export_ssti bacteria i

Question 1

Minimum diagnostic criteria for skin/soft tissue infection (SSTI)

Answer 1

Erythema
Edema

Warmth

Pain/tenderness

Question 2

Impetigo features

Answer 2

Superficial
“Honey crusts”

Most commonly around the mouth

Most common bacterial infection in children

Question 3

Bullous impetigo features

Answer 3

Blisters are cloudy, can rupture

Question 4

Bullous impetigo virulence

Answer 4

Exfoliative toxin of S. aureus

Question 5

Ecthyma

Answer 5

Deeper form of impetigo, scarring and ulceration

Punched-out ulcerative lesions

Question 6

Furuncle (boil) causative agent

Answer 6

S. aureus

Question 7

Furuncle features

Answer 7

Abscess of hair follicle

Large, painful, raised nodules

Question 8

Carbuncle

Answer 8

Multiple furuncles that coalesce

Question 9

Carbuncle defining feature

Answer 9

Chills and fever

Question 10

Folliculitis

Answer 10

Infection of hair follicles

Various bacteria and fungi

Question 11

Erysipelas

Answer 11

Acute skin infection

Involved skin is distinct from uninvolved skin

Question 12

Erysipelas cause

Answer 12

S. pyogenes

Question 13

Cellulitis

Answer 13

Involved skin is NOT differentiated from uninvolved skin

Question 14

Paronychia

Answer 14

Superficial infection or abscess of nailfolds

Acute or chronic

Question 15

Acute paronychia

Answer 15

Acutely painful abscess in nailfold

Most common cause is S. aureus

Question 16

Chronic paronychia

Answer 16

Longer than 6 weeks

Often the result of a C. albicans infection

Question 17

Necrotizing fasciitis

Answer 17

Destruction of muscle and fat
Toxicity, multiorgan failure, death

Antibiotics and surgical debridement

Question 18

S. aureus features

Answer 18

Gram-positive cocci
Catalase positive

Found in skin/mucous membranes

Coagulase positive (unlike other Staph)

Beta-hemolytic

Question 19

Strep. pyogenes features

Answer 19

Gram-positive cocci

Catalase negative

Question 20

Pseudomonas aeruginosa features

Answer 20

Gram-negative rod

Question 21

S. aureus virulence factors

Answer 21

Capsule
Biofilm

Teichoic acid

Protein A

Cytotoxins

Exfoliative toxins

Enterotoxins

TSST

Extracellular hydrolases

Question 22

S. aureus peptidoglycan

Answer 22

Endotoxin-like activity

Question 23

S. aureus teichoic acid

Answer 23

Adhesion

Question 24

S. aureus protein A

Answer 24

Inhibits Ab mediated clearance by binding IgG Fc domain

Question 25

S. aureus alpha cytotoxins

Answer 25

Pore-forming toxin | Allows for bacteria to get into cell, as well as resulting in lysis

Question 26

S. aureus exfoliative toxins

Answer 26

ETA and ETB | Serine proteases that split interepidermal junctions

Question 27

S. aureus enzymes

Answer 27

Hydrolyze host tissue to aid in the spread of the bacteria in the body

Question 28

S. aureus diseases

Answer 28

``` Toxin mediated (scalded skin syndrome, food poisoning) Suppurative (impetigo, folliculitis, etc.) ```

Question 29

S. aureus scalded skin syndome (SSSS) virulence

Answer 29

Caused by ETA and ETB

Question 30

Important diagnostic features of SSSS

Answer 30

Staph not culturable from skin (toxin mediated) | No leukocytes

Question 31

Nikolsky sign

Answer 31

Minimal pressure results in skin exfoliation

Question 32

MRSA

Answer 32

Methicillin-resistant S. aureus

Question 33

MRSA virulence factor

Answer 33

MecA gene 

Question 34

MecA gene

Answer 34

Encodes a new penicillin-binding protein on methicillin, etc. which results in a low affinity to the bacteria

Question 35

Treat MRSA

Answer 35

Vancomycin

Question 36

Treatment for S. aureus infections

Answer 36

Nafcillin | Oxacillin

Question 37

Osteomyelitis

Answer 37

Bone pain Fever Swelling Malaise

Question 38

Osteomyelitis cause

Answer 38

Almost always by a bacterial infection

Question 39

Septic arthritis features

Answer 39

Painful, erythematous joint with purulent material | Usually in large joints

Question 40

Most common causes of septic arthritis

Answer 40

S. aureus in children | N. gonorrhoeae in sexually active persons