Skin & Soft Tissue Infections

Question 1

how can skin and soft tissue infections be classified?

Answer 1

• by microbe

- by anatomy

Question 2

what are the different types of microbial groups that can cause skin and soft tissue infections?

Answer 2

• bacteria
• viruses
• fungi

Question 3

what type of microbe is S. aureus?

Answer 3

gram positive cocci bacteria

Question 4

what is a virulence factor of S. aureus?

Answer 4

Payton Valentine Leukocidin toxin (kills white cells)

Question 5

what is meant by a ‘cocci’ bacteria?

Answer 5

round shaped bacterium

Question 6

are S. aureus normally seen in chains or clumps?

Answer 6

clumps

Question 7

what disease can occur as a result of infection with S. aureus?

Answer 7

Angular cheilitis (inflammation of angles of the mouth)

Question 8

what are the different types of S. aureus microbes? what do the

Answer 8

• Methicillin SENSITIVE

- Methicillin RESISTANT

Question 9

the clones of which division of S. aureus produces community acquired MRSA?

Answer 9

Methicillin resistant S. Aureus

Question 10

what is Panton-Valentine Leucocidin?

Answer 10

bacterial exotoxin

Question 11

what occurs if a patient is infected with Payton-Valentine Leucocidin positive S. aureus?

Answer 11

• S. aureus produces PVL subunits
• PVL sub-units form pores
• pores attach themselves to a leukocyte
• causes the cell to release inflammatory mediators

Question 12

what is a clinical effect of PVL positive S. aureus?

Answer 12

• necrotising pneumonia

- recurrent skin infections

Question 13

what type of microbe is S. pyogenes?

Answer 13

gram positive cocci bacteria CHAINS

Question 14

what is a virulence factor of S. pyogenes?

Answer 14

• superantigens

- toxic shock syndrome

Question 15

what is the function of superantigens?

Answer 15

they cause a huge disregulation of the immune response

Question 16

how does toxic shock syndrome occur?

Answer 16

• S. pyogenes releases superantigens
• superantigens attack T lymphocytes
• T lymphocytes release cytokines
• stimulates TSS

Question 17

what bacteria is responsible for cellulitis?

Answer 17

S. pyogenes

Question 18

what classification of microbe does S. anginosus fall under?

Answer 18

gram positive cocci bacteria (chains or clump)

Question 19

what is a virulence factor of the S. anginosus group?

Answer 19

intermedilysin (cytotoxin that causes lysis of cells)

Question 20

what type of microbe are anaerobes?

Answer 20

gram positive rod-shaped bacteria that live and grow without oxygen

Question 21

what type of microbe is Clostridium Welchii?

Answer 21

an anaerobe

Question 22

what is a virulence factor of C. Welchii?

Answer 22

alpha toxin (lecithinase)
- lecithin is a fatty acid found in our cell membranes, this virulence factor is very potent at breaking down cell membranes

Question 23

what type of reaction is used to detect alpha toxin & help confirm identity of C. welchii?

Answer 23

The Nagler reaction

Question 24

what disease can occur as a result of anaerobes?

Answer 24

gas gangrene (clostridial myonecrosis)

Question 25

what type of microbe does the Herpes simplex group fall under?

Answer 25

virus

Question 26

what is a virulence factor of the herpes simplex virus?

Answer 26

cell lysis

Question 27

what classification of microbe does Candida Alibicans fall under?

Answer 27

fungi

Question 28

what is a virulence factor of Candida Albicans?

Answer 28

phospholipase (breaks down phospholipids in our cells)

Question 29

where is Candida Albicans most commonly seen orally?

Answer 29

On the hard palate as a result of denture stomatitis

Question 30

what are the different types of anatomical groups that skin and soft tissue diseases can be classified under?

Answer 30

• superficial

- deeper tissues

Question 31

what is a disease of the epidermis?

Answer 31

• impetigo & angular cheilitis