Exam 4 - 30-32. Antibiotic Usage and Antibiotic Resistance Flashcards
2
What is the definition of antibiotic resistance?
3
What kind of target organisms do antibacterials have? What effect does this have on toxicity?
3
What are the target organisms of antifungals?
3
What are the target organisms of antivirals
3
What happens to cytotoxicity when using antifungals and antivirals?
4
What are the six leading pathogens associated with antibiotic resistance?
5
One Health emphasizes the health linkages among what three things?
8
What was the most prescribed antibiotic in 2021? 2nd most?
11
What percent of antibiotics prescribed for infection prophylaxis before dental visits were unncecessary?
13
What are 6 groups tha tmay need modified medical care when it comes to antibiotics?
14
What are two outcomes of resistance going undetected?
15
What is the annual cost for 6 of the 18 most alarming antibiotic resistance threats?
15
What are the 6 most alarming antibiotic resistance threats?
17
_____ and _______ organismsm are found in the sink drains of dental offices.
17
_______ isolates from dental unit waterlines can be divided in two distinct groups, including one displaying phenotypes similar to isolates from cystic fibrosis patients.
20
The ADA’s evidence-based approach has resulted in decreased recommended prophylactic use of antibiotics in ______, as well as people who have had ______.
20
Compared with previous recommendations, there are currently _______ for whom antibiotic prophylaxis may be indicated prior to certain dental procedures.
22
What does the ADA support the prudent use of antibiotics for?
22
Antibiotic prophylaxis prior to dental procedures is reserved for patients at high risk of _________.
23
What organism does this describe?
Gram positive, anaerobic, motile rod-shaped bacterium with the ability to form spores
23
Antibiotic use has been associated with the presence of C. dif and GI system disease known as ______.
23
What are three antibiotics that are associated with higher risk of C. dif infection?
24
What are four risks of C. dif disease?
24
What is the primary treatment for dental C. diff infection?
31
Instead of prescribing antibiotics, dentists should prioritize dental treatments such as:
- _____
- _____
- ______
- __________
- ______
33
Can patients with prosthetic joints that have a history of complications who are undergoing gingival manipulation by considered for prophylactic antibiotics?
35
What are 5 diseases that patients who took prophylactic antibiotics in the past but not longer need them include?
36
What are the three primary portals for bacterial endocarditis?
36
______ and _____ organisms are responsible for more than 80% of bacterial endocarditis?
38
Can these patients have prophylaxis antibiotics?
1) Prosthetic cardiac valve or prosthetic material used for cardiac valve repaired
2) Previous infective endocarditis
3) Congenital heart disease (CHD)
4) Unrepaired cyanotic CHD, including palliative shunts and conduits
5) Completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first six months after the procedure
6) Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization)
7) Cardiac transplantation with regurgitation due to a structurally abnormal valve
39
What are four things that prophylaxis is needed for?
40
What are three indications for systemically administered antibiotics?
43
When is antibiotic prophylaxis done before a procedure?
43
If a patient forgets to take their priphy
43
Is a follow-up dose of antibiotics recommended after a procedure?
49
What are two characteristics of gram-positive bacteria?
49
What is a key feature of gram-negative bacteria?
51
What does this describe?
Complex theory” where periodontal pathogens are categorized based on their association with the severity of disease
56
What are the two drugs of choice for oral therapy?
57
What doe Procaine do?
58
Pencillin G and V have a wide spectrum, including ________ bacteria, except for producers of ______.
58
What bacteria is Penicillin G and V moderate against?
58
What is penicillin G and V inactive against?
59
What anaerobic mouth flora is penicillin G and V used for?
59
______ may have predictive value for diagnosis of oral squamous cell carcinoma.
59
50% of Prevotella produce a _______.
59
_______ is active against virtually all mouth and respiratory tract Bacteroides and Prevotella isolates and is recommended by some experts as the drug of choice for anaerobic infections of the oral cavity. BUT NO LONGER RECOMMENDED!!
60
What are two antibiotics that should be considered first if you have to use antibiotics? When would you consider not using these drugs?
61
What do B-lactam antibiotics inhibit?
