1Bacteria have bi-phasic forms, what are their two forms?
Planktonic: Free floating
Sessile: Attached to a surface
2Biofilms are often started by planktonic bacteria, but they can also be started by:
Yeasts, like Candidas and Pseudomonas auriginosa
3Bacteria can "cross-talk" with other microbes in the biofilm colony, allowing them to organize for colony health and protection. This is facilitated by:
Quorum Sensing
4What is quorum sensing?
Bacteria use chemical signaling molecules to detect, communicate, and organize with other microbes.
5Microbes in a biofilm can be up to _______ more resistant to the host's immune system.
6What are the first 2 phases of the 4 phase Biofilm Life Cycle?
The Biofilm Life Cycle has 4 stages of growth:
• Attachment (Lag): Planktonic bacteria attaches to a surface and begins to modify its genes to the biofilm phenotype. Bacterial growth lags.
• Log: Bacteria becomes sessile, the anchoring makes it more resistant to the immune system. Cohabitants are recruited.
7What are the last 2 phases of the 4 phase biofilm life cycle?
• Stationary: Bacteria produces peak biofilm matrix, the colony rapidly grows until it plateaus as its stable climax community.
• Death: The biofilm stops growing and begins to fragment. Sloughed off pieces anchor to new areas in the body and start to grow.
8What are the 4 reserviors of biofilm colonizers in the body?
Gastroinstinal > Genitourinary > Integumentary > Oral
Gastrointestinal reservior is the most dangerous and potent
9What is the most common biofilm colonizer of Indwelling Medical Devices in general?
- Candida yeasts
- Giardia
- Staphylococci
- Streptococci
10Biofilms are present in ___ of all HAIs
11Once attached to host tissue, plaktonic bacteria become sessile and shift to the biofilm phenotype. This allows it to do two things to form the biofilm colony:
1. Quorum sensing
2. Secrete biofilm matrix
12How do biofilms get most of their nutrients?
The bacteria inflames (but does not destroy) the underlying host tissue. The inflammation causes nearby capillaries to begin leaking plasma, which the biofilm can feed on.
13Biofilms lose most of their nutrients through
- Their top region, which faces the inner lumen
- Their innermost region, that is anchored to the host endothelium
- Their anoxic region
14What is the threshold called where a biofilm achieves enough numbers to have a stable colony?
The Climax Colony
15What are the three major biofilm causing bacteria in periodontal/subgingival biofilm infections?
- Porphyromonas g.
- Streptococcus a.
- Bacteriodes f.
- Treponema d.
- Lactobactillus g.
16Periodontal bacteriaa like to reside in enamel, subgingival pocket, and in floxes. What are floxes?
Free-floating microbial colonies
17What are the two most common colonizers in Heart Valve Biofilms (Endocarditis)?
Streptococci and staphylococci
18How do planktonic bacteria attach to the walls of heart valves with all of that shear fluid pressure?
By producing special adhesion factors called Extracellular Polymeric Substances (EPS)
19What are the 2 primary biofilm colonizers of pediatric CF patients?
- H influenzae
- Pseudomonas auriginosa
- Candidas
- Staphylococcus aereus
20What is the primary biofilm colonizer in adolescent (and older) CF patients?
- Staphyloccocus a.
- Candidas yeasts
- Pseudomonas auriginosa
- H. influenzae
21Why do biofilms in IMDs grow optimally intraluminally?
Within the lumen, the biofilm is more protected from the hosts internal environment, and the shear fluid dynamics within help the colonizers move through the IMD and the body itself.
22Critically Colonized open wounds have:
- More biofilm microbes than normal flora
- Surface level infection that has not broken into the deeper body tissues
- A foamy appearance, with more exudate, and potential odor
- caused a strong internal immune response
23PCR testing can only indirecty identify biofilms because
Biofilms are polymicrobial communities, and PCR testing can only detect the presence of one kind of microbe at a time.
24What is the preferred method of sequencing microbes in biofilms?
Pyrosequencing
25Blood samples collected for cultures and screens for biofilms must be less than ____ old.
24 hours
26The establishment of ______ is the preferred way to prevent biofilm infections
Catheter care teams, which use implement multiple preventative modalities (called a bundled approach) to monitor and mitigate biofilm growth.