Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

pharmacology unit 6 > antimicrobial beta lactams > Flashcards

antimicrobial beta lactams Flashcards

1
Q

what essential for the function of beta-lactams

A

the beta-lactam ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what does the side chain of the beta-lactam determine?

A

the antibacterial spectrum and pharmacological properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what do beta-lactams bind

A

penicillin binding proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what do penicillin binding proteins do?

A

catalyze the polymerization of the glycan strand (transglycosylation) and the cross-linking between the glycan chains (transpeptidation).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what explains the differences in microbial spectrum?

A

the affinity of the PBP for the beta-lactam.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

are beta-lactamases PBP? what are they?

A

yes. they are the enzymes responsible for the enzymatic destruction of beta-lactams.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how do the beta-lactam actually cause bacterial death?

A

they cause a build up of peptidoglycan precursors within the bacteria and this initiates autolysins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

where does gram + produce beta-lactamase

A

outside the cell. preemptively stopping the activity of the beta-lactam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

where do gram - express beta-lactamase

A

located in the periplasmic space. they allow the beta-lactam into the space and then disable it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

is beta-lactamase a major cause of resistance in gram negative bacteria?

A

yes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are two other ways of gram negative beta-lactam resistance

A

alteration of the porins on the surface dont allow the passage of the antibiotic and alterations of PBPs (MRSA and strep. pneumoniae)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the natural penicillins

A

G and V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the three penicillin-resistant penicillins

A

oxacillin, nafcillin, dicloxacillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is another name for the penicillin-resistant penicillins

A

antistaphylococcal penicillins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the two aminopenicillins

A

ampicillin and amoxicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the two carboxy penicillins

A

carbenicillin and tricarcillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

name the ureidopenicillin

A

piperacillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

name the types of the beta-lactam

A

natural, antistaphylococcal, aminopenicillin, carboxypenicillin, ureidopenicillin, cephalosporins, carbapenems, monobactems.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

is there a different mechanism for the different types of beta-lactam

A

no. the same. preventing the transpeptidation (cross-linking) of peptidoglycan layers in the cell wall by binding to PBP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the half lives of the beta-lactam

A

short. 20 minutes. this is why they are given so frequently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

how are most of the beta-lactams eliminated

A

through the renal route, must take into account renal insufficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the most common SE of the beta-lactam

A

GI and HSR. acute interstitial nephritis and drug fever. hives and rash.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the downfall for the beta-lactam

A

they lack activity against organisms without a cell wall, such as mycoplasma and chlamydia pneumonia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

do the beta-lactam have MRSA activity?

A

no. except for ceftaroline.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is the antimicrobial spectrum for the natural penicillins

A

non-beta-lactamase producing gram +. streptococci. anaerobes (actinomyces, clostridium, prevotella, peptostreptococcus), select-gram (-) (neisseria), and syphilis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are the clinical uses for natural penicillins

A

streptococcal infections such as pharyngitis, cellulitis, endocarditis (viridans), and syphilis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what are the adverse effects of the natural penicillins

A

HSR, seizures at high dose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is the pharmacodynamics of the natural penicillins

A

ADE -penicillin V is a more stable acid the G. there is wide distribution, and there is renal elimination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

antistreptococcal agents

A

oxacillin, nafcillin, dicloxacillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the antimicrobial spectrum for the antistreptococcal

A

MSSA and strep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

clinical uses of antistreptococcal

A

primarily for MSSA. it is actually superior to vancomycin for MSSA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what to watch out for on antistreptococcal

A

penicillin HSR!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is the adverse effects for oxacillin

A

hepatotoxicity and neutropenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are the adverse effects for nafcillin

A

hepatotoxic and neutropenic and thrombocytopenic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

do you take dicloxacillin with food?