61
B-lactam antibiotics bind to ________.
61
_______ are cytoplasmic membrane enzymes responsible for peptidoglycan synthesis.
64
What type of antibiotics are these:
methicillin, nafcillin, oxacillin, cloxacillin, dicloxacillin
64
What is the spectrum of bacteria that B-lactamase resistant Penicillins can be used for?
64
What are three exceptions for B-lactamas-resistant penicillins?
65
What are the two aminopenicillins?
65
What are aminopenicillins better for?
65
Are ampicillin are amoxicillin taken by mouth or IV?
65
_____ has better oral bioavailability and is less likely to select antibiotic resistance in intestinal flora.
66
What are aminopenicillins inactivated by?
66
Which anaerobe is resistant to aminopenicillins?
67
What are two examples of expanded spectrum pencillins?
67
What does this describe?
-Expanded Gram-negative spectrum including Pseudomonas
- Less potent, inactivated by β-lactamases, more expensive
- Parenteral (IV)
- For serious infections in hospitalized patients, often in
combination with an aminoglycoside
- Generally not to be used if pathogen is susceptible to older penicillins or 1st generation cephalosporin
70
What is the main adverse effect of penicillins?
70
What do these describe?
- CNS toxicity (seizures) with extraordinarily high
doses or direct application of drug onto neuron
- Hematologic (neutropenia, bleeding)
- Hepatic (elevated transaminase)
71
Do most patients who think they have a penicillin or cephalosporin allergy actually have one?
71
A pencillin skin test will test negative in ____ of oatients.
72
What does this describe?
- Alternatives to penicillins
- Drugs of 2nd choice, not 1st choice
- Two side chains (penicillins only have one): potential for many analogs
- Lots of options
73
What is the preferred Cephem drug for prophylaxis?
73
Cephems can interfere with ____. they can also prevent _____
73
Cefaclor has a high incident rate of what?
74
Carbapenems are very potent against _______.
74
Carbapenems are active against:
- _____
- _____
- ______
75
What is the best cabapenem for dentistry?
75
_____ are the drugs of last resort for dentistry.
75
Do not use carbapenems if patient is allergic to _____.
78
What drug does this describe?
siderophore (iron chelator) enters through iron
transporter but target is still PBP
79
What are four antibiotic resistance mechanisms?
80
What does pan-resistant mean?
82
What is the main mechanism of resistance in the oral cavity?
82
These are all examples of what?
Bacteroides
Veillonell
Haemophilus
Eikenella
Capnocytophaga
Streptococcus
Prevotella (adult periodontitis), pediatric and adult CF patients
83
What are the four classes of B-lactamases?
86
What does overproduction of efflux pumps lead to?
88
What is Vancomycin?
99
What is the spectrum for glycopeptides?
89
What antibiotic does this describe?
- ## Nephrotoxic, ototoxic*Redneck or red man syndrome
*Due to histamine release
*SLOW IV infusion to reduce histamine release
*Sometimes cardiac effects, ototoxicity *Also – skin rashes, phlebitis, neutropenia
90
Resistance to Vancomycin emerged in _____ and reduced susceptbility emerged in _____.
94
What is Telavancin?
94
What does Telavancin inhibit? What does it disrupt?
95
Sulfonamides mimic and compete with _____, blocking _______.
95
Trimethoprim blocks reduction of __________.
95
When used together, sulfonamides and trimethoprim have a ______ activity. They result in ________.
97
Sulfonamides are mostly used for _____ and often for ______ infections.
97
Are sulfonamides relevant to dentistry?
97
Trimethoprim is used for ______ and often effective for ____ infections.
98
Daptomycin is only used against ______ agents.
98
Polymyxins are only used against ______.
99
Daptomycin is active against ____ and _____.
100
What is the mechanism of action for Daptomycin?
101
What do these describe?
Rapidly bactericidal irrespective of phase of growth
Nephrotoxic and neurotoxic
Last-last resort options for
infections by Acinetobacter, P. aeruginosa, multi-resistant Enterobacteriaceae
Resistance now emerging
Also used topically - alone and in Neosporin
106
What does this describe?
