Chapter 47 Osteomyelitis and Implant-Associated Infections

Question 1

Define glycocalyx

Answer 1

Bacteria produced exopolysaccharides (bacterial slime).

Question 2

How does a glycocalyx form and what is its purpose

Answer 2

Bacteria reproduce inside the glycocalyx matrix and form colonies
Colonies coalesce to form biofilm

Effect: Assist bacterial cells to firmly attach itself to the implant or tissue site

Question 3

Define passive layer

Answer 3

forms on the surface of stainless-steel implants protecting implant from corrosion.

Question 4

Passive layer vs conditioning layer

Answer 4

Passive layer focuses on preventing negative interactions while conditioning layer actively aims to promote positive biological responses.
Passive layer: protective layer on the implant used to prevent corrosion
Conditioning layer: layer of adsorbed macromolecules from the local tissue environment.

Question 5

What are the three parts of a biofilm

Answer 5

Offending microbe
Microbe-produced glycocalyx
Host biomaterial surface or conditioning layer

Question 6

Describe conditioning layer of a biofilm on an implant

Answer 6

Layer consists of proteins and polysaccharide molecules.
Fibronectin within the conditioning film and bacterial adhesins allow for bacterial adhesion.

Question 7

Which antibiotic is distributed to bone to bind to calcium

Answer 7

Tetracyclines and potentially fluoroquinolones