A

no it decreases its availability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

how are the antistreptococcal eliminated

A

hepatically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

how does the antistreptococcal evade the bacterial resistance

A

they have a bulky side chain that sterically shields the beta-lactam ring. However it also prevents entry into the gram negatives so they are useless there.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are the two aminopenicillins

A

amoxicillin and ampicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is special about the aminopenicillins

A

the aminogroup aids in the hydrophobicity so that it penetrates the gram (-) cell wall. used against oral anaerobes as well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what is the spectrum for the aminopenicillins

A

gram (+) (enterococcus, streptococci, and listeria). gram (-) hemophilus and E. coli.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

are the aminopenicillins good at killing gram negatives

A

not particularly because of resistance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are the clinical uses of the aminopenicillins

A

otitis media, URTIs, UTIs, endocarditis, listeria meningitis

43
Q

what are the aminopenicillins the drug of choice for?

A

enterococci

44
Q

what are the adverse effects for the aminopenicillins

A

HSR, rash and GI

45
Q

which of the aminopenicillins has better absorption

A

amoxicillin

46
Q

how do we use piperacillin and ticarcillin in clinical practice

A

with a beta-lactamase inhibitor. use them against staph, gram (-) rods, some anaerobes. they are not used often and when they are it is in combination with inhibitor.

47
Q

what is unasyn

A

ampicillin and sulbactam inhibitor combination.

48
Q

what is augmentin

A

amoxicillin and clavulanate inhibitor combination

49
Q

what is zosyn

A

piperacillin and tazobactam inhibitor combination

50
Q

what is timentin

A

ticarcillin and clavulanate inhibitor combination

51
Q

what are the only inhibitor combinations active against pseudomonas

A

pip/taz and tic/clav

52
Q

what bugs to the inhibitor combinations have poor activity

A

MRSA, extended spectrum beta-lactamase GNRs (e coli).

53
Q

what are the clinical uses of the inhibitor combinations

A

mixed infections, intraabdominal, diabetic foot-ulcerations, nosocomial pneumonia and aspiration pneumonia

54
Q

what are the adverse events for inhibitor combinations

A

HSR.

55
Q

what are the rare side effects for pip/taz

A

immune mediated thrombocytopenia, aplastic anemia.

56
Q

are the cephalosporins more resistant to lactamases than beta-lactam?

A

yes. they are also resistant to penicillinases but susceptible to cephalosporinases

57
Q

are cephalosporins active against MRSA, b. fragalis and enterococcus

A

no. with one exception: ceftaroline 5th gen. none work against fragilis.

58
Q

what are the adverse effects of the cephalosporins

A

HSR similar to the penicillins -they have cross-allergenicitiy

59
Q

what are the 1st generation cephalosporins

A

cefazolin and cefalexin

60
Q

what is the spectrum for the 1st generation cephalosporins

A

MSSA and strep. some GNR, klebsiella, proteus.

61
Q

what is cefazolin used for

A

surgical prophylaxis 24hr. (add metrinidazole for colon), MSSA bacteremia, endocarditis, skin and soft tissue. these are suitable for streamlining treatment: broad-spectrum

62
Q

are the 1st generation cephalosporins better tolerated than the antistaphs?

A

yes.

63
Q

2nd generation cephalosporins agents

A

these are the true cephs and cephamycins

64
Q

true cephs

A

cefuroxime, cefaclor, loracarbef, cefprozil

65
Q

cephamycins

A

cefoxitin and cefotetan

66
Q

what is the spectrum for the true cephs

A

gram (+) (strep pneumoniae), gram (-) (H. flu, gonorrhea, catarhalis, some enterobacteraciae).

67
Q

spectrum for the cephamycins

A

less active against gram (+) than 1st gen. gram (-) (more active against klebsiella and e coli, but less active against H. flu. than the 1st gen).

68
Q

what are the true cephs used for clinically

A

community acquired respiratory infections

69
Q

what are the cephamycins used for clinically

A

intraabdominal infections, pelvic and gynecological infections, mixed aerobic/anaerobic infections and surgical prophylaxis.

70
Q

3rd generation cephs

A

cefotaxime, ceftriaxone, ceftazidime, cefdinir, cefpodoxime, ceftibutin, cefixime

71
Q

what is the spectrum of the 3rd generation cephs

A

pseudomonas aeruginosa (ceftazidime), streptococci, MSSA.