Potential antiplaque agent Very effective
Two major drawbacks:
Bad taste and Stains teeth
107
What do fluoroquinolones interfere with?
107
Why are fluoroquinolones inapprorpriate for kids?
108
What does this describe?
Regulate conformational changes in DNA topology by catalyzing the breakage and rejoining of DNA strands during normal cellular growth
108
What does this describe?
-Adds negative supercoils
-Removes positive supercoils
108
What does this describe?
-Removes positive supercoils
- Decatenates daughter chromosomes, plasmids
114
What is Rifampin active against?
114
What is the target of Rifampin?
114
What are three things that Rifampin is used for?
115
What are four anti-mycobacterials?
115
How many antibiotics do you need to treat TB?
116
What are two things that Metronidazole and Tinidazole treat?
116
____ is an alternative to vancomycin for C. dif.
118
What are two mechansism of action for aminoglycosides?
118
What is the only protein synthesis inhibitor that is cidal?
121
What does this describe?
Usually oral therapy
Broad spectrum
Active vs Mycoplasma, Rickettsia, Chlamydia
Rx syphilis in pen-allergic pts
122
What is a short accting tetracycline example?
122
What are two long acting tetracycline examples?
123
What are two problems with Tetracyclines?
125
What are Erythromycin, Clarithromycin, and Azithromycin all examples of?
125
What does this describe?
Rx - streptococcal respiratory infections in penicillin-allergic patients; also Mycoplasma, Legionella, less severe staphylococcal infections
Generally safe and well tolerated
125
What is the drug of second choice to penicllin for most uses in dentistry?
126
Inhibition of protein synthesis occurs via binding to the ___ ribosomal RNA.
126
Which macrolides does this describe?
Newer, more expensive
Better pharmacologically Active vs H. influenzae
Less gastric disturbances
127
What does this describe?
Macrocyclic (macrolide) antibiotic
Bactericidal against C. difficile
inhibits RNA polymerase from
binding to the promoter
127
What does this describe?
more active in vitro than vancomycin against clinical isolates of C. difficile,
minimal systemic absorption
high fecal concentrations
limited activity in vitro and in vivo against components of the normal gut
Can provide highly active but
more selective therapy for C. difficile infection.
128
What are lincosamides a common cause of?
128
Are lincosamides an alternative for erythromycin?
129
What does this describe?
Lipid soluble - penetrates CSF & humors of eye – Rx meningitis due to H. influenzae, S. pneumoniae, N. meningitidis if penicillin allergy
Also for serious infections due to Salmonella typhi & Bacteroides fragilis
Antagonizes bactericidal drugs
129
Chloramphenicol may cause _____ abnormalities.
130
What is a fatal adverse reaction of chloramphenicol?
130
What is the syndrome in babies caused by chloramphenicol?
130
Should chlroamphenicol ever be used in dentistry?
132
What does this describe?
(IV) - derived from minocycline Trade name = Tygacil
Active against many pathogens MRSA
VRE
Acinetobacter
Enterobacteriaceae (multidrug-resistant)
Weak activity vs P. aeruginosa & Proteus
133
What are Ketolides?
133
What is an example of a Keetolide?
133
Telithromycin is approved only for ________.
134
What does this describe?
Quinupristin-dalfopristin (IV)
- Trade name = Synercid
- combination of streptogramin A and B
gives synergistic ribosomal binding
- Active vs vancomycin-resistant Enterococcus faecium, MRSA
135
What does this describe?
Linezolid (PO, IV)
- Trade name = Zyvox
- Active vs ALL clinically relevant gram-positive cocci (VRE, MRSA)
- Skin & soft tissue infections, pneumonia
- Wider spectrum, oral availability, fewer side affects – often preferred to quinupristin-dalfopristin (Synercid)
141
When are multiple antibiotics superior to a single antibiotic?
141
When are bactericidsal drugs superior to bacteriostatic? When is the opposite true?
141
Do bacterial infections require a “complete course” of antibiotics?
142-143
What can be done to avoid hospital-acquired pneumonia in terms of dental treatment?
