Wound Bench

Question 1

Ideal way to collect a specimen from a wound

Answer 1

Asperate

Question 2

Ideal way to transport a wound specimen to the lab

Answer 2

As soon as possible in specific transport media

Question 3

Delay shorter than 6 hours

Answer 3

kept at ambient temperature

Question 4

Delay longer than 6 hours

Answer 4

refrigerated

Question 5

What is specimen collection is preferred?

Answer 5

Specimens aspirated with a needle and syringe are preferred to those collected on swabs

Question 6

Common submitted specimen

Answer 6

1. Sterile body fluids
2. Biopsy/Tissue
3. Eye
4. Ear
5. Foreign body
6. Catheter tips
7. Wounds

Question 7

What media should be inoculated from a wound?

Answer 7

1. BAP
2. CHOC
3. MAC
4. CNA
5. ANA BAP
6. PEA
7. THIO
8. Direct Smear

Question 8

Purpose of BAP

Answer 8

All purpose medium, best for hemolysis, detects stalemating of Haemophilus around organisms such as Staphylococcus aureus

Question 9

Purpose of MAC

Answer 9

Selective for Gram negative rods, (look for Lactose pink). (does not determine fermenter or non fermenter of glucose)

Question 10

Purpose of CNA

Answer 10

Selective for Gram positive organism (do not determine hemolysis)

Question 11

Purpose of CHOC

Answer 11

Enriched medium that will grow most any organism (supports fastidious organisms)

Question 12

Purpose of ANA BAP

Answer 12

Prereduced, growth supplements added (enriched with Vitamin K. Hemin and cysteine)

Question 13

Purpose of PEA

Answer 13

Phenyl Ethyl Alcohol Agar

Inhibits swarming of proteus

Question 14

Purpose of THIO

Answer 14

Enhances growth of aerobes, facultative organisms, as well as obligate anaerobes

Question 15

Purpose of direct smear

Answer 15

Very important to correlate with plate morphology

Question 16

How does gas gangrene (myonecrosis) present on a gram stained direct smear from an infected wound

Answer 16

Necrotic background and gas bubbles

Question 17

How long are anaerobic plates typically incubated before initial examinations?

Answer 17

2 days (48 hours)

Question 18

How is quantitation determined for wound cultures

Answer 18

Quantitation is dependent on the quadrant where organisms are growing (1+ first quadrant; 2+ second quad, 3+ third quad, 4+ fourth quadrant)

Question 19

What skin flora organisms would likely be seen in surface wound cultures

Answer 19

• Alpha and Gamma Strep
• Corynebacterium spp
• Coag Neg staph
• Propionibacterium spp.
• Staphylococcus saccharyolyticus
• staphylococcus epidermidis

Question 20

Biochemical Tests Used to Identify:

- Coag Neg Staph

Answer 20

Gram Stain: GPC in clusters

Coagulase test: neg

Question 21

Biochemical Tests Used to Identify:

- Corynebacterium spp

Answer 21

Gram Stain: GPR palisading
Catalase: pos
Nonmotile
opaque and or alpha

Question 22

Biochemical Tests Used to Identify:

- Strep Viridian’s (alpha or gamma strep; not group D)

Answer 22

Gram Stain: GPC in chain

Question 23

Biochemical Tests Used to Identify:

- Propionibacterium spp.

Answer 23

Anaerobe

Question 24

Most common organism in burns

Answer 24

Pseudomonas aeruginosa
MRSA
Enterococcus
Klebsiella

Question 25

Conventional biochemical tests (and reactions) that would be used to identify the organisms that are in burns

Answer 25

Pseudomonas aeruginosa is Oxidase Positive

Question 26

Most common organism causing Impetigo, Erysipelas, Cullulitus, Folliculitis, Furuncle, Carbuncle, etc.

Answer 26

Staph aureus

Question 27

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause Impetigo, Erysipelas, Cullulitus, Folliculitis, Furuncle, Carbuncle, etc.

Answer 27

S. aureus: - Cat + - Coagulase + - Beta hemolytic - Furazolidone Susceptible - Novobiocin Susceptible

Question 28

Most common organism causing dog/cat bite infections

Answer 28

Pasteurella multocida/ canis, bacteroides spp., Fusobacterium, Prevotella, staph, capnocytopaga canimorsus

Question 29

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause dog/cat bite infections

Answer 29

GNCB - nonmotile - facultatively anaerobic - form nitrites from nitrates - ox pos - cat pos

Question 30

Most common organism causing human bite infection

Answer 30

Eikenella corrodens, | Straptococcus anginosis, S. aureus, Fusobacterium nucleatum, prevotella melaninogenica

Question 31

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause human bite infection

Answer 31

``` E. corrodens GNCB nonmotile ox pos asaccharolytic cat neg "pit" smell like chlorine ```

Question 32

Most common organism causing surgical wound (head neck) infection

Answer 32

``` Mouth Flora anaerobes: Anaerobe: Prevotella spp. Alpha and gamma streptococci Corynebacerium spp CoN Staph Non-Pathogenic Neisseria spp Porphyromonas spp. ```

Question 33

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause surgical wound (head neck) infection

Answer 33

*

Question 34

Most common organism causing surgical abdominal wound infections

Answer 34

``` GI flora: Bacteroides frag Clostridium Bifidobacterium anaerobic cocci Fusobacterium E. coli (other Enterobacteriaceae) Enterocuccus ```

Question 35

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause surgical abdominal wound infections

Answer 35

*

Question 36

Most common organism causing Myonecrosis (gangrene)

Answer 36

``` Clostridium perfringens (most common) - C. histolyticum, C. septicum, C. novyi ```

Question 37

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause Myonecrosis (gangrene)

Answer 37

GPR - double zone beta hemolysis - 4+ gas

Question 38

Most common organism causing Necrotizing fasciitis

Answer 38

``` Enterobacteriaceae and anaerobes (type 1) S. pyogenes (type 2) Clostridium perfringens (type 3 or Gas gangrene) ```

Question 39

Conventional biochemical tests (and reactions) that would be used to identify the organisms that cause necrotizing fasciitis

Answer 39

KIA series / anaerobe tests (GLC) / strep test