Reviewing Material slides Exam 2 Flashcards
Most odontogenic infection have why type of flora?
70 % have mixed flora (aerobic and anaerobic)
- 25% have pure anaerobic
- 5% have pure aerobic (rare)
What is characteristic of Early infections
Aerobic streptococci
- Sensitive to penicillin
- Anaerobes appear around 3 days after onset of symptoms
What is characteristic of Late infections
Anaerobes
- Frequently resistant to penicillins
What is the drug of choice to treat mild or early odontogenic infections
Penicillin VK
If patient is penicillin allergic, what is drug of choice to treat mild or early odontogenic infections? Secondary alternative
Clindamycin
Secondary alternative: first generation cephalosporins
-*however not good against anaerobes
Describe spectrum of kill for Penicillin VK and bacteria it is effective against
Bactericidal
- against gram-positive cocci and major pathogens of mixed anaerobic infections
Narrow spectrum
When should one take penicillin VK
Take 1 hour before or 2 hours after meals
- maximizes serum levels
Adverse reactions of Penicillin VK
Nausea, mild diarrhea, oral candidiasis
T or F, Amoxicillin is better than penicillin VK for treatment of odontogenic infections
False, there is no advantage over penicillin VK
- Less effective than penicillin VK for aerobic gram-positive cocci; similar against anaerobes
What is amoxicillin good against?
H. influenzae
- acute sinus and otitis media infections
Is the effect of Clindamycin dose dependent?
Yes, static (low dose) and cidal (high dose)
Adverse effects of clindamycin
Primarily GI
Hypersensitivity reactions are rare
Spectrum of kill for clindamycin
Broad spectrum
can be static or tidal depending on dose
- Resistant to beta-lactamase degradation
What is the drug of choice for late odontogenic infections
Clindamycin
Could penicillin still be considered for late odontogenic infections?
Yes, resistance rate is between 35-50%
- If patient is not responding to penicillin after 36 hours, then assume resistant pathogen is present
- Could also add metronidazole to expand spectrum of kill of penicillin
First generation Cephalosporins are most active against what bacteria
Gram-positive cocci
- Not very good against many anaerobes
Adverse event of first generation cephalosporins
Diarrhea (10% of users)
T or F, patients who are intolerant to penicillins may be intolerant to cephalosporins
True
If patients have full blown Type I (IgE) mediated allergic reaction is cephalosporin indicated?
No, it is contraindicated, up to 20% of these patients will be cross-sensitive
Resistant anaerobes in odontogenic infections
- Prevotella
- Porphyromonas
- Fusobacterium nucleatum
- Campylobacter gracilis
- Fusobacterium + S. viridans = often seen in severe odontogenic infections.
* -Typically resistant to macrocodes, use clindamycin or amoxicillin/clavulante (Augmentin)
Beta-lactamase resistant penicillins
Methicillin Oxacillin Cloxacillin Dicloxacillin Nafcillin
What are beta-lactamase resistant penicillins effective against?
Only effective against gram-positive cocci
No activity against anaerobes
Not indicated for late stage odontogenic infections
Metronidazole is good for what?
Aggressive periodontal infections
- Do NOT use for chronic periodontitis
Erythromycin indications:
No longer effective against oral organisms due to resistance or used in dentistry
-**formerly alternate drug of choice for orofacial infections for patients who were allergic to penicillins
