. 42 valid species isolated by Catalase positive test and 7.5% NaCl growth

14

S. Aureus diseases:

1. Integumentary and wounds
2. Bacteremia
3. Aspiration pneumonia
4. UTI
5. Toxic shock syndrome
6. Scalded skin syndrome
7. Food poisoning