Systemic Conenctions Flashcards
What was the major paradigm shift in microbiology?
Previous: “germs” - bacteria are pathogenic invaders
New: “Human-microbiome super-organism” - Microbes are essential and we are adapted to eachother
How are microbes beneficial?
Resistance against pathogens
Metabolic functions
Immune activatoin
How did the microbiology paradigm shift effect how we view bacteria?
Previously the goal was a sterile environment
Now, the goal is to manage and preserve native microbes (selectively rid of things)
How did the microbiology paradigm shift change our understanding of disease?
Old: Koch’s postulates and single-species acute diseases
New: Chronic diseases are caused by microbial community disruption and loss of healthy species
How did the microbiology paradigm shift change our direction for therapies?
Old: Therapies focused on broad eradication (antibiotics and antiseptics)
New: Therapies to encourage healthy communities (probiotics, prebiotics, targeted antimicrobials)
What are prebiotics?
Encourage growth of good bacteria
What are targeted antimicrobials?
Smart antibiotics that only target certain things
Theory of Focal infection
Idea that oral “focus of infection” causes systemic disease dates back at least to Hippocrates who reported the cure of arthritis after removal of a tooth
People used to thing fillings form America were causing bad things
New evidence is showing what?
Connections between oral infections and systemic diseases
What are the direct mechanisms for oral connections?
Translocation of bacteria
Translocation of toxin
Translocation of bacteria
Distant site infections are seeded by oral bacteria
Translocation of toxin
Distant site effect from toxin produced by oral bacteria
What is a major mechanism for immune system mediated oral-systemic condition connection?
Host hyper-inflammatory phenotype common pathway to disease
Example: IL-1 gene polumorphisms are associated with periodontitis and systemic diseases
What do epidemiologic studies show?
They show association
Don’t establish causation
What can Evidence of Causality entail?
Human trials showing oral diseases treatment prevents systemic disease or lowers systemic infections
Presence of oral bacteria at disease site
Demonstration of effect in animal model
Infective Endocarditis
Platelets and fibrin adhere to exposed CT producing nonbacterial thrombotic endocarditis (NBTE)
Bacterial from the oral cavity enter the blood stream and adhere to NBTE causing a clotq
Bacteria multiply, infiltrate the heart, and cause cardiac and valvular injury
Discharged into the circulation produces emboli and stroke
What are the major bacteria in Infective Endocarditis?
Oral streptococci 60+% (also A. actinomycetemocomitans and gemella) Skin bacteria (25%)
T/F - There is evidence that connects dental procedures with Infective Endocarditis
False
What is Antibiotic prohpylaxis? Can it prevent Infective Endocarditis?
Antibiotics are taken to (in theory) prevent spread of bacteria through bacteremia
In practice, it doesn’t really prevent bacteremia
It is unlikely to prevent many cases of IE
T/F - Random bacteremia form routine activities are more likely to cause IE than dental procedures
True
What is the most important factor in reducing the risk of Infective Endocarditis?
Optimize regular oral hygiene measures to keep bacterial load low
(Much more effective than antibiotic prophylaxis)
How did the paradigm shift effect the way we view antibiotic prophylaxis?
We shifted from using antibiotic prophylaxis to access to dental care and oral health
If a patient is high risk for Infective Endocarditis, and we are doing a very invasive procedure, we give a single high dose of amoxicillin right when we treat
What can cause “Aspiration Pneumonia”
Aspiration of oral secretions or oral bacteria
Aspiration pneumonia is common when airway protected reflexes are compromised (physically handicapped, elderly, very ill pts)
What can help prevent lung infections?
Oral hygiene measures
-reduce nosocomial pneumonia by 40%
-can prevent 10% of deaths in elderly nursing home
(strong evidence)
Preterm birth is connected with what? How?
Periodontitis
Bacteria in amniotic fluid associated with preterm births have some oral species
(not very strong evidence)
Why are immunosupressed patients high risk for disseminated strep or Candida of oral origin infection?
They don’t have a good immune system, so they can’t fight off normal oral microbiota if it gets somewhere it shouldn’t be
What should we consider when treating an immunocompromised patient?
Focus on achieving/maintaining good oral hygiene
Invasiveness of the procedure
Bacterial load
The degree of immunosuppression
Diabetes is connected with what oral disease? Why?
There is an increased prevalence of periodontitis in diabetics
Treatment of periodontitis improves glycemic control (something about periodontitis makes glyvemia harder to control)
-Evidence is strong, and the effect is moderate
What is the connection of Cardiovascular disease and oral bacteria?
Coronary heart disease, stroke, and peripheral vascular disease are all associated with periodontitis
There is a link, but causative relationship hasn’t been established
Could be bacterial toxins or bacteria itself, or because people with that phenotype are hyper-inflammatory
What is the evidence for causality between CVD and periodontitis?
Perio Tx trials show favorable responses on labratory markers but do not show reduction of CVD
P. gingivalis and other perio pathogens are found on atherosclerotic lesions
P. gingivalis exacerbates CVD in animal models
There are plausable biologic pathways
T/F - Studies show risk of pancreatic cancer in patients with periodontitis
True - we don’t know it there’s a common pathway, though
Cardiovascular Implantable Electronic Device (CIED) infections
Caused by bacteria from skin, hands of hospital workers, or environmental staph biofilms
Not oral species
Do not give antibiotic prophylaxis prior to dental treatment - hands are the issue
Patients with vascular grafts/stents
Most infections are caused by bacteria native to skin or bowels
Oral organisms are rarely infecitous
Do not give antibiotic prophylaxis prior to treatment
Patients with intravascular access devices
Wide variety of devices
Infections are usually caused by staph or other skin environment bacteria
Do not give antibiotic prophylaxis for any reason
Good infection control practices are key
Joint prostheses
1-2% become infected (high morbidity)
Most infections occur in perioperative period from wound contamination
Primary prophylaxis for patients with joint prosthesis
Evidence is strong for primary antibiotic prophylaxis at the time of device placement
Secondary prophylaxis for patients with joint prosthesis
Evidence is lacking for secondary prophylaxis to reduce dental procedure-related bacteremia and distant site infection
So prophylaxis for dental procedure is not generally recommended
Patients with bone pins, plates, and screws
Orthapedic hardware not within synovial joit is not at increased risk for hematogenous seeding by microorganisms
Infections are caused by staph or other skin bacteria
Not indicated for antibiotic prophylaxis prior to dental treatment
Patients with CSF shunts
Infections are caused by skin bacteria, not oral
Don’t need AP
Direct transfer of oral bacteria can cause what issues?
Infective Endocarditis
Pneumonia in compromised airway
Immunosuppression
Preterm birth?
What are the primary preventive strategies to prevent issues related to direct transfer of oral bacteria?
Improve oral health and reduce bacterial load
Antibiotic prophylaxis in specific high risk situaitons
Indirect transfer of oral bacteria or toxin, or common inflammatory pathways are related to what issues?
Type 2 diabetes
Cardiovascular disease
Pancreatic cancer
What is the primary preventive strategy to prevent issues related to oral bacteria or toxin transfer or common inflammatory pathways?
Treat periodontal disease to improve microbial profile
Improve overall health by addressing risk factors
T/F - Human microbiota is niche specific
True - and therefore they have limited range and limited ability to cause systemic disease
