Infection of Skin, Soft Tissue, Muscle, and Associated Systems Flashcards Preview

IMSK Exam 2 > Infection of Skin, Soft Tissue, Muscle, and Associated Systems > Flashcards

Flashcards in Infection of Skin, Soft Tissue, Muscle, and Associated Systems Deck (19):
1

Most common skin flora

Staphylococcus epidermidis

2

What are Langerhans cells?

Dendritic cells in the epidermis

3

Is S. epidermidis gram positive or negative? Catalase positive or negative?

Gram positive
Catalase positive

4

What is toxemia?

Bacterial infections release skin-damaging toxins through the blood

5

What is a macule?

Flat, red: Local inflammation immune response infiltrating leukocytes

6

What is a papule?

Raised, red: More marked inflammation (invasion of neighbouring tissue)

7

What is a vesicle?

Small blister (pus): Microbes invades epithelium (HSV, VZV)

8

What is an ulcer?

Epithelium ruptures, microbe discharged

9

What is a papilloma?

Microbe grows in epithelium which proliferates; microbes shed with epithelial cells (wart)

10

What is the difference between petechiae and purpura?

Petechiae is smaller skin bleeding
Purpura is larger skin bleeding

11

What are the properties of Staphylococcus aureus?

Gram positive
Beta-hemolysis
Gold colonies
Catalase positive
Coagulase positive

12

What does hemolysin do?

Lyses red blood cells

13

What is the difference between beta and alpha hemolysis?

Beta: complete destruction of the cell
Alpha: only partial destruction of the cells

14

What is a furuncle and a carbuncle?

Furuncle is a boil or deep folliculitis
Carbuncle is large fusion of many furuncles

15

What does staphylococcal exfoliative toxin (exfoliatin) do?

Digests cadherins in desmosomes causing the skin just below stratum granulosum to split

16

What does TSST cause?

Dilation of blood vessels, necrosis, diffuse erythematous rash

17

How does S. aureus acquire resistance to penicillin?

Production of Beta lactamase

18

How is methicillin resistance acquired?

Penicillin binding protein encoded by SCCmec

19

What are the properties of S. pyrogenes?

Gram positive
Small colonies