72
Q

what do the 3rd gens have NO activity against

A

MRSA, enterococcus, stenotrophamonas, listeria. b. fraglais

73
Q

what do the 3rd gens have limited activity

A

anaerobes

74
Q

what is ceftriaxone used for clinically

A

CA pneumonia, complicated UTI, CA meningitis, CSF Lyme, strep endocarditis, gonococcal and PID, intraabdominal infection with metronidazole

75
Q

what is cefotaxime used for

A

similar to ceftriaxone. preferred in neonates.

76
Q

what is ceftazidime used for

A

pseudomonal infections post-neurosurgical meningitis,

77
Q

what is ceftazidime a poor choice for

A

CA meningitis

78
Q

what are the adverse effects for the 3rd gener

A

correlation with c diff.

ceftriaxone causes biliary sludging

79
Q

which 3rd gens cross the BBB

A

ceftriaxone, cefotaxime, ceftazidime

80
Q

which 3rd gener can be problematic in neonates and why

A

ceftriaxone because of biliary sludging. also interacts with calcium containing medications to form crystals.

81
Q

what is special about the 4th gener

A

they are zwitterion so the neutral charge passes the gram(-) barrier. they also have relative resistance to ampC beta-lactamases.

82
Q

what is the spectrum of the 4th gens.

A

gram (-) excellent activity against enterobacter and pseudomonas. gram (+) high afinity for PBP of +’s MSSA and strep pneumoniae,

83
Q

what do the 4th gens not have activity against

A

MRSA, fragalis, listeria.

84
Q

what are the clinical uses of the 4th gens

A

neutropenic fever, meningitis, ceftazidime resistant enterobacter, similar to the 3rd gens.

85
Q

what are the 5th gen agentds

A

ceftaroline and ceftobiprole.

86
Q

what is unique about the 5th gens

A

they have a side chain that mimics part of the cell wall and acts as a trojan horse.

87
Q

what is the spectrum for the 5th gens

A

gram (+): MRSA, MSSA, strep, faecalis. gram (-): H flu, catarrhalis, enterobacter.

88
Q

what are the 5th gens NOT active against

A

poor anaerobes, and no pseudomonas.

89
Q

what are the clinical uses of the 5th gen

A

complicated skin and soft tissue. off label

90
Q

how can staph become resistant to 5th gens

A

alterations of the ceftaroline binding pocket.

91
Q

monobactam agents

A

aztreonam

92
Q

spectrum for aztreonam

A

only gram (-) enterobacter and pseudomonas

93
Q

what is aztreolam ineffective at treating?

A

gram (+)’s and anaerobes.

94
Q

what is the clinical use for azteonam

A

almsot never used as a monotherapy unless the infection is known to be gram (-). pneumonia, UTI, surgical wounds (gram (-)). used in patients requiring gram (-) activity with penicillin allergy and unable to use aminoglycosides

95
Q

what are the carbapenem agents

A

imipenem/cilastatin, meropenem, ertapenem, doripenem.

96
Q

what is the spectrum for the carbapenems

A

broad spectrum against (+), (-), and anaerobes, some types of MDR gram (-) rods,

97
Q

what are the carbapenems not useful for

A

MRSA, stenotrophomonas, not ideal for enterococcus, or coagulase negative staph.

98
Q

what can we not use ertapenem for

A

pseudomonas, acinetobacter

99
Q

what do we use ertapenem for

A

CA intraabdominal infection.

100
Q

what do we use meropenem for

A

hospital acquired infection, intraabdominal, HAP, VAP, post-neurosug meningitis, ESBL-producing GNR.

101
Q

what do we use imipenem for

A

similar to meropenem

102
Q

what do we use doripenem for

A

same as meropenem.

103
Q

what are the adverse effects of the carbapenems

A

similar to the other betas

104
Q

what is unique about the SE of imipenem

A

it causes more seizures than the others. watch out for the renal failure patient.

pharmacology unit 6 (45 